YBCA

I know strength and conditioning starts right from the beginning stages of learning the game with the warm up sessions. But then i want to know at which age should you start focusing more on strength and conditioning?

In Secret of Soviet Sports Fitness & Training by Dr. Michael Yessis, he writes:

A large body of Soviet anatomical/physiological evidence now shows that prepubescent childre can safely lift weights – and so they do. From ages nine to thirteen, Soviet children demonstrating potential in weight training begin a general conditioning program with light weights that eventually leads them into specialized routines. The research has examined everything from growth-related epiphyseal disks to heart-circulatory function and has shown that, rather than causing injuries, the Soviet approach produces better athletes.