"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." •