Experimental Muscle

Experimental Muscle

"...8, 9, 10!" gasped Mike, savouring the sensation of the pump in his arms. His last set finished, he put away the weights and flexed his biceps to check his progress.

"Yeah, twenty inches, finally!" Not for the first time he longed for some way to accelerate his growth to absolutely inhuman dimensions.

"Excuse me," said a large young man wearing a lab coat. "But I couldn't help overhearing you. You may be the man I've been looking for. I'm Dr. Logan Green."

"I'm Mike. What do you mean I may be the man you're looking for?" Mike looked at the dark haired man who looked as if he spent all his time in the gym rather than in a lab. He must have outweighed Mike by at least 40 pounds and all of it muscle. What a hot looking man, Mike thought. Mike didn't think there was anyone at the school that big, and being the muscle junky he was, he had made of point of meeting all of the big men on campus. Mike wanted to get to know this man regardless of what he was selling.

"Well, I can see that you've worked really hard to gain the size you have and from what I overheard you, wouldn't object to getting bigger--A lot bigger."

"Hell, I wouldn't be working out so hard if I didn't want to get huge," Mike replied, wondering if this man really had what he had been looking for, other than an incredibly hot body.

"I've been looking for a subject for a muscle growth experiment and it's been tough finding volunteers. No one seems to want to double their muscle mass. And that's what my experiments have produced so far." Dr. Green looked Mike straight in the eye, "I think you're up for it."

"Man, I'd do anything to get that big. Fucking anything." Mike said, almost unable to believe his ears, his greatest wish about to come true. Hell, he'd do a lot for this huge man even without the promise of outrageous growth.

"I won't ask you to do anything you wouldn't want to do," Logan said and flexed his pecs and shoulders. Even the baggy lab coat couldn't hide Logan's massive development. Mike couldn't take his eyes off the huge doctor.

"When can we start?" Mike asked, practically trembling with excitement, wanting to begin as soon as possible. In fact, he wanted to begin right now.

"I'm all set up in the lab to start whenever you like. You look as excited as I feel about my work." Dr. Green smiled knowingly.

Mike grinned back. "Damn right. Let's go."

It was a short walk across campus from the gym to the lab where Logan Green worked. Mike hadn't even wanted to take the time to shower after his workout in his eagerness to get started with the experiment. The lab was more than he expected. Along with the usual technical equipment and computers, there was a very well equipped, very heavy-duty gym. As Mike was looking around, Logan locked the doors then went to a computer console and began typing.

"I'm going to need a blood sample and a muscle biopsy in order to produce the growth factor. It will be have to be tailored to your own cellular structure and biochemical pathways." Logan then explained that one of the limitations to the growth would be the protein and energy resources of the subject's body. Once those were used up, they have to be replaced for the growth to continue. "Fortunately, I've been able to formulate a protein fuel that the growth factor can metabolize almost immediately. The rate of growth is essentially limited only to how fast you can drink the protein."

The blood sample and biopsy took just a few moments to perform. Mike's body fat was already pretty low so that the needle didn't have to penetrate as far or as painfully to get the muscle sample as it would with someone else. The doctor injected the specimens into the largest machine in the lab and initiated his programs.

"I'm going to have to ask you to strip down to your jock. I need to take some measurements before your injection if I'm going to get accurate data for the experiment. Don't worry, this won't hurt a bit." Logan smiled, "and no one is going to walk in on us."

Mike didn't need to be asked twice. He was proud of his body and would have willingly stripped bare and more to get on with the experiment. "I've tested the procedure on myself, and even taking the smallest amount of growth factor I could measure, I was able to gain over 100 pounds of muscle." Logan took off his lab coat and rolled up his sleeves revealing his incredibly thick and vascular forearms. The doctor was huge and looked as if he could win any bodybuilding contest he wanted. Even Mr. Olympia didn't have this guy's proportions. Mike could barely control himself as he considered Logan's massive physique and what the growth factor would do to him.

Mike had never been so thoroughly measured in so many ways before. Each of his muscles was thoroughly quantified in size, shape, mass and density. Logan was full of praise and encouragement, clearly enjoying himself as he asked Mike to flex each of his muscles. When he was done, Logan read out the results of the measurements. Mike was a massive 240 pounds at 6 feet tall. His arms were actually just over 20 inches and he had a 50 inch chest, 33 inch waist and 30 inch thighs. But even Mike's huge dimensions were no match for Logan's. Having this hot, muscular man touch and praise his body was incredibly sexy. Mike's dick began pushing against the thin fabric of his jock strap.

Logan couldn't help but notice Mike's growing arousal. "Come with me and let me show you something." He walked over to a computer console and typed out some commands and a video monitor lit up. "This is me last week before I tested the growth factor."

"That's you?" said Mike, incredulously. It had taken him a moment to recognize that the naked man on the screen was indeed Logan. Even before the growth, Logan was a hot looking man with a good build and a hefty looking dick. "That's incredible. You weren't kidding about about this, were you?"

"Not at all," Logan said. He hit a few more keys and a series of images flashed across the screen. "I've had to edit the images quite a bit. Some of my reactions to the process were rather x-rated." Logan looked over his massive shoulder at Mike's nearly naked body. "I think you know what I mean."

Mike's jaw dropped and his dick popped out of his jock as he watched Logan literally growing before his eyes. It looked like a cartoon, the growth was so outrageous. There were nine shots of Logan and each image was accompanied by a set of numbers describing his expanding physique. Mike watched Logan's weight surge from 180 to 270 pounds while his bodyfat fell to practically zero. His arms grew from 17 to 24 inches and his chest from 44 inches to an awesome 60. His quads had grown from 25 to 40 thick and cut inches and his muscular calves now flared at 23 inches. Only his waist stayed the same at 30 inches with mind boggling lats forcing his arms from his side. To Mike's disappointment, Logan's crotch was fuzzed out in all but the first picture. Even with his clothes on, Mike could see that the doctor was even bigger now.

Logan turned around revealing a massive hard-on running along his big thigh. It looked as if the growth factor worked on more than just muscle. He wrapped his hand around Mike's hard dick and said, "I get hard just thinking about the process. Hot, eh?" Mike nodded. "You still haven't seen the latest results of my growth," Logan said and began to unbutton his shirt.

Mike's dick throbbed as the massive column of Logan's neck and the slabs of hairless pectoral muscle were revealed. When Mike pulled Logan's shirttails from his pants, Logan stopped undressing to let Mike take over.

Mike finished unbuttoning Logan's shirt and let it hang open, marvelling at the densely muscled six pack bulging above Logan's belt, the deep cuts between the rock hard abs were remarkable, not even when Logan took a deep breath was the definition obscured.

"Go on," said Logan. "It'll be a while yet until your injection is ready. I'm sure you can think of some ways to pass the time." He winked and flexed. "I know I can."

Mike needed no more encouragement. He wanted Logan's dick and he wanted it now. He undid Logan's belt and pushed down his pants, struggling to get them past Logan's gigantic thighs. Mike knelt down and looked up in awe at the massive man standing with his shirt open, pants around his ankles and tight white briefs that barely contained his hard dick. Mike ran his tongue along Logan's cloth covered dick, soaking the underwear. Logan groaned as he felt Mike's hot breath on his dick and pushed his crotch into Mike face, nearly knocking Mike over with the force of the passion flowing from his muscular quads. Mike grabbed hold of Logan's rock hard ass bringing his own not inconsiderable strength to bear to keep his balance and his mouth on Logan's dick.

Logan grabbed Mike's thick deltoids and rubbed his massive jockey-covered dick across Mike's face, moans of pleasure escaping from his lips. Frustrated with the fabric between him and Logan's dick, Mike took hold of the waist-band and pulled it apart, tearing the cloth away from Logan's muscle-packed groin, the effort hardening his shoulders under Logan hands. Again Mike paused, he had never seen a sexier sight. Logan's clothes in disarray enticingly hid much of his massive physique sending shivers of anticipation down Mike's spine. He took Logan's balls into his mouth and teased the head of Logan's thick 9 inch dick. His entire field of vision was filled with Logan's rippling body, his ministrations causing the bodybuilding doctor to gasp.

"Oh yeah, man," Logan groaned, digging his fingers into Mike's delts, "suck my dick!"

Mike obliged with enthusiasm, excited by his power over the huge man and deepthroated Logan's cock. He ran his hands over Mike's massive chest and chisled abs, blown away by the sheer density of the muscles. Grasping the base of Logan's dick, Mike applied powerful suction to the mushroom head causing it to expand even bigger. With a grunt, Logan clenched his abs into six massive bricks and Mike slowly traced out each incredible contour and sucked Logan's dick even harder.

Then Mike turned his attention to Logan's insanely thick quads and calves. Logan flexed his legs for Mike, bending his knees to bring out the definition of his hamstrings. Leaving off Logan's dick, Mike began running his tongue over Logan's left thigh, pressing it into the deep cuts then over the striated muscle. His fingers traced out the separation of Logan's diamond-etched calf, each hand cupping the twin heads of flaring muscle while his mouth travelled over the huge tear-drop shaped muscle bulging over Logan's knee. Then he traced the solid cord running along the inside of Logan's thigh into his groin, biting and sucking Logan's ripped muscles. Logan relaxed his quads and still the muscle barely yielded to Mike's probing tongue. Taking hold of Logan's thigh with both hands, Mike shook it back and forth the way he had seen the pro's do on stage, amazed at just how heavy the muscles were. "Flex," he whispered and Logan tensed his thigh hard with a groan. Hard veins appeared under the thin skin which Mike followed with his tongue up and down the entire length of Logan's leg.

Logan lifted Mike to his feet and pulled him into a powerful bear hug, crushing the taller man's body into his much more massive frame and kissing him passionately. He cupped Mike's ass in his hands then began massaging it hard, pulling Mike's groin into his. Then, effortlessly, Logan snapped Mike's jock into pieces, freeing Mike's dick. Without warning, he swept Mike off his feet and cradled him in his arms, his shoulders and arms stretching the fabric of his shirt, looking as if he were about burst out of it.

"Holy--!" Mike's exclaimation became a moan of pleasure as Logan curled his 240 pound body as if it were a barbell, lifting Mike's cock to his mouth. Logan hefted Mike up and down, pushing Mike's dick into his mouth and then letting it slide out as he lowered his friend's body. Mike grasped Logan's arm to feel the strength and size of the muscles powering this amazing blow job. The effort of curling his massive buddy sent a rush of blood into Logan's huge biceps, pumping them up even bigger. The sensation of huge, hard muscle flexing sent Mike flying. Unable to contain the 24 inch biceps, Logan's sleeves burst at the seams. Mike tore away the cloth and began licking the hot bicep as it lengthened then contraced to a phenominal peak as big as a softball. Grunts and moans erupted from Logan, sending even more incredible sensations down Mike's dick. Logan pumped out a few more reps bringing Mike to the edge of cumming, then set him back on his feet.

"Wow," said Mike, trying to catch his breath.

Logan pulled away the shreds of his shirt and kicked off his pants and shoes and hit an incredible double biceps pose. Then he straightened his arms out, flexing and twisting them from the shoulder displaying the corded muscles, his huge triceps hanging like horseshoes big enough for an overgrown Clydesdale. He flexed his pumped biceps again hard, making veins pop out all over his arms. "Boom!" He laughed. "Just think, pretty soon you're going to be even bigger than this," he said. Mike grabbed Logan's elbow and ran his tongue all over the flexed biceps and triceps, tracing the blood engorged veins and the textures of the striated muscle. Logan hit a Frank Zane pose with his elbows over his head and hands clasped behind his neck. Mike attacked Logan's armpits, biting the hot flesh, inhaling the musky scent, the taste of Logan's sweat as powerful an aphrodisiac as his muscles. Then he moved to Logan's bulging trapezius and neck, covering them in spit, his kissing and sucking rewarded with moans.

Logan pulled Mike's face to his in another passionate kiss, his tongue parting Mike's lips. Mike ran his hands over the expanse of Logan's chest, then traced the ridges of his abs, the slabs of muscle expanding and contracting with Logan's heavy breathing. Mike pulled Logan's dick between his big thighs and let his own rub against Logan's six-pack, sliding it up and down the deep cut between the abs. Logan pumped his dick between Mike's sweat slicked quads, then briefly broke off the kiss to say, "Flex your arms for me, Mike." Logan grasped Mike's 20 inch arms and increased his fucking motion, groaning, "Big arms, gonna make them even bigger."

"Oh, man!" said Mike, flexing his biceps as hard as he could. He couldn't believe the huge doctor was getting off on his muscles! He extended his arms to his sides like Logan had done for him, Logan's hands stroking and squeezing Mike's huge arms. The two men continued to push against one another, rhythmic thrusts of hard cock against harder muscle coming faster and faster. Torrents of sweat poured from their bodies, lubricating their action.

Mike abandoned his posing and threw his arms around Logan, lifting the 280 pound man so that Logan's chest was within reach of his questing tongue. Mike buried his face between Logan's pecs then ran his tongue from one side of the broad chest to the other, biting and sucking each erect nipple and the muscle in between. As he ran his tongue along the huge cleft between the pectorals, Logan flexed, deeping the cut between heavy slabs of beef.

Mike let Logan down and said, "I love your pecs, guy."

"They're all yours, Mike," Logan replied. A glint appeared in his eyes and he dropped to the floor and did a couple push-ups, his form flawless, his back flexing hugely. For the first time, Mike got a good look at Mike's broad back. Flex Wheeler had nothing on Logan! Mike still couldn't believe the narrowness of Logan's waist, the thickness and width of his lats, the way his traps bulged into mountains with each push up. Mike's hand wandered from the christmas tree striations of Logan's lower back onto his equally striated, perfectly shaped ass.

"Get on my back," said Logan.

Laying his dick between Logan's muscular bubble butt cheeks, Mike set his 240 pound frame on top of his gigantic friend. He pressed his chest into Logan's expansive back and stretched out. A sound halfway between a grunt and a moan rumbled in Logan's chest as he pressed up their combined weight, well over a quarter ton of muscle! Mike first grasped Logan's triceps, feeling them quiver and flex with the effort of the push up. Reaching around Logan's flaring lats, he took great handsful of the flexing mounds of pectorals, the skin drawning taut as Logan's pecs stretched at the bottom of the rep. Mike's knuckles grazed the floor and he tightened his grip as Logan pushed up, feeling the massive pecs flex bigger and bigger, threatening to burst the thin layer of skin. Mike ground his dick along Logan's ass and writhed against the flexing mountain of muscle below him.

"Work those pecs, man!" said Mike. "Huge fucking pecs!"

Logan powered out a few more reps, overwhelmed with excitement at his new strength and Mike's hard body and dick pressing into his back. Mike's enthusiasm and unabashed worship of his muscles was about to send him over the edge. He forced out one more rep then let himself fall to the floor. They lay still for several moments, both knowing that almost any motion would bring them off.

Mike sat up and straddled Logan's waist, his dick fitting snugly into the deep crevass between the heavy ridges of muscle running along Logan's spine, and started massaging Logan's oversized traps and delts. He kneaded the huge lats that spread from Logan's wide shoulders to his narrow waist, then brought all his strength to bear on Logan's incredible traps.

Suddenly, Logan twisted between Mike's legs, sat up and pushed Mike onto his back, pinning his arms to the floor. Logan shifted his grip so that he kept both of Mike's wrists in one hand and slid down Mike's to attack Mike's sweaty arm pit. Logan nuzzled the sensitive flesh making Mike writhe with pleasure. When Mike's hips began bucking, Logan released his grip on Mike's wrists, sliding further down to take Mike's dick into his mouth.

Mike threw his legs over Logan's shoulders and lifted his hips to meet Logan's powerful suction. Logan placed a hand on the small of Mike's back lifting his ass higher, his thumb searching out and stroking Mike's asshole. Logan locked eyes with Mike, his hand replacing his mouth on Mike's dick. He let a drop of spit fall to Mike's ass and worked his thumb into Mike's hot ass. Mike clenched his ass around Logan's thumb, moaning and forcing his hips into Logan's probing hand. Continuing to stroke Mike's dick, Logan said, "You want this muscle man to fuck you? You want 300 pounds of muscle fucking your ass?"

"Yeah, Logan, I can't take any more. Fuck me! Fuck me hard!"

With that, Logan reached his arms under Mike's back and lifted him onto the desk. He opened a drawer and pulled out some lube and poured some onto Mike's hot ass and slowly pushed one finger then two into Mike's twitching hole. Pressing their dicks together with one hand, Logan jerked them, getting them slick with lube. Mike's dick was so hard it slipped out of Logan's grip, hitting his abs with a meaty thunk.

Logan picked up a container of muscle growth fuel from the counter beside his desk and threw back what must have been a gallon. He tossed the container away, and drank down another. Then another. His skin became flushed and the veins on his body pulsed with supercharged blood. He pulled Mike's legs around his waist and aimed his dick at Mike's waiting hole.

"Man! Fuck me now!" Mike cried.

Barely under control, Logan rammed his dick into Mike's tight ass, waves of strength surging thoughout his body. Mike's muscular ass gripped Logan's dick like a vice. Logan leaned over and grabbed the sides of the desk, slamming his dick into Mike's willing hole. Mike took Logan's upper arms into a tight grip, feeling the already huge muscles beginning to grow even bigger.

"Muscle, muscle, muscle," breathed Mike, his lust for Logan expanding with the doctor's growing body, inspiring an equal arousal in Logan. Logan threw his head back and let out a deafening, primeval roar, searing Mike's gut with hot cum, unable to hold back so erotic was the sensation of giving pleasure and the awesome sensation of his muscles growing larger, filling with more and more incredible mass. If anything, Logan's dick became even harder as he continued to grow and fuck his muscle buddy. Mike could barely believe his eyes. It was like being fucked by the Incredible Hulk! Logan reared back, never missing a stroke of his fucking, and hit a massive double biceps, his arms now pumped up to 25 inches and still expanding with hot, hard muscle.

"Holy shit!" yelled Mike, reaching for Logan's growing cannon- ball biceps. He cupped the surging muscles, feeling them grow and expand bigger and bigger, pushing against his hands. It was the ultimate posing display! The sensation was too much, much too much! His dick, untouched, let fly, spurt after spurt of his cum covering his face and chest.

Logan's assault on Mike's ass continued relentlessly, powered by increasingly larger and larger quads that bulged obscenely against the desk, each individual massive muscle cording his thighs standing out and growing, looking like the root system of a sequoia. Mike moaned out encouragement, his legs around Logan's waist pulling the growing giant deeper into his ass. His dick was still rock hard and he felt like he could come again and again, he was so turned on by the Logan's muscles and cock. Logan dropped his arms and hit a lat spread, the muscles growing heavier and heavier. Mike had to stretch to reach the expanding muscles as they grew wider and wider, the slabs of awesome muscle vibrating with power and mass.

Logan hit pose after mind-numbingly massive pose. He was now well over 320 pounds of freaky muscle. His shoulders had grown and grown, each as big and as hard as a bowling ball. His pecs were twin plates of eye-popping, shredded muscle, huge square mountainous slabs pushing and growing outwards. Veins like ropes covered the muscle stallion's massive frame and even when Logan relaxed between poses, his muscles stood out as rawly defined as the anatomy chart of a demi-god.

Abandoning his posing display, Logan pulled Mike to his heaving chest and easily lifted him from the desk. Mike threw his arms around Logan's unbelievably wide shoulders, stunned at the way Logan's muscles continued to grow and pulse against his body. Logan carried him across the room, Mike's ass still impaled by Logan's throbbing dick. Logan stopped with his back to a mirror and stood with his tree trunk legs planted far apart and knees bent supporting Mike with his now 45 inch quads. Mike looked over Logan's enormous trapezius into the mirror at the vast rocky terrain of Logan's back flaring from his tiny waist to his ever widening shoulders. Mike was overwhelmed with the sheer width and thickness of Logan's back. Relaxed, the muscle hung like two sides of beef beside his spine. Flexed, his back was a gut wrenching, pulsing mass of incredible contours, muscles crowding and pushing each other into fantastic prominence. Even the globes of Logan's muscular ass were thicker and ripped to the bone.

Gripping his lats securely just under his arms, Logan bounced Mike up and down on his dick, rippling the giant muscles of his arms and shoulders. Mike's dick slid up and down the huge cubes Logan's washboard stomach, butting up against the huge protruding shelf of pectorals which Logan flexed, squeezing Mike's dick between the slabs of beef and sending Mike into paroxysms of pleasure. Logan's bouncing became more frantic and powerful and he stood on his toes and flexed the now absolutely freaky 30 inch calves that swelled from his legs, the hugely gnarled muscles easily lifting both men.

The masses of ripped muscle pulsing against his skin, the sight of it flexing and rippling under paper thin skin, the sheer unreal size of the muscle man fucking him was about to send Mike over the top again, his dick was so hard he thought it would explode. "Oh man, I'm going to cum!" moaned Mike. "Flex your arm for me, muscle stud!" Mike threw one arm around Logan's muscle corded neck as the muscle man raised his mighty arm and flexed the absolutely huge, incredibly peaked, savagely dense 28 inch biceps. As soon as Mike's tongue touched the insanely huge muscle, cum exploded from his dick in a mind shattering orgasm to plaster Logan's pecs with an endless stream of white spunk. Roaring inarticulately, hips spasming, Logan let loose with one final, earth shaking thrust, ramming his dick deep into Mike's ass and shooting spurt after spurt of hot cum into Mike's gut, every muscle on his body flexing hugely.

They held still, every tiny movement taxing their overextended senses. After a while, Logan gently lifted Mike from his dick and stepped back against the mirror and slowly slid to the floor. Both men lay spent and shaking with the power of their orgasms and the power of this unprecented fuck. With bodies plastered together with the stuff of two of Mike's orgasms, they shared a tender kiss. As their breathing slowed and quieted, they heard a beeping coming from growth factor machine.

"It's your turn, Mike," said Logan.

Experimental Muscle, Part 2

Logan pulled Mike up onto his feet and led him to the side of the muscle growth factor machine. Three large beakers were filled with liquid. Mike was eager to drink it down, having seen the amazing muscle growth of Logan before his very eyes. He had always dreamed of being that big and now here was his chance.

"Because you were working out just a while ago, your muscles should be primed for rapid growth," Logan told him. "If you're willing, start with one of the beakers."

Mike picked it up and drank it down. It had a slightly salty taste and was a

little thicker in consistency than milk. Then he realized it was a lot like cum! He finished the liquid and put it back under the spigot. Mike looked at Logan expectantly, then down at his own already big frame. Several minutes passed and nothing seemed to happened. Disappointed, Mike grabbed the second beaker as the first was refilling, and quickly gulped it down. He reached for the third and Logan said, "Wait Mike, not so fast." But Mike had seen the effects that the growth factor had had on Logan and he was desperate to match him - even to surpass his fantastic development. He ignored the scientist and poured the contents of the third beaker down his throat.

Slowly Mike noticed a warm feeling beginning in his stomach. "I think it's starting to do something," he told his buddy.

"If you start working out, it will work more quickly," Logan told him.

"Here, let me get you a jock and a pair of shorts. Though it seems a shame to cover up even a small part of you."

Logan handed Mike some clothes, then put on a pair of sweatpants and tank top that stretched so tightly over his now enormous torso that the material became thin. Mike stepped into the workout gear and headed to the weight area that had been set up on the other side of the lab. He felt the warm feeling coursing throughout his body now, spreading out down his legs and out along his arms. It felt good. He loaded some large plates onto the bar at a benchpress station and laid down on the bench. Logan came around to spot him, and Mike looked up at the meat-packed basket hanging over his face.

Logan was an incredible sight of hard muscled splendor, and all Mike wanted was to grow, so that his mentor would be proud of him. Mike pushed up on the bar and started benching. The heat in his body was intense now, and it felt great, like having a super-pump. By the end of the set, Mike noticed that the weights felt much lighter than when he had started. He looked down and saw that his pecs had grown a half an inch or more. It was as if the growth factor was accelerating the effects of the exercise, so it was as if he had done a hundred sets or so at that weight. Logan noticed and said, "Yeah, you're on the way to being a really big man." He added another plate on either side and waited for Mike to start again. They continued like this for several more sets, Mike's chest and arms swelling larger and larger.

"Time to work out some other body part," Logan said. "How about building a really broad back?" he said with a smile. Mike rushed over to a T-Bar and started rowing it up and down. He was getting off on this. Logan was too - it was hot to see this eager musclestud trying to get more massive. Mike sat down at a bench and grabbed a hundred pound dumbbell in each hand. He brought them up and started cranking out rep after rep of shoulder presses.

He threw them down and reached for 120, then 140, and only stopped when the 180 pound dumbbells seemed too light to be worthwhile.

Just then the muscle growth machine started beeping again. The three beakers had filled up again. Mike leapt up and ran over to the machine. He grabbed the first and drank it down. Then he picked up the second and drained it as well. As he picked up the third Logan again warned him about not going too fast. But Mike was too excited to stop. When he had wiped his mouth off he turned to Logan and said, "How am I doing so far?" Logan got a tape measure and Mike flexed his huge chest. The nipples stretched out the tape at 60 inches. Mike raised up his right arm and made the biceps bunch up in a display of vein-encrusted power that got Logan excited. "Those guns are already at 24 inches, and you still haven't worked them out yet," Logan said in shock.

Mike went back to the gym and started putting the plates on the leg press machine. He got down in position and started pushing the platform up and down, up and down. He had Logan busy adding more weight until there were 10 45-pound plates on each side and several on the top spindle. "It's not enough," he cried. "Jump on!" Logan climbed up onto the bar, his 320 pound frame adding to the weight. He was fascinated as Mike pushed him and the weights up and down, over 1500 pounds in all! The huge thighs worked like pistons forcing the weights and the muscular scientist up, then down, over and over. Mike shifted his footing so that he was able to start working his calves, which were ballooning before their eyes. "It's still not enough!" he screamed and started pressing the full weight up again, this time using only one leg at a time. Logan couldn't believe it. He had never dreamed that his formula could have had such an effect.

Once again the machine began beeping. Mike rushed over to it, and Logan came up behind him. He grabbed the huge man's arm and said, "No Mike, it's too much." Mike pulled away and roared, "More muscle!" He held the scientist back with one freakishly huge arm as he reached for a beaker and drank it down. He polished off the others and turned to Logan with an evil smile on his face. Logan stepped back, a little afraid of this giant man. Just then the machine started making a strange noise and smoke drifted out of an instrument panel. Logan rushed over and flipped some switches. "It's burnt out. You've drunk so much growth factor that it couldn't keep up with you."

"Then let me get the most out of what I've just had," Mike replied. "I want to get bigger and stronger. I want you to be proud of this huge body that you helped me make." He put his massive arms around his mentor and held him tightly, staring him in the eye.

"Mike - you're getting taller too," Logan said with surprise. "It must be your body's way of keeping up with the fast pace of muscle development." Mike was now quite taller than Logan, even as his muscles began to fill in even more.

Mike went once more to the gym area and picked up the bar from the benchpress station. He began to do barbell curls, with 500 pounds on the bar. Logan looked on in rapt attention as the huge biceps bunched up, then relaxed.

Mike took the 180 pound dumbbell and pushed it up overhead, working his enormous triceps. Logan watched them get bigger with every rep. The growth factor was multiplying every rep thousands fold, allowing the muscle to grow ever larger. Mike had close to 750 pounds on the barbell now, and he picked it up with one hand and started curling it. He switched from hand to hand, heaving the weight up and down, the plates clanking together. It seemed effortless. He caught Logan watching him, his mouth gaping open in amazement, and he smiled. He put the weight down, walked over, and wrapped his arms around the awestruck man. "Thanks Logan. I owe this to you. Let's see how we did."

Mike got on the scale, and the needle spun around past 500 pounds. He now towered over Logan, who measured him as being 7'1". Logan wet his lips and said, "Let me measure your huge muscles, Mike." The supernatural man obliged, flexing the almost-grotesquely huge right arm. "Mike, these are 36 inches around," Logan cried. "And they are so dense, vascular, and striated.

The knot of muscle on the peak is almost as big as your arms were before you started, and they were 20 inches then." Mike drew in a breath and puffed up his chest. The pecs were like two mountains, crisscrossed with veins and the striations of the muscles showing through the razor thin skin. "Mike, the tape stops at 70 inches. Your chest must be at least 80 inches around!"

The well-defined waist, carved out of muscle, was 38 inches around. Mike's thighs were 54 inches, and his diamond shaped calves were an astounding 36 inches of rock hewn muscle. Logan had knelt down to measure the calves, and now he looked up at the god of muscle who stood above him, looking down with a smile. The shorts that Mike were wearing were tight, digging in around his legs. The huge bulge of the basket reminded Logan that everything about Mike had grown. He reached up and slowly brought the shorts down. The jockstrap was filled with meat. Logan pulled that off too, releasing the heavy balls that drooped down, big and heavy as grapefruits. Mike's cock flopped out of the jock. It was much thicker than before, and longer. Mike seemed to read his thoughts and said, "Guess it needs a workout too."

Mike stepped back and stroked the big dick a few times. "I sure got horny doing all of that lifting," Mike said. The monster cock was now stiff, and Logan got the tape measure once again. "It's 13 inches," Logan whispered.

Mike abruptly turned and went over to the weight area. He pulled three 45 pound plates off the rack with one hand and slid them one after another onto his fully engorged dick. The shaft was so thick that he couldn't have pushed the plates all the way to the bush of pubic hair that surrounded the huge organ. He started throbbing it so that it lifted the plates up and down.

Logan stared rapt as the plates rattled together as Mike throbbed his huge tool. Then Mike threw the weights to the floor and said, "Enough tricks.

How would you like a good look at this muscle?" With that he shot a double biceps pose, bringing his huge arms up. The enormous muscles sprang to life and Logan gave out a low moan. The heads of Mike's deltoids stood out starkly as he flexed and posed for the appreciative man. He turned and spread his back out, the lats winging out from his sides. Turning his side, Mike forced his pecs to jut out in a display of brutal mass. He put one leg out in front of him and tightened the upper leg. The muscles of his quads jumped into relief, all of the veins and striations looking as if they had been etched into the thick muscles. Then he squeezed his arms together in a most muscular pose. Every sinew popped out, incredible mass on display for Logan's pleasure.

"Mike, I never dreamed that the growth factor could be so successful. But it was your hard work building your body before now that really enabled you to have such fantastic results. I'm proud of what you've done," Logan said.

Mike smiled, walked up to him, and picked him up in his mighty arms.

"Thanks, Logan. I wanted you to be proud of me. Now let's see if I can thank you enough."

Mike put Logan down and once again flexed his right arm bringing the astounding biceps down to Logan's eye level. He straightened and flexed the arm over and over as Logan lipped his lips. Finally the scientist grabbed the biceps in his hands, eagerly feeling the hardness of the muscle as it peaked and relaxed. Mike lifted his arm a little and Logan held on, basically doing chinups on Mike's enormous arm. He slipped back down onto his feet and said, "I thought I was huge, but you are inhumanly huge! I almost feel small."

"Are you kidding?" Mike replied. "You make Dorian Yates look like an anorexic. You are one hot sexy dude! Flex for me."

Logan obliged by puffing his barrel chest up, the nipples pointing almost straight down because the muscles were so huge. He did a side triceps pose as Mike looked on appreciatively. Then he stopped and said, "Mike, you are the biggest man to ever walk the planet. Show me more if you want to find a way to thank me for helping you."

That's what Mike had in mind. He loved the freakish size that he had attained, and he wanted to show it off. Who better to flex for than the man who had helped him get so gigantic? He went through all the posing moves he had ever seen the pros do. When he flexed his back, every muscle popped out in relief, a display of brutal power. Standing on his toes, his calves exploded into diamonds of vascular muscle. He swung one arm up and flexed while showing his monstrous chest in a side pose. Logan's big cock was getting hard as he witnessed this posing routine of a lifetime. "Mike, I can't hold off any more. Let me feel your rugged hard body, " he said.

"With pleasure," Mike said with a grin. Logan stepped up to him and started running his hands all over Mike's body. "So hard, so unbelievably hard," Logan said softly.

"What was that? I can't hear you," Mike said.

"You're so fucking hard Mike! Your muscles are incredible," Logan repeated loudly.

"Yeah, two hard musclemen flexing for each other. Nothing is hotter than that!" Mike roared.

They continued feeling each others massive bodies, their cocks banging against each other. Mike brought his head down so that they were able to kiss, their tongues swirling around each other, probing and flicking around each others mouths. Mike picked Logan up and walked over to where the scientist had left the lubricant from before. He gently put the big man down on the desk, then squirted some lube into the baseball mitt-sized right hand.

Logan gazed at him, a look of eager anticipation on his face. He knew what was coming, and he wanted it badly.

"You fucked me like I was never fucked before," Mike said with a smile.

"Let's see if I can repay you." With that he put his monster cock head against Logan's butthole. He grabbed Logan's thick, hard thighs and put them over his barndoor-wide shoulders. Slowly he started to push his rod into the prone stud. Logan took a deep breath as Mike's thick pole stretched his asshole to what seemed the limit. Mike sensed that he was going a bit too fast and eased up a little. The two musclemen stared into each others eyes as Mike slowly fed inch after inch of his horse-sized tool into Logan. Logan felt along the titanic arms that held his shoulders down. The invincible strength of Mike's arms had been apparent in the unnatural workout that Logan had witnessed. Now this superman had him completely in his control, and Logan loved it. Mike started to move his cock in and out of Logan's tight butt. Logan couldn't believe how great it felt. Their gazes were still locked as Mike bent down and kissed Logan. Mike let his cock throb a little in Logan's ass.

"Mike, I'm in heaven," Logan said. "Seeing your huge body over mine, feeling your dick, I love it."

"Almost as much as I love seeing your massive stud body writhing with every thrust," Mike replied. "I love seeing your big muscles tighten."

Mike started to pick up the pace, his hips rocking back and forth as he slammed his cock further up Logan's ass. He put his arms around Logan's big back and backed up so that he was holding the stud scientist up as he fucked him hard.

"Flex for me man," Mike said. Logan's tensed his powerful stomach muscles so that he was able to keep his body somewhat upright while Mike continued fucking him. Logan flexed his gigantic guns, and Mike smiled. "Yeah, big man. Gotta fix that machine so you can get bigger."

"Flex for me now, superman," Logan begged. Mike happily obliged, his arms swollen with disgusting musclemass. Logan grabbed onto the barbaric biceps and helped to force Mike's dick all the way up his ass. Mike bucked his hips as Logan pulled on him with his arms and legs, ramming the thick cock in and out faster and faster. Logan's own sizable rod was rubbing against Mike's granite washboard abdominal muscles, and the friction of that along with the relentless pounding against his prostrate was bringing him to orgasm.

"Mike, I can't hold on much longer," Logan cried. "You're going to make me shoot my load! Flex!"

"Yeah, let me see that cum spraying out of your big cock!" Mike said. Once again he flexed his right arm. Logan watched as the 36 inch arm swelled as Mike flexed his beefy arm. The triceps bellowed out whenever Mike stretched his arm, preparing for the next flex. Logan grabbed hold of Mike's arm and a strangled sound came from his throat. Mike's pelvic thrusts were bashing his dick deep inside of Logan, and it was too much for him. Logan's balls contracted with a tight squeeze, sending a rocket of cum shooting over Mike's shoulder. Again and again the spunk came shooting out of the big stud's cock, spraying against Mike's pecs and stomach. The contractions of Logan's ass sent Mike over the edge too. His bulls-balls sent thick hot cum deep into Logan. The scientist felt every shot of Mike's semen as he continued stuffing his rod up Logan's ass.

Logan was panting as his still-hard cock throbbed against Mike's tight waist.

Mike was smiling, and Logan saw his own jism sliding down Mike's pecs, heading down to the deep crevice that separated the two enormous mounds of muscle. Mike brought Logan's face up to his, his lips pressing against Logan's as he forced his tongue into Logan's mouth. Logan returned the kiss, sighing at how good this had felt.

Eventually Mike slowly pulled Logan off of his cock, the erection beginning to subside. Logan stood on his own two feet, reached his arms around as far as he could around Mike's back, and rested his cheek on one of Mike's hard pecs.

"I have a feeling that this could be the start of a beautiful relationship," Mike said, then laughed as he squeezed Logan tightly.

"Watch it, you'll crush me without even knowing it," Logan said with a laugh. "Let's see if we can find some clothing for you. I guess that the shorts will still fit, and I have some flip-flops that will do for now. I'm not quite sure that the world is ready for someone sized like you, though."

"Well, they'll have to get used to me," Mike said as he squeezed Logan again.

"You seemed to do OK."

Experimental Muscle, Part 3

Logan retrieved the tank top and sweats that he had worn while Mike was experiencing his rapid growth. Mike found the jock and shorts and pulled them on carefully. His thighs were now so large that the material was stretched to the limit. Logan turned around and laughed when he saw Mike.

"I'm sorry, but those shorts look so tiny now, like a bikini swimsuit, that it's almost not worth it."

"And of course none of my old clothes will fit me anymore," Mike said. "I guess I'll have to have all my clothes custom made from now on."

"I have some stuff at my apartment that you might be able to fit into. Let's stop off there, then get something to eat. After all we've done this afternoon, I'm starving," Logan said.

"Me too. And then we have the whole night free to flex and fuck!"

Logan opened the lab door and let Mike precede him. The colossal man had to stoop to keep his head from hitting the doorjamb. Logan locked the door, then sucked in his breath when he turned around and beheld Mike as he walked down the hall. Mike's back was wide as a barn, alive with muscles that rippled as he walked. His arms hung down from his sides like sides of beef hanging in a meat locker. The massive calves and hamstrings jumped as he headed toward the exit. They left the lab building and headed down the street back into "Collegetown," the shopping streets at the edge of the university campus.

It was the beginning of the evening and still very light out. Quite a few people were out walking, and everyone stopped still or turned their heads as the two muscular men stode along. Under any other circumstances Logan's immense physique would have had people staring, but most of the attention was drawn by Mike. Towering just over 7 feet tall, muscles packed over every inch of his body, Mike was a sight that they had never seen before.

"Yeah, they're getting a look at what really big men look like," Mike said to Logan. Both of them were getting off on the stares and cries of the people that they passed. One woman whistled, and at the street corner a guy started licking his lips as he stood next to them, waiting for the light to change. A delivery van went by, and when the driver got a look at Mike he stuck his head out the window and looked back, unable to believe his eyes. A bus reached the intersection at the same time, but the driver saw too late.

He swerved, but crashed into it all the same. Logan and Mike ran over, just as the driver stumbled out.

"Are you OK?" Logan asked. The driver just looked past him at Mike, staring at the gigantic man who was clothed in only the skimpiest outfit. The bus driver got out - luckily the bus had not been severely damaged and the few passengers were unhurt. "Why weren't you looking where you were going you - Jesus!" the bus driver yelled at the van driver, stopping when he saw what the driver was staring at. "Yeah, I'm OK," the guy finally managed to stammer out. Just then, a police car came up the street, siren blaring. Its progress was blocked by the van and bus. The cop came on over the PA system, "Move that van! We've got an emergency up ahead. Another car will come to take care of you."

The van driver looked at his vehicle. The front axle was twisted so that there was no way that he'd be able to move it. The bus was too damaged to move either. By now a string of cars had blocked the police car from behind, and he was stuck.

Mike looked at Logan and said, "I'm partly to blame for this mess. Maybe I can help fix it." He walked over to the van and crouched down a little.

Taking the rear bumper in his hands, he straightened his legs out. The rear of the van rose up, and Mike shifted his handhold to get a better grip. He moved his hands along until the van was level, then he pressed it up over his head. "Oh my God!" the van driver and bus driver cried at the same time. Logan wasn't surprised by this feat, after what he had seen in the lab's gym, but he was still impressed all the same. Here was incredible power on display!

Mike walked between two parked cars onto the sidewalk, all the time the van held high overhead. People pointed and gasped, and one guy hanging out of an upper floor apartment window started filming the scene with a video camera.

Mike carried the van along until he could place it back down in the street, leaving a passage for the police car.

The officers sat stone still in the car, until Logan walked up to them and said, "Hey - snap out of it. Get to your emergency." With that, they blinked hard several times, slowly pulled past Mike, then sped off, only to stop four blocks down the street.

Logan walked up to Logan and slapped him on this broad back. "You are amazing man! There is no one in history who could ever hope to match what you just did! Watching you was such a turn on, let's hurry back to my place where I can worship that strength some more."

Mike grinned. "Yeah, being super strong gets me super horny."

They continued down the street until they came up to the police car. It was parked outside of a clothing store, where a small crowd of people were looking inside. Mike pushed past and into the store, Logan right behind him.

Again the cries and exclamations of the crowd echoed in their ears.

"What's going on?" Mike asked one of the cops who had been in the trapped cruiser.

"There are two students trapped in there," the cop said pointing to the back of the store. "This was an old bank building from the turn of the century.

When it closed down years ago, they converted it into this store. They used the old bank vault as a storeroom. The clerks were horsing around, and one of them shut the door on the other two. Now it's locked tight. And of course the combination is long gone."

"They won't last long in there," Logan said. "What about drilling holes into it to get them some air?"

"We called in to the station when we got here," the cop replied. "But it might take them a while to get anything heavy duty enough to get through.

These old vaults are built with doors a foot thick. I just hope that they can make it in time."

"Shit, we can't just let them smother!" Mike shouted. He strode up to the vault door and looked it over. There were three large hinges, and a large wheel, almost the size of a car's steering wheel, to open it once the combination was entered. He planted his feet firmly on the floor, then grabbed the wheel with both hands.

"Man, what do you think you're doing?" the cop asked.

Mike ignored him, and started pulling on the ring. He sucked in a huge breath and then pulled even harder. Mike's triceps sprang into a huge horseshoe, hard as the iron in a real horseshoe. His huge deltoids bulged as he pit his awesome strength against the door. Every muscle fiber in the enormous shoulders stood out in relief. The veins were throbbing in his neck and forehead. Mike's back was a writhing mass of muscles and veins, popping and straining. He slowly contracted his arms, the biceps starting to contract and balloon out with inhuman size.

"AAARRGH!!" Mike screamed as the door started budging. There was a shriek of metal as first the top hinge, then the second, and finally the third gave way before the stupendous power in Mike's body. Mike yanked the door away, then threw it to the side. The thud that it made when it hit the ground caused the whole building to shake.

"YEAH!!" Mike shouted. Catching Logan staring at him, he crunched up into a most muscular pose. All of the muscles he had just used for his unbelievable feat burst forth once more. Logan started stroking his cock, which had begun hardening when he realized what Mike had intended to do. Mike flexed his arms in a double biceps, the ghastly peaks erupting in a display of freaky muscle. Then he walked into the vault. He returned with the two student clerks, holding each one under an arm.

"They've fainted, but they should still be OK," Mike said as he brought them over. Two medics from an ambulance broke smelling salts under their noses and the guys snorted, then came to. The first thing they saw was Mike standing over them, his huge chest still heaving from his exertions. One of the guys fainted again, and had to be revived all over. Logan came over to Mike and slapped him on the back. "That was incredible, guy."

By now a newsteam from the local TV station had arrived to cover the story of the trapped clerks. The reporter was a young woman who stopped dead in her tracks when she got a look at Mike.

"They said that a huge guy had managed to rescue the guys trapped inside the vault," she finally got out. "Huge doesn't even begin to cover it," she said, licking her lips a little. "How did you do it?"

Mike explained how he had pulled on the vault door until it gave way. The cameraman panned from the wrecked vault to the door lying beside it. "Too bad we couldn't get that," he said.

"How long did you have to work out to get this amazing physique?" the reporter asked.

"Not as long as you would think," Mike replied, and Logan smiled. "Now if you excuse me, we've got to get going."

They walked out of the building, the reporter and camerman still following.

"But surely the hinges on the old vault must have been disconnected, and no one noticed. You can't expect the viewers to believe that you were able to rip the door off the hinges."

"Oh no?" Mike said. Then he looked around and a smile came to his face.

"Maybe they'll believe this. Got the camera rolling?" He walked to the edge of the sidewalk. An old dead tree was still standing in a pit by the curb. It was an old maple, about 30 feet tall. Mike walked up to it, crouched down, and wrapped his arms around the trunk, his hands not quite meeting. He took a deep breath and started straightening up, pulling back as he did so. Cracks began to develop in the concrete surrounding the tree pit.

"Yeah, man, do it, do it!" Logan cheered him on. Mike loosened his grip, bent down again, and again started standing up, yanking harder this time.

His back muscles tightened in thick bands, and his traps spread out in wide slabs of power. Chunks of concrete began to fracture and tumble away from the tree. Mike roared and gave one last mighty yank. As he pulled up the tree broke free from the ground, a huge ball of roots scattering chunks of dirt and cement. Mike lifted the tree overhead and turned to face the camera. Then he carefully laid it down, roared "YEAH!" and flexed his titanic arms in a double biceps, a grin on his face. The cameraman zoomed in for a closeup, and then Mike relaxed. The reporter was speechless, and the crowd had stepped back, shocked. Logan came up to him and grabbed one of his huge arms in both of his hands. "Mike, that's going to be on every news station in the country tonight!"

"Yeah, well, there will probably be many more shows after this one. It really turns me on to show off! Let's go," Mike said.

"My house is only a few more blocks from here. We'd better hurry or I'll start ravishing you right here." Mike saw that Logan's big dick was starting to stretch the material in his sweatpants and he grinned.

They hurried the rest of the way and as soon as they were in the house Logan grabbed Mike and wrapped his own sizable arms around the muscle giant. "Such incredible power - if I hadn't seen it myself I'd probably not believe it," Logan said. "Your strong muscles are so sexy, I can't control myself."

"Yeah, it gets me hot and horny too, knowing that I'm the epitome of muscle and power," Mike said, and broke free to flex his arms for his adoring buddy.

"And you're almost perfect yourself. Take those clothes off so I can dig your own crazy muscles."

Logan quickly obliged, whipping the tank top over his head to expose his rugged pecs and chiseled abs. He pushed down the pants and stepped out of them. His thick cock bobbed in front of him, already hardening again at the thought of sex with his buddy. Mike's own horse-sized schlong had begun to harden as Logan was stripping, and it finally burst the strained seams of the shorts he had been wearing. The 13 inch monster stood out at attention, and Mike stepped closer so that it was rubbing up against Logan's own 11 inch tool.

"This way, big man," Logan said and he picked Mike up. Even though the larger man weighed over 500 pounds, Logan's strength after his own muscle growth was more than enough to handle Mike's weight. Logan walked into the bedroom while Mike ran his hands over the knotted slabs of beef in his arms and shoulders. Logan stopped at the side of the bed and laid Mike down onto it, then got on top of him. They kissed long and hard as Logan rubbed his chest against Mike's, Logan's stiff dick thrusting between Mike's mammoth thighs, rubbing against Mike's large ball sac. Mike held the scientist tightly, his hands pressing firmly into the firm broad back of the stud on top of him.

Mike pressed on Logan and the top man yielded so that they were lying side by side. Mike shifted around so that his face was positioned in front of Logan's erection. He took the cock into his mouth, working the long shaft down his throat gradually. Logan groaned and bent down to lick the bigger man's bigger prick. His tongue darted and swirled around the fist sized head of Mike's cock. Clear drops of pre-cum appeared, and Logan tasted them greedily. Meanwhile, Mike had started rhythmically working on Logan's dick.

His lips slid along the veiny cock as he sucked. One hand caressed and stroked Logan's balls as he slurped on the thick cock. Logan followed suit, sucking hard on Mike's tool, taking it in as far as he could without choking on the beercan thickness. Logan thought it was almost like sucking on one of the barbell bars at the gym, so hard and thick was Mike's superman organ.

Both men kept up the sucking, and their hands wandered as far as they could along each other's rockhard muscles. Moans of pleasure came from both of the two studs as they brought each other to climax. Mike shot first, forcing jets of hot cum down Logan's throat. The first squirt was enough to bring Logan off himself, and cum started gushing out of his own cock into Mike's mouth. Roars of ecstasy came from both musclemen as they shot over and over again into each other's hot mouths.

When Mike had managed to milk the last drops from Logan's prick, he shifted around so that he could lay alongside of Logan. Logan turned onto his side and put his arms as far around Mike's huge traps as he could and gave him a tight hug.

"Careful! You don't want to break all of my ribs," Mike said with a smile. Then he brought his handsome face up to Logan's and pressed his mouth against Logan's. As they kissed, they flexed their massive muscles for each other's enjoyment. Mike clenched his fist and squeezed his biceps into huge mounds of obscene muscle. Logan made his washboard stomach jump into relief and made his pecs erupt into striations of sinew and power.

"Mmmmmm!" Mike finally purred as he squeezed Logan tightly. "Getting super big muscles has gotten me super horny."

"Yeah, that's what I found," Logan replied. "The week after my own rapid growth I was jerking off several times a day. And now that I'm even bigger, I feel like cumming every hour. More, now that I've got you around!"

"Yeah man. And when we get the machine fixed and pack more muscle onto you, it will be even hotter," Mike said as he looked into Logan's eyes.

Experimental Muscle, Part 4

I decided to bring these guys back for another installment. The standard disclaimer applies: this story is a work of fiction which contains descriptions of sexual activity. If you are under the age of 18, do not read any further.

The next morning Mike and Logan didn't wake up until past ten. The muscle growth formula had given them huge size and strength, and it had also revved up their sexual drive. Several times during the night either Mike or Logan would wake the other to start another round of steamy sex. Logan had had to put his king-size mattress on the floor, because he didn't think that the platform bed would be able to hold their combined weight of over half a ton. Certainly not the time that Mike was pile driving his cock up Logan's ass with ferocious intensity, slamming Logan's body so hard against the mattress that the whole house shook with the jolts. Because it was Saturday morning Mike didn't have to go to class nor Logan to work at the lab, so they turned to each other and started kissing.

Logan shifted himself so that he was lying on top of Mike's body, pressing his thickly muscled chest into Mike's enormous pecs. The young scientist brought his face toward Mike's, smiled, then pressed his lips against Mike's. Mike's tongue immediately reached for Logan's, and they kissed deeply as Mike squeezed Logan's hard body tightly against his own rock-hard torso.

"Flex for me," Mike begged. "I can't get enough of those gigantic arms." Logan smiled and knelt straddling Mike's tightly ridged midsection. Then he quickly brought his arms up and blasted into a double biceps pose. Mike moaned as he sat up and felt the dense masses of muscles that formed Logan's 28 inch arms. He traced the veins that coursed along Logan's thickly corded forearms with his fingertips, then returned to handle the granite biceps that Logan kept flexing. He lifted up one arm and drove his face into Logan's left armpit, tonguing the sensitive area. Logan swung his arm around Mike's head and pressed into it so that the younger man was surrounded by hard muscle. Mike revelled in the sensation of being virtually encased by the hard flesh that felt like moving stone. But eventually he wanted to move on, and strong as Logan was, there was no way he was as powerful as Mike.

Mike forced Logan's arm back by pushing on it with his neck and shoulder. He easily freed himself from Logan's grip, and now it was his turn to kneel on the bed and flex. Mike slowly raised his arms out to either side of his body and raised them up til they were parallel with his shoulders. Then as Logan looked on in rapt attention, Mike slowly started to bring his fists towards his shoulders. The huge biceps started to bulge with size, then suddenly the flex had reached a critical point and the knot of his bicep peak quickly formed on top of the fully flexed arm. Logan still could hardly believe the size of Mike's arms, but he had measured them in the lab last night, and he knew that they were 36 inches around. And when Logan thought of the incredible feats of strength that Mike had done with those arms and his other gigantic muscles, Logan's cock started to leak pre-cum.

Mike's own cock had stiffened to it's full length and was throbbing in front of him. Logan shifted around on the mattress so that he could take Mike's thick tool into his mouth. He almost gagged on the purple-red head, but then his throat relaxed and he was able to get the full shaft into his mouth. As Logan started moving his head up and down on the monster cock, Logan kept flexing his arms, puffing up his chest, even managing to do a kneeling most muscular pose. Mike's paper-thin skin let the ripple of every sinew show as he struck each pose.

Logan was panting now as he applied a strong suction to Mike's dick. He was fisting his own dong now, moving his hand in time to the movement of his head on Mike's cock. Logan craned his neck so he could watch the bigger man flex some more and he was overcome by Mike's size and animal masculinity. Mike's arms were as big around as the waist of a normal man and the peak of his biceps was as large as most men's entire bicep. Veins tracked all along the cords of muscles on Mike's forearms. Logan sucked harder, utterly worshipping the huge stud before him. Waves of intense pleasure struck his cock and he started to shoot cum in rapid bursts. Mike knew that it was his own muscle that Logan was getting off on, and that thought, along with the expert blowjob he was getting, was enough to send him over the edge again. Logan grunted as blasts of spunk shot out of Mike's cock and into Logan's hot mouth. Both men were able to cum in huge amounts, even though they had shot eight loads in less that 20 hours. They had Logan's muscle growth factor to thank for that.

Once Logan had sucked the last drop out of Mike's cock he pushed himself up and kissed Mike. Mike could taste some of his own salty cum on Logan's tongue. After they had kissed several minutes Mike said, "Let's get something to eat. I'm starved! Then let's see if we can get you to grow even bigger so that you're my size, or larger!" They went into the kitchen and started pulling things out of the refrigerator and cupboards, making an enormous breakfast of eggs, steak, a loaf of bread into toast, a half gallon of orange juice and milk for each of them. When they had finished packing away the food, Logan said, "Let's get cleaned up, then head for the lab. I should be able to repair the burned out growth factor generator."

Logan and Mike headed to the bathroom. Mike preceded Logan, and the scientist thrilled at the sight of what his discovery had been able to do.

The muscle growth formula would be able to make anyone bigger than the biggest bodybuilder and stronger than any powerlifter. Mike's back was crisscrossed by muscles that twitched even as his arms swung from side to side. When he chose to flex his back muscles, the result was incredible.

Logan turned on the shower and when the water was hot turned to Mike and asked with a smile, "Care to join me?" He stepped into the shower and Mike followed. Logan handed Mike a bar of soap and moved around under the showerhead so that his body got all wet. When he lifted up his arm Mike moaned at the sight of Logan's serratus muscles ridged beneath the flaring lat muscle. Mike started soaping up Logan's hard body, working the lather over the dense mounds of pec muscle. He continued up to Logan's broad delts and then reached around his wide lats to Logan's back. At that point Mike held Logan tightly in his arms and started to rub his own massive chest against Logan's. The lather let their chests slide easily back and forth as the two studs kissed deeply. Mike moved one hand down to Logan's cock which had started stiffening. He stroked the thickening shaft, then brought the hand that held the soap around and created a lot of lather. He brought the soapsuds to Logan's dick which was now fully erect, all 11 inches throbbing as Mike swirled the suds around the purplish head. Logan started thrusting his hips so that his cock slipped all the way through Mike's encircling fingers.

"Hey Buddy, why don't you use that soaped up rod to do some deep cleaning?" Mike asked as he turned his back on Logan. The other man needed no further invitation and he grabbed his prick in one hand and pressed it against Mike's ass crack. Logan forced the cock head into Mike's butthole and it slid in easily as Mike relaxed his sphincter muscles. Mike grunted when the cock was fully inside him and he could feel Logan's hard abs pressed up against his lower back.

Logan took the soap from Mike and swirled it all around the huge back and chest in front of him. Logan slid his soapy pecs along the gigantic man's back, feeling the rippling muscles as Mike pressed back against him. Then Logan started soaping up Mike's own tool which was now its full 13 inches of steel pipe hardness. He fisted the huge dick as he started slamming his own rod in and out of Mike's tight ass. Logan fucked Mike as the warm water from the shower continued to spray down on them. He moved his mouth over to Mike's ear and thrust his tongue inside, then gently bit the side of the ear and the lobe. Logan worked his mouth down to the side of Mike's neck, which was thick as the thigh of an average man. His tongue licked along the bigger man's neck as he continued thrusting his dick deep inside Mike's ass. Logan had his other hand tightly clamped on one of Mike's pecs, and the hardness of the muscle he felt there drove him to fuck Mike all the harder. His fingers pinched the nipple there and Mike groaned.

"You like getting fucked by a big muscle man, right?" Logan whispered in Mike's ear.

"Yeees," Mike moaned in reply.

"Like to feel a strong man hold you tightly while he plugs your ass with a big muscledick?"

"Love it man! Fuck me stud!"

"Wait til later when we get the machine fixed. Won't believe the huge muscleman that will be fucking you after I'm through growing."

"Yeah man! Bigger and stronger muscles for me to feel. Gonna shoot just thinking about how huge you'll be Logan," Mike gasped out.

Mike started to shoot his load. Immediately Logan felt the contractions in Mike's ass gripping his cock as if the big man's powerful hands had been squeezing it with all their strength. The force was too much for Logan and he began to empty his balls into Mike's ass. Mike's cum was splattering against the shower's wall, slowly sliding down the wet tiles. Logan concentrated on the squeezing his cock was getting, the sensations that were being sent through his cock which was now trapped in the muscular contractions of Mike's glutes. When Mike had shot his ninth glob of cum, his ass muscles relaxed enough for Logan to shove his dick in up to the hilt one last time. Once again Logan nibbled and breathed into Mike's ear, murmuring, "Gotta go now and fix that machine so that I can grow bigger for you. Then get you bigger too."

Logan slowly withdrew his dick and the two men gently finished washing each other off. When they were rinsed off they grabbed several towels each to get dry. Logan had some XXL shirts that were just big enough to fit him and Mike, though they had to rip the front open a bit so that the shirt wouldn't rip at the seams on Mike. They slit up the sides of a pair of shorts so that they could accomodate Mike's monstrous thigh muscles.

"We should stop off and get some clothing made up. These things won't fit either of us before long," Logan said. "Here are some sandals that you should be able to fit into."

They walked out to Logan's car - a Honda Prelude. They both looked at it, then laughed. It was ludicrous to think that Logan, let alone Mike who stood just over 7 feet tall would be able to fit comfortably inside.

"I guess we walk for now," Mike said.

They started off for the lab, getting stares from everyone that they passed on the street. They were both getting off on how people were stopping in their tracks as they approached, some even pointing and saying things like, "That's the guy who was on the news last night. The guy ripping the tree out of the sidewalk." They decided to go directly to the lab, rather than stop for clothing. If Logan could get the machine working again, their bodies would grow, making any measurements this morning obsolete.

Logan unlocked the lab and flipped on the lights. He walked over to the machine and started taking off some panels, pulling out circuit boards and other components. Mike went over to the gym area to amuse himself while he waited. He loaded 8 45 lb plates onto a bar, then got it to balance on two fingers of his hand. Mike curled the weight with the two fingers, stopping after 20 reps. Not because he was especially tired, but because the barbell was slipping and he didn't want it to crash down and disturb the scientist while he was at work. He looked up and caught his image in the mirror. He was freakishly huge, the clothing on him stretched tightly over his muscles. And he was more powerful than he had ever dreamed of being. Mike could feel his cock hardening again, swelling in the shorts and beginning to poke out of one of the leg holes.

"This should do it," Logan said, breaking Mike's reverie. Mike stood up and Logan smiled when he saw the firehose hanging down alongside one of Mike's gigantic thighs.

"I started making a batch of growth factor that's keyed to my genetic makeup," Logan said. "The factor I gave you last night was about 10 times as potent as the one that I originally took. So now I should grow at the same amazing rate that you did."

"What's the limit to growing?" Mike asked.

"Don't know," Logan replied with a smile. "I guess we'll find out. I made a double batch, and because I can't wait to get at least your size, I'm going to down it all at once." With that Logan picked up a gallon sized plastic beaker and started drinking the thick solution.

The two men looked at each other expectantly. Mike's dick was sticking down the short leg, starting to tear it at the slit they had made earlier.

"I better take these off for now, before I rip them to shreds," he said as he carefully pulled down the shorts that were hugging his huge thighs.

"Funny, I'm starting to feel cold, not hot like the other times I drank the solution," Logan said.

"Well let me warm you up then," Mike said. He wrapped his enormous arms around Logan and squeezed the scientist against his chest. "Let me feel those muscles as they grow," Mike said. He still towered over Logan, but not for long he thought. He picked Logan up as if he was a small boy and set his feet on a nearby bench. Now the difference in their heights was negated and Mike grabbed Logan once again. Logan put his own arms around Mike, trying to see if his hands could meet on the far side of Mike's broad back. They just barely met. The two men began kissing and Logan sighed as Mike's tongue flicked around in his mouth.

Logan shivered a little from the cold, and stood on his toes to keep his mouth level with Mike's. He rubbed his hands across the hills of muscles that rippled along Mike's back and lats. Logan pressed into Mike and reached around once again. He stretched, but his hands couldn't meet. Mike was bending down a little now, keeping the passionate kiss going. Suddenly, he drew back.

"Logan, what's happening? You're getting smaller!"

It was true. The top of Logan's head was level with the base of Mike's neck, not at his nose as it had been before. Logan realized that it was impossible to reach around Mike's back because his arms were shorter than they had been. What was going on?

It was now obvious that Logan was getting smaller. It was visible to the naked eye as he got shorter and smaller. His proportions remained the same, but Logan was definitely shrinking! His teeth were chattering now because he was so cold, and his body was convulsed with shivers, not from fear, but from the freezing sensation. Mike was the one who was more afraid. Logan was already only half as tall as Mike. What had gone wrong?

"M-M-Mike, bring me to the m-m-m-achine," Logan stammered. Mike picked him up and brought him over to the control panel of the growth factor machine. On the way he picked up one of the torn tee shirts lying on the floor and wrapped it around Logan, hoping to warm him up a little.

Logan tried to look at the dials and control knobs of the machine, but he found it hard to concentrate. He was freezing! But it seemed as if the rate of shrinking had started to slow down. But Logan was already child-sized, the size of a ten year old boy. But a boy with the perfect proportions of a bodybuilder.

"Mike, open up this panel by pressing here," Logan said as he pointed. Mike did so and Logan looked at the wiring and circuitry inside.

"Thank God, it looks like you stopped getting smaller!" Mike cried. \

"Yeah, I feel like I'm starting to get a little warmer too," Logan said. "But look at me!"

Logan was now barely a foot tall. The hair under his armpits had disappeared, and the stubble on his face had disappeared. He still retained his relative muscle size, but now his flexed biceps would have been the width of one of Mike's fingers.

He turned back to the machine and then said, "Here it is. When I fixed it, the polarity was reversed. So it produced a formula that reduced size, rather than increased it. Because of other changes I made it made me smaller instead of less muscular. Mike, move this lever over here," he pointed. Mike did what he said and then Logan said - and flip this switch the other way. Now press this button and put the flask under the spigot."

Mike did what he said and the machine started humming.

"That should do it," Logan said.

"What if this doesn't?" Mike asked.

"Let's not worry about that," Logan said. "Might as well put me down, it will take a while for the formula to be produced."

When Logan was on the floor he looked up at Mike. He towered over Logan, almost seven times taller than the little man. Logan lost all concern about his diminished size.

"Mike, you are really a giant to me now," Logan said. "I wish you could see the view from here!"

Mike looked down at Logan, relieved that he had not disappeared.

Logan whispered, "Flex for me musclegiant."

Mike brought his arms up and the titanic bicep peaks blasted forth. He turned to his side and flexed a calf muscle that flared to its greatest width over Logan's head. The tiny scientist reached up and ran his hands along the diamond of Mike's muscle. Mike could see that Logan's dick had stiffened out and was pointing out, straight out from his minuscule muscle body. Mike's own cock started to harden as he thought of the sight that Logan was treated to. Even though he had been afraid of Logan's shrinking, Mike now was getting into the fantasy aspect of his huge size relative to Logan. It was like he was the Jolly Green Giant! He looked down as Logan started to stroke his cock, not much longer that a matchstick.

"Come here little buddy," Mike said, and scooped Logan up in the palm of his hand. He held Logan in front of his pecs, then squeezed them together so that the striations of muscle snapped into view. Mike's pecs were higher than Logan was tall, and the small man gave out a moan as he bent forward and placed his mouth on the vast plateau of Mike's chest muscle. Mike moved his hand so that his right nipple was within Logan's reach, and Logan got the huge protruding nipple into his mouth. Mike sighed as he felt the warm liquid of Logan's mouth over his nipple, stretching Logan's mouth as wide open as it could get. Logan's tiny hands were trying to grip into the titan's hard chest, but he could hardly make a dent into the dense musculature.

Mike's put Logan down on one of the weight benches and sat on the other end. Mike's cock, which seemed huge to Logan when he was normal size, now towered high above him. It was longer than Logan was tall! Logan reached up as high as he could, running his hands along Mike's thick shaft, rubbing along the pulsing veins in the thick cock. Pre-cum had started to drip out, and a glob fell on Logan's shoulder, which he wiped off and smeared over his own chest. He then rubbed his muscle-mite pecs against Mike's throbbing rod. Mike sighed when he felt the hard pressure of Logan's small but hard muscles against his dick.

Mike stood up and gently picked Logan up. He lowered Logan down until he was straddling Mike's cock. His legs were spread widely to keep on top of the shaft. Logan was pumping his own dick with one hand, while he felt the huge cock underneath him. Mike looked down into Logan's eyes and saw the spacey-eyed devotion in his face. Logan was looking up at the ultimate muscle giant, and he was almost slack jawed as Mike flexed his enormous bicep once again. Mike was in his own fantasy world, picturing himself as a giant 40 feet tall, a mountain of muscle and power. He could feel his balls tighten, he was getting off on this so much.

"Musclegiant, I want to see you cumming," Logan said. He was jerking his own cock wildly as Mike's throbbing member bounced him up and down in the air.

"OK buddy, here comes a shower for you," Mike said as he stood up, letting Logan slide off onto the bench. He started fisting his own dick and Logan stepped back on the bench to get a better view. Logan craned his neck back so that he could see the battering ram that Mike held in his hand, the head thick and purple colored. All of the muscles in Mike's body were in sharp relief, and Logan knew that he was going to lose it any second. Suddenly, Mike started to grunt and cum started to spurt out of his piss slit. The first two loads went flying off into the distance, but the third one splattered down and almost knocked Logan down. At that Logan's dick started to spray it's own load of cum as Logan smeared the thick spunk of the muscle giant all over his hard body. The bench was slick with cum and Logan fell into it, exhausted, as Mike stood over him, seemingly miles high, a few more spurts shooting out of the cannon-sized dick.

A minute later Mike picked up Logan once more and brought him up to his face. He stuck his tongue out and lightly ran it along the tiny muscleman before him, wiping off the remainders of his spunk. Logan loved the rough, warm and wet feeling of Mike's tongue all over his body.

The reverie they were experiencing was broken by the beeping of the muscle growth machine. Mike walked over to the machine, carrying Logan, and they could see that the large container had been filled to the top with a new solution.

"What if your change didn't work?" Mike asked. "If you got much smaller, you might disappear altogether!"

"I'm sure that it's OK," Logan replied. "And I increased the growth factor rate. I should get as big as I was before - and bigger. There's a spoon over by the desk. You better get some out so that I can start drinking it."

Mike retrieved the spoon, dipped it into the viscous solution and held it in front of Logan. Logan bent down and slurped up the formula. Mike continued spooning it out to Logan, until his stomach was distended and he couldn't drink anymore.

"Well?" Mike asked, looking inquisitively at Logan.

"I think it's starting to kick in," Logan said. "It feels like it's getting warm in here."

A minute later he asked for more formula, and Mike continued spooning it out.

"God, it's boiling in here," Logan said.

"Nothing's changed - it must be the formula," Mike said. "Hey, it's working, you are getting taller."

Logan was indeed growing. The formula's action had been slow to start, but once it did, both men could see the progress that Logan was making. He quickly doubled in size, and Mike held the container up so that Logan could drink more. Sweat was pouring off Logan's body, dripping onto the bench he was standing on, forming a puddle around his feet. Soon he was four feet tall, and jumped down onto the floor. He walked over to the growth machine, pushed a button, then standing on tiptoe, placed another jar under the spigot. The fluid began to pour into the jar as Logan drained the first one. Mike was staring at him as he started to grow taller. But Mike could swear that Logan was getting thicker and wider as well, not just regaining his previous stature. Logan was now about 5'6", and probably about 200 lbs. The machine beeped again and Logan grabbed the beaker. He started to chug the solution down, his adam's apple bobbing as he gulped it down. He looked at Mike then, grinned, and flexed his arms. Even though he was still smaller than before, his arms were gigantic. Mike smiled too as he felt his buddy's right arm muscle.

"Going to get really big for me now, stud?" he asked.

Logan moved into a lat spread and said, "Bigger than you ever dreamed anyone could be, I hope."

And he was well on the way there. Now just over 6 feet tall, Logan was slightly taller than when Mike first met him. But he was more massive than he was then. His pecs were swelling as he gulped in air, trying to keep the burning sensation in his muscles from becoming too intense. He straightened his arm down and the tricep muscle was thick and dense. Mike licked his lips at the sight of the bulging curves of the muscle, criss crossed by striations of the different fibers coursing down Logan's arm. Logan flexed his calf muscles by standing on his toes, which also made him as tall as Mike, at 7'1". They both looked down at the wide diamond-shapes that were in perfect proportion to the massive thigh muscles.

Logan continued growing, and now he stood taller than Mike, and he was more muscular too. Mike's cock had started hardening, and he began to run his thumb and two fingers along the shaft as Logan flexed and posed for him. Logan was still covered in sweat which ran in rivulets down his shoulders and chest, dripping off his stiff nipples, collecting in the deep crevice between his pecs. Mike bent down so that his face was in the middle of this muscle monster and started licking the sweat with his tongue. Logan put his hands on Mike's head and pressed it into his midsection. Mike was surrounded by hard, sweat-drenched muscle. Logan's pecs pressed against his forehead while Mike's tongue worked the ridges of Logan's six pack. And the leg-sized forearms and massive biceps were tight against the side of Mike's head.

Logan forced Mike's head downward, and the younger musclestud did not resist at all. He even wondered if resistance was possible - Logan was now about 7'6" and at least 150 pounds heavier than Mike. And every ounce of those pounds was sheer muscle and sinew. Mike gladly took Logan's swollen cock in his mouth. The prick was now at least 14 inches long, and thicker than Mike's own horse-sized dick. Mike worked it down his throat until Logan's pubic hair was tickling his nose, and he breathed in the heady musty scent of Logan's crotch. Logan kept his grip on Mike's head and gently but insistently forced it back and forth on his cock. Mike ran his hands all along Logan's legs, pillars of hard muscle. He looked upward as he pulled away from the cock and saw Logan looking down, his face just visible past the shelf of his pecs.

"I wanted you to be bigger than me, and now my wish has come true," Mike said, then took the giant cock back in his mouth. Logan grunted - the heat was dissipating now that the growth seemed to have stopped - but the sensation of increased power remained, and Mike's sucking pressure was heaven. Mike grasped Logan's glutes, then began working one finger into Logan's butthole. Logan groaned out loud and began to fuck Mike's face. Mike was able to keep the sucking going, his tongue sliding along Logan's monster meat before Logan would ram it back down Mike's throat. And his index finger was now deep within Logan's ass, adding to the pleasure that Logan was feeling.

Logan looked down and saw that Mike was completely enthralled by his massive body and huge cock. He was in complete control of the situation, and Mike was willing to let him be. A musclestud, completely worshipping a bigger musclestud. And there was no question that Logan was bigger than Mike, actually bigger than any muscleman that ever lived. Logan felt his balls contracting, getting closer to his body.

"Mike, you're gonna make me cum. I'm going to shoot my load into your mouth. My muscle cum is going to pour down your throat."

Mike worked the cock even more than before, and now had three fingers slamming into Logan's ass, banging against his prostate. He wanted that juice badly, and he was going to do what it took to get it.

Logan bucked his hips, threw his head back and yelled because the intensity of the orgasm was so great, both from Mike's expert cocksucking and from the extra sensitivity from the recent growth spurt. His balls pumped semen into Mike's eager mouth, and Mike started to gulp it down. Wad after wad shot into Mike's mouth and he labored to get every drop. Mike was so turned on by the massive cum shot that his own dick, which had been dripping all along, began to shoot a stream of cum onto the floor. As his cock exploded he looked upward and saw Logan flex his arms overhead in a double biceps pose, which got him so excited that the third spurt shot farther than the first two.

When Mike had milked every drop from Logan's dick and his own dick had finished dribbling, he got to his feet and put his arms around Logan. Logan bent down slightly and the two kissed passionately, their tongues meeting, exploring each other's mouths.

When they broke the kiss, Logan smiled and said, "Sorry, but that growing has made me famished again! Let's get something to eat, and then we can have a major posing session for each other. Then we can see if you can catch up to my size," and Logan flipped a switch that would start to fill up beakers of growth solution.

They got dressed again, Logan being very careful that he didn't rip the clothing he had come with, which was now several sizes too small. They left the lab to go back to his house, joking about the commotion that their enormous bodies would cause when they hit the street.