Comfort and Power Zones
In the never ending quest to develop better players, coaches need to help players increase the range of their comfort and power zones. Comfort zones describe the range of height where a player can return a shot with confidence.
Power zones are the range where a player can add velocity and/or topspin to an incoming ball. If you increase the range of your comfort zone the range of your power zone will also get bigger.
In prehistoric times, players used wood racquets with strings that were initially gut, but later a variety of materials. The rackets and strings had limited spin and power potential compared to today.
On grass, hard courts and indoor carpet, most balls at or above chest height were low velocity balls. The ball bounced higher on clay than these surfaces, but shots did not have close to the same velocity or spin rates they do today.