Obtain advice from people who are experienced in exercise. If you can get to a gym, using their cycles, rowers or steppers are all aerobic exercises along with the classes, both circuit and aerobic. Muscular conditioning is done through exercises against resistance. This can make you tennis serves and strokes more powerful, and assist in other ways like injury prevention. Try to do some exercise every day.
Any activity is better than no activity.
Playing games other than tennis can allow you to get fitter without putting the same stress on your body the same way as playing tennis all the time. Doing some light exercise helps the body recover from your exercise and may reduce injuries. After cooling down it is very important to do some stretches, to lengthen out all those tight muscles that you have used in your workout. The sort of stretches done are similar to those done after the warm-up. Apart from aerobic and muscular work there are two more types of training that you need to do to improve your tennis skills.