It charges your legs with jet fighter afterburners and helicopter mobility, your serve becomes a high-caliber ballistic weapon while your groundstrokes fortify your baseline defense. Just ask anyone who's used a specific training program to augment their game, or better yet, ask their opponents. Surprisingly, in this recreational sport's fitness training, power is a special weaponry that's usually under utilized.
Power equals force x velocity.
In application, it's how rapidly an athlete can contract specific muscles to effect movement. His muscles are contracting, fast and fully, to move the loaded bar about 4 feet in a fraction of a second. Another, a skilled martial artist is able to fend off several attackers at once, with instantaneously coordinated action. The Olympic lifter's ability is strength determined, whereas the martial artist's skill is predicated on speed. The rapidly paced conditioning that develops speed is impossible with great load, and is thus best implemented with high velocity exercises.