Martina Navratilova remembers when she started to slow down. “I could tell I was not moving as well as I used to,” said the nine- time Wimbledon singles champion, who played her last match as a professional just before her 50th birthday. “I noticed it when I was in my late 30s. The fast twitch [muscle fibres] just slow down. It’s not much, but you do notice it. It’s frustrating because you feel the same but the results are not the same.”

Decreased speed of movement is just one of the changes that happen to our bodies as they age. While bone strength decreases, body fat is prone to increase and muscle mass drops too. Maximum heart rate and aerobic capacity fall and we become less flexible.

Playing tennis regularly can help delay many of these changes, but reduced strength, speed and flexibility are unavoidable, no matter how often you play. While many senior players enjoy playing recreationally, the likes of John McEnroe, Goran Ivanisevic, Pat Cash and Ivan Lendl compete on the ATP Champions Tour, which came to London’s Royal Albert Hall in December for the final event of the 2014 season.

As well as the former professionals, there is a thriving competitive scene for veterans’ tennis. The British over-40s women are world champions after winning gold at the ITF Seniors World Team Championships in Florida, while William Collins, born in 1929, won the over-85 men’s singles title at the British Seniors’ Grass Court Championships at Aorangi Park in August.

Research shows that tennis can use up to 60% of a veteran’s full physical ability, which means that playing tennis regularly can help to decrease the rate of decline in VO2 max (the rate of oxygen consumption), which occurs with age.

While the physical (not to mention the psychological and social) benefits of tennis are obvious, older players’ hearts work harder than those of younger people. Consequently a veteran who plays competitively must be physically fit to play tennis. They should not be playing tennis in order to become physically fit.

Cross-training such as jogging, cycling and swimming will help increase aerobic fitness levels for tennis, but interval sessions, such as fartlek training or a game of squash or racketball, help simulate the irregular patterns of tennis matchplay.

Research also suggests that physical fatigue does not result from muscle lactate accumulation but from a decrease in the speed of heart rate recovery immediately after a point is played. The anaerobic energy system plays a reduced role in veteran singles, so training that invokes high levels of blood lactate should be avoided. Any interval training should be at a lower intensity and the work-to-rest ratio should be adapted accordingly.

Strength and flexibility training is recommended at all ages, but exercises can help prevent the vast majorities of injuries sustained by veteran players. Common injuries include tennis elbow and ruptures of the rotator cuff (shoulder), as well as generic muscle tears and ligament degeneration.

As well as reducing the risk of injury and increasing strength and mobility, strength and flexibility training can help slow down the rate of bone mineral loss and reduce the risk of arteriosclerosis (hardening of the artery walls). A daily stretching routine combined with resistance training three times a week can help play an important role in preventing injury. Exercises should focus on addressing tennis-specific muscular imbalances as well as improving strength and control of the core shoulders, knees and hips.

As your body ages, it takes longer to repair itself. Bones, muscles, joints and ligaments are not what they used to be, and in the event of an injury it is important to give the body time to recover. However, while the body needs time to heal, rehabilitation will require a balance between adequate rest and the need for active movement to prevent a loss in the range of joint motion that can be exaggerated due to the stiffening of connective tissue with age.

With careful planning, recovery and training, you’ll not only be able to play tennis to stay fit and healthy, but stay fit and healthy to play tennis.