Host Nykeem doubles up with Chloe, a passionate young tennis player working to perfect her top spin. In the Sports Lab, Dr. Heather explains the aerodynamics of tennis; when a ball is spinning, air pressure forces change its flight path. This is called the Magnus effect, named for Gustav Magnus who was studying the flight of cannon balls. With tips from guest pro Daniel, Chloe is confident about her tennis future. Tennis began in a 12th Century French monastery, and by the 1950's it had moved outside to become lawn tennis. Clay court surfaces have more friction than hard surface courts, so players must adapt their techniques to suit the court.