He's Got A Great Kinetic Energy Chain
Tennis players must have a kaleidoscope of variables to help them achieve greatness. They must have the speed of a sprinter, the endurance of a marathon runner, exceptional balance, the ability to accelerate and decelerate instantly, power and the analytical mind of a chess player.
Today, and maybe in then entire history of tennis, no one is better than Roger Federer.
When you look at Roger Federer, he does not look like the stereotypical athlete. What makes Roger Federer such an amazing athlete? He's not carrying around a ton of bulk. He is 6'1", and weighs 187 pounds. According to exercise physiologist, Jeff Chandler, "He's got a great kinetic energy chain." A kinetic energy chain means the parts of the body act as a system of chain links, whereby the energy or force generated by one link (or part of the body) can be transferred successively to the next link. (Elliott and Saviano, 2001; Elliott & Kilderry, 1983). The body works together as one, from the toes, up trough the legs, core, and out through the hands. Because Federer's body moves as one unit rather than many he can accelerate and decelerate very quickly, he has the body control to change direction almost instantly.
If you are looking for an athlete to emulate it's Roger Federers. His body is lean, but he is in total control of his body and can generate great force. You want to have the kinetic energy chain that he has. This does not come from lifting heavy weights, he trains his body as a whole, not piece by piece. You must train your nervous system as well as your muscles. Just as tennis, or any sport, is multifaceted, his workout is multifaceted.

Comments
so does Manny Pacquiao he probably has one of the best kinetic energy chains in any sport you see how hard he hits