Grow and get huge

by Massiveboy

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I met Mark at the gym after eight on Sunday. Mark always liked to meet on Sundays because that was the one night when the gym closed early. Mark was warming up when I got on the floor. He looked even bigger than he did last Sunday. A lot bigger. Mark is a huge bodybuilder. He's 6’3”and last week he weighed 284 pounds. His arms were 22”, chest 55”, waist 33”, Quads 29”, calves 19”. Now he looked 30 pounds heavier. He was wearing a tight white tank top which barely could contain his massive upper body. His muscles were starting to look freaky. His pecs jutted out like a huge shelf. He was on the incline bench pushing up a bar with 225 pounds. That weight was like a twig to Mark. He pumped up it up and down 12 times and when he had finished he sat up and flashed me a smile.

I told him, “You look like you've gained 30 pounds since last week.”

“I have. I'm on a new program.”

“Your chest looks awesome.”

Mark smiled and effortlessly bounced his pecs. They bunched up under the shirt stretching the fabric. Mark knew I loved his pecs and he got a kick out of showing them off.

“Your arms look bigger too.”

“I've put on an inch since last week.”

He had. Mark raised his right arm and the bicep peaked into a small mountain. As he held the pose, more and more veins popped out.

“Give it a squeeze.”

My hand reached out and gripped Mark's arm. The muscle felt like a rock covered in velvet. His arm was so big that my hand looked puny next to it.

“So what's this new program.”

“I'm part of an new experiment in human muscle growth for the University. I started last week. Dr. Miller gives me a shot once a week and then I drink three genetically engineered protein shakes each day. I swear to God, I can feel my muscles growing right now.”

It looked it to me. Ever so slightly Mark's muscles seemed to have a slight tension running through them. It was as if his body was constantly on the verge of flexing. It almost did seem as if his shirt had gotten tighter since I walked in.

“I can't wait to work out every day. I've gone through two shirts this week. And this one won't make it through this work-out.” Mark picked up two 180 pound dumbbells, the heaviest ones in the gym and started doing a set of incline flies. I watched in awe as his huge pecs just swelled each time he pushed the dumbbells together over his chest. His head was buried under his huge chest. Each rep seemed to make his pecs just get bigger.

Mark said, “These weights just seem to get lighter with each rep. I can feel my pecs just getting bigger and bigger.” Mark's shirt was now completely tight and it seemed to get tighter with each rep. He was growing before my eyes. I heard the first rip. Mark moaned in pure pleasure as he felt his body growing. The pecs just caused a huge rip to appear over his right nipple. Mark threw the weights down and sat up and as his huge chest just filled out the shirt to the bursting point. Mark smiled and flexed his boulder sized pecs and the straps on his tank top snapped. It was the sexiest thing I had ever seen.

“Feel 'em. I know you want to.”

I put both my hands on his pecs and they pushed against my palms not from any action of Mark's but because they were growing. I almost fainted when I realized this.

“This is nothing. Watch my arms when I curl.”

Mark picked up a barbell loaded with 225 pounds and picked it up and started to curl. That was 125 pounds more than he had used the week before! His first rep he strained to bring it up. Then he started to curl faster and with more control. His biceps rippled and swelled. Every vein was visible and the then they grew. I could see the big vein running down his bicep just inflate. His arms looked like you were inflating them with a bicycle pump. Mark closed his eyes and was clearly turned on by his own growth. Every rep made his arms get bigger and bigger………

“Measure them.” Mark had set down the bar and stood slowly flexing his massive biceps in the mirror. He was a muscle freak. His gym shorts were gone. Every part of his body was now growing and Mark grabbed a blender of protein shake and chugged it. Every gulp make him grow. His thighs, his back, his neck. He flexed in the mirror and laughed. “I'm not even gonna bother with clothes if this keeps up. I see you're enjoying this as much as I am.” Mark took my hand which looked puny in his hand and ran it down his chest and over his abs. He was growing. Mark then picked me up and held me a food off the floor. I grabbed a tape measure and wrapped it around his flexed arm. 33 inches of rock hard muscle. The bicep quivered and stretched the tape as he held the pose. “It'll keep growing all afternoon.”

I measured all of him and stood in shock. He had gained 29 pounds in this one work-out. Mark then suggested a nap. I shouldn't say suggested. He just said, “We need a nap.” and then picked me up and carried me in back to a cot. He overfilled it completely and then wrapped his huge arms around me and held me to his body. He fell asleep immediately but I couldn't sleep because with every breath he took I could feel his muscles growing. It made me incredibly horny. I turned to look at this huge man. My hands roamed over his unbelievable muscle. His arms and pecs were monstrous and thick. His abs were like rows of hard muscle. He woke up and smiled at me and then ran his huge hands over my body until I came and then he said, “Go to sleep now. When you wake up. I'm going to be an entirely different man. You'll wake up with a new body to explore.”

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