30+ YEARS OF EXPERIENCE FROM TENNIS ON- AND OFF COURT
The basics to become an athlete no matter the sport is athletic performance. The foundation is to develop strength and the energy systems. Therefore I recommend that you test your basic abilities to be able to design the training program correctly. For example start with:
1. Energy Systems (Aerob and Anaerob Capacity)
2. Strength (Upper and Lower Body Tests)
3. Power (Jumping Ability)
In the end we need to evaluate the on-court performance. With heart-rate monitoring, serve radar (speed) and timing gates (movement) assessment is performed individually. In addition analyzing the mechanics with Dartfish is very often helpful for the players and for you as a coach.