Swimming is a easy activity to get more muscle mass. Also running, such as track or cross country.
leg exercises
Exercise will help your muscles get stronger, but strong muscles do not neccessarily have to be large.
Your muscles are growing to make you strong and you've been working them hard
it keeps the muscles strong becuase they and allways being used if you exercise and the joints and flexible because they and always being moved about
eat right, exercise
Eat healthy, exercise, and build your muscles
When exercise is done the muscles are broken down. The muscles are then repared back stronger.
no, they were developed by exercise therefore it isn't a genetic trait.
Exercise
You exercise daily.
yes
its can give you strong heart :) and give you a lot of energry hahaah
yes they can make you strong but only in the stomach not in the muscles