Liz wasn't as strong as she thought

“Liz! Are you alright?” He shouted as he approached her muscled form as she sat up and turned. Josh slowed stopped next to her and put his hand on her shoulder, noticing how he didn’t have to bend down to her at all “What happened… ?” He asked, simultaneously noticing that even on her butt her head was higher than his waist. He admired how firm her round shoulder was, bulging twice as large as a softball.

“Heh, sorry! I thought I had to be twice as strong as superman by now,” she said lifting the arm he had his hand on and doing a flex showing a muscle that looked proportionally as large as the largest female bodybuilders he’s ever seen, causing his hand to slide over its soft yet firm bulge in admiration, “and I tried lifting, um, 645 with one hand thinking it’d be easy. Hee hee.” Josh laughed with her while cautioning her that she is very strong but she’s no superman, while still caressing her still raised bicep. Liz was very much enjoying it. “Maybe I’m not that strong yet, but I’m a growing girl!” Josh gulped realizing that she may grow strong enough to lift it with one hand by the end of the day if he can’t control himself. “And my biceps want to get bigger so there will be more for you to touch after all josh…” she bounced her bicep with his hand on it, causing him to realize what he was doing and remove his hand. “I bet it’ll be big enough for two hands by the time I can lift this!” She gestured to the barbell. This excited Josh, but also made him think for a second.

“Wait, so you were able to unrack that with one hand?” She nodded adding that she dropped it immediately sounding slightly upset. “Wait, maybe you could lift it if you showed proper lifting form for once. It might be difficult, but if you lift the right way I think you could do it.” Liz’s eye’s brightened and she got on her knees.

“Really? What do I need to do?” She said alertly, her huge breasts now nearly touching Josh’s chest as her eyes were just above his while on her knees, a fact that slightly excited him, as her limp and slightly leaking nipples extended past him on either side. Josh swallowed and talked more steadily.

“Well first you roll that weight into the middle of the room, and I’ll go get a belt for you.” She smiled and nodded while getting up, he gasped again as her breasts rose above his head before she turned towards the weight, unaware of his staring. He shook his head and went and got a lifting belt and some chalk for her. “Alright now stand in front of it and put this on.” She took the belt and strapped it in; despite being so big and muscular, her waist was proportionally much smaller than most girls, and resting above her hips it was fastened on the same beltloop as Josh uses. As josh saw her huge cock swinging around her knees, he decided for her own safety that she put something on, to keep that monster out of the way or hitting it when she dropped the weight. In the storage room of the basement there were boxes of old clothes, including their mother’s maternity clothes. He tossed her the chalk and said he’d be back. When he returned with a very large and elastic pair of spandex shorts, he saw that Liz was still very much a novice as she used way too much chalk and had two pure white hands. “Woah on the chalk! I know you have larger hands than me but you don’t need that much, just enough to keep your hands dry!” Josh laughed as he handed her the large pair of spandex. “So you don’t’ injure your ‘friend’ there. Its from when mom was pregnant with you. She was overweight too then so you should have plenty of room.” Liz blushed, realizing she was naked, which didn’t bother her while she was so aroused and seductive, but felt embarrassed now that she was feeling more normal. “And here, these are the bedsheets I tore up to make curtains for my treehouse however long ago. It should be able to cover you.” He handed her what looked like a blue bedsheet, cut down the center lengthwise to be a 2 foot by 6 ½ foot strip of cloth. She put on the spandex, and pulled the drawstrings tight as there was plenty of slack outside of her thighs. And she wrapped the sheet around her breasts, having josh tie it in the back, with still a couple feet of length left. “Now we’re ready” he said walking to her front, slowing to look up at her large breasts shrinkwrapped by the sheet. The tubular lengths of nipple meat folded down along her breasts, with two tiny wet spots forming at the ends.

“What now Josh?” Liz said excitedly, causing Josh to look even higher to her cute excited face.

“Okay, now bend your knees and squat down, position your hands wide on the bar for a good grip, and keeping your arms and back straight, lift with you legs. Then squat again when you are straight, only this time pulling your arms to your chest, then stand back up attempting to get the weight over your head.” Liz listened intently then nodded. She grabbed the bar then with medium effort, stood up.

“I guess this is pretty heavy!” She said surprised, she then did the next step of getting the bar up to her chest and inhaled sharply. Josh noticed now that her arms and legs looked slightly swollen from the effort. But then with a large grunt Liz thrust the weight over her head and let out a low growl, “Arrraahhh!” she said triumphantly. He arm and leg muscles pulsated with blood as she breathed heavy, her chest rising and falling dramatically, and he could see her nipples strain the sheet with the increased bloodflow, but stay put. “Thanks Josh, I didn’t think I could do this! Now what though?” She said starting to shake as her arms were getting tired.

“Oh, step back as you drop the weights forward to the floor.” He said backing away. A very deep *DONG* sounded as the weights hit the thick mat and Liz stepped back. Her large foot prints staying in the mat for a little bit. Her whole body was pulsing, but she didn’t’ look like she grew at all. Even the large bulge in the front of her shorts was pulsing, which Josh hoped was all it did.

“Thank you so much Josh!!” Liz said smiling, and hurring over to him and scooping him into her arms easily. Squeezing him close into her breasts she hugged him, “If you didn’t believe in me I wouldn’t have ever done it!” She said and kissed him on the cheek. Josh was very turned on and his erection was barely touching her abdomen. Liz’s eyes widened with a slight amused surprise look on her face. “I’m glad you are here to help me discover everything about my new bigger body. I know you never paid any attention to me before, so I know you are just being a nice big brother to me. I’m sure as a weight lifter your self you are just academically interested in whats happening to me right?” She squeezed him closer, pressing his erection into her abs. He went along with it and anxiously nodded his head. “Well I guess you’d want to document as much as you can then, grab the tape measure.” She said smiling, lowering him down, dragging his cock along her body as it rubbed across her bulge just before touching ground, now with her junk in his abs. He took a breath with his head nestled slightly in the bottom of his sister’s breasts, then turned and walked over to pick up the tape measure. He turned back around to Liz, and she smiled and did a double bicep flex. “Lets start here.”