How Old Do You Have To Be To The World Gym How In The World Does A 12 Year Old Have Muscles?

How in the world does a 12 year old have muscles? - how old do you have to be to the world gym

It's a boy in my class at school, we all just our final grade, so now we are children school.This is certainly the kind of sport, run very fast, good in the shot put, javelin and the disc, it looks good in every kind of sport! If you are a sleeveless shirt, you can see the muscles in his arms! Its bigger than my father too, and this boy is not thirteen did not! To look old for her age, even if, as a sports day with around 15 or 16.Its him playing basketball every day after school.But sport and physical education, I do not see how a year. They believe it is part of a gym or something? We can not make a 12-year sentence after Malaysia squats and push-ups everyday.So answers ...?? PLS