Applying What We Know About Copoly

In the first article in this series on strings and spin, we learned that slippery strings, like copoly, generate extra spin because the main strings slide, stretch and snapback, applying an extra spin-boosting torque on the ball. (Click Here.) In the second article, we saw how copoly strings are actually similar to their ancestor from the 1970s, spaghetti strings. Both technologies use the same sliding and snapback mechanism to give players more spin. (Click Here.) But what does this mean for you? In this third article, let's go over some of the ways copoly strings are used in pro tennis, see what the applications are at other levels, then suggest a few new ground rules for equipment selection and care. It's important to emphasize at the start that the most important factors for spin generation remain racket head speed and swing angle. To generate more spin, the most important thing to address is technique. On some balls, pro players tilt the racket head forward a few degrees. "If you want more spin the first thing you need to do is hit the ball harder," says tennis physicist Rod Cross. "The second thing is to hit at a steeper angle. "The...