It was hard for you to look inside the machine, but you somehow manage to see Brenda jump a little, while at the same time discover why she did it. The machine had a syringe which poked Brenda in either the back, or butt judging by the fact that she was standing in front of where the needle was positioned.
Just then, you notice Brenda get two inches taller than she originally was, and you could also see some biceps sprout on her arms, along with some quads expanding on her legs. To top it all off, you spotted that Brenda has also grown a 10 pack of abs, making her a completely muscular woman, compared to the strong girls you've seen in the girls wrestling team. You even bet that Brenda could take out a couple of the female wrestlers at your school with her new muscles, but she wasn't done yet.