Originally Posted by dangalak
I never understood why people said that tennis requires you to be tall. I mean why? You know that height isn't synonymous to power, right? Nishikori hits hard enough.
But it is. There's a simple reason why tall guys like Del Potro, Berdych, Soderling, Rosol, etc. can hit their groundstrokes so hard. They can generate more torque with the same swing. Torque = Force x Distance. So with the same amount of force on their swing, they can generate more torque because their arms are longer so they hit the ball further away from where the force is applied (shoulder).
And of course, no one is going to argue that all else being equal, taller players can hit their serves bigger than shorter players can due to leverage and angle (and net height).