Is tennis an aerobic or anaerobic sport?

Tennis is mainly an aerobic sport because of the length of the rest between games and sets. However, training only the aerobic system is problematic when players have to do a series of sprints in a point and need to tap into their anaerobic system. If the player has not trained this anaerobic system, they will start to fatigue quickly.  This means that tennis is an aerobic sport, but performance is limted by response to anaerobic demands. Ultimately, you will need to train so you have a good aerobic base and doing high-intensity intervals to raise the anaerobic threshold will help during match performance. Additional long distance runs are not typically needed since the intensity and length of practices should provide the aerobic work capacity for which the long runs were meant. You will need at add short sprint training at a high anaerobic level a couple times per week to make sure the anaerobic sytem is ready for any demands the match might bring.