Perhaps you’ve seen those colorful foam balls that many tennis instructors use with kids and beginners. These are often called “transition balls” because their purpose is to help novices quickly become better at rallying. But they can help better players of any age increase their racquet-head speed, which is critical to generating power. The idea is simple: Because the foam balls are larger than regular tennis balls, they travel more slowly and cover less distance. This allows you to swing faster and with more abandon without fear of hitting the ball long. After going back to regular balls following a session of using foam balls, you should find your ground strokes landing deeper and with more pace.

Jeff Hawes, USPTA Master Pro, Alamance Country Club, Burlington, N.C.