The Court’s Secret:
Why Tennis Extends Life

For many years, Danish cardiologists have been searching for an answer to a simple question: how does leisure time affect life expectancy? The Copenhagen Metropolitan Cardiology Study followed 8,579 residents of the Danish capital for nearly a quarter of a century. Participants included runners, swimmers, cyclists, soccer players, and tennis players, while the control group consisted of city residents who spent little time exercising. The researchers controlled for age, smoking, income, and education separately to avoid attributing the effects of exercise to other people.

The final table surprised even the doctors themselves. Regular tennis players had a 9.7-year longer life expectancy than the sedentary group. Badminton added 6.2 years. Team soccer added 4.7 years, cycling 3.7, swimming 3.4, and jogging 3.2 years. Gym workouts only promised about an extra year and a half.

The mystery isn’t about calories. Cycling and swimming burn more energy per hour than a game on the tennis court, and it was the racket that provided the lifespan boost. The study’s authors offered two explanations: the structure of the game itself and the people around the player. The Danish study relied on questionnaires, and the participants underwent follow-up health checks at a clinic.

Smart cardio on the court

A match is structured as a series of short bursts and pauses. A sprint to the ball takes three to five seconds. A pause. A return to the center, a wait for the serve, and another throw over the 0.914-meter-high net. Over the course of an hour and a half of a match, the heart undergoes hundreds of acceleration and recovery cycles, and the total distance covered is typically three to five kilometers. This type of work resembles interval training, developed for runners and skiers.

The body learns to quickly raise the heart rate and quickly return it to rest, and the vascular walls retain elasticity longer. Beginners benefit from keeping a simple diary: they record how they feel, the duration of their practice sessions, and their tennis scores — game results, set scores, and most successful shots. The numbers show progress more clearly than any sensations and maintain interest in the first few months.

The skeleton benefits from the game. The singles court is 23.77 meters long and 8.23 meters wide, and each point requires forward, backward, and sideways steps. Multidirectional footwork places stress on the bones, which doctors recommend for the prevention of osteoporosis. Balance and flexibility are developed throughout the game, without the need for dedicated mat exercises.

The upper body is also busy. Each serve propels the racket through an arc: the push of the legs, the rotation of the body, the whip of the wrist. Both the forehand and backhand work the core muscles because the power of the shot comes from the hips and lower back, not the arm.

The equipment is modest. The ball weighs about 58 grams and only holds air pressure for a few games, so clubs buy it in boxes. A beginner’s racket weighs about 300 grams without strings. Strings are changed once during the active season, and each amateur has their own stringing ritual.

Speed Chess

The ball crosses the court in less than half a second. During this time, the player evaluates the trajectory, selects the shot, shifts body weight, and finds the point of contact. The brain operates in continuous anticipation mode: peripheral vision catches the opponent’s swing before it even touches the strings, and the legs begin moving before a conscious decision is made.

Physiologists call this type of workload "coordination-intensive": movement, perception, and decision-making are combined in a single action. Observations of elderly racket players link regular games with a slower decline in memory and reaction speed. In decision-making tests, experienced players often show results typical of younger people. Each game is constructed anew, and the brain is presented with fresh challenges instead of memorized routes.

A chess game lasts for hours. The outcome is decided in a split second.

Reaction time can be trained. Physiologists use a simple exercise with a falling ruler, where the palm catches the movement a few centimeters away, to assess the speed of neural processes. Regular players often have better-than-average results.

Doubles play adds a new layer of challenge. The ball flies between two players at once, and the area of responsibility shifts every few seconds. The opponent’s posture and racket position help predict the direction of the shot.

Why is a partner important?

Badminton, which finished second in the Danish standings, shares one feature with tennis: both games require a real person to play against. The researchers themselves attributed the record-breaking lifespan gains to the interactions between partners. Regular meetings reduce chronic stress levels and provide a reason to get out of the house even on a cloudy day. Game plans rarely go awry: a partner is assigned, a court is booked, and the score awaits the next round.

Club life is simple: a schedule, tournament brackets, and tea after the game. Adult groups bring together players of varying ages and skill levels, and classes are scheduled for the evening after work. Finding a partner is easier than you might think: every club always welcomes a fourth player for doubles play.

A singles game is played by two players. This sport is not played alone.

There’s virtually no age limit for the racket. Veteran tournaments hold categories for players over 60, 70, and even 85 years old, and it’s these players who occupy the morning courts. Many came to the club in retirement and have been playing for decades, passing on their grip to their grandchildren.

Families come to the court for generations. Parents sign up their children for morning classes, and then take the adjacent court for the same hour. It’s easier to maintain a common goal when the location and time are the same for the whole family. Beginners’ groups include students and people approaching retirement age. The combined score evens out everyone’s score in a single season.

First steps on the court

Starting as an adult is common. Training is built around three strokes: serve, forehand, and backhand. During the first few months, children practice with soft, low-pressure balls: they fly slower and are more forgiving of technical errors. Full-court play is introduced gradually, starting with a shortened court. After the first few lessons, the instructor usually recommends a trial match with peers to test their strokes on the move.

The warm-up takes ten minutes: joint strengthening, light jogging, and simulated impacts. The session itself lasts 60 to 90 minutes, and two sessions per week are usually enough to achieve noticeable progress over the course of a season. Shoes should have soft soles to absorb shock; running shoes for lateral movements are not suitable.

Your heart rate should be kept at approximately 60-70 percent of your maximum. A practical guideline for beginners is: talking during the game is possible, but singing is difficult. Any sports watch will give you a more accurate reading than how you feel.

The score is initially confusing: 15, 30, 40, game. The logic becomes clear after the first game, played to completion. After a few months, the beginner masters his first full set, and doubles play makes progress even more noticeable: there’s less running around between the two of them, more tactics.

Regular sportswear is fine. Practical items include a waterproof jacket for outdoor courts, a 0.5-liter water bottle, and a sun hat. Instructors recommend bringing extra socks, as shoes get dirty first on clay courts. Indoor courts are open year-round, and outdoor courts open during the warmer months.

Choosing a gym is a simple matter of walking around. Indoor courts are usually adjacent to locker rooms and showers, while outdoor courts offer bleachers and evening light. Beginners find the indoor courts more convenient: weather doesn’t cancel classes, and the schedule isn’t affected by the season.

You can sign up for a trial lesson at most clubs: an instructor will select a racket of the appropriate weight and demonstrate a basic grip, known as the Eastern grip. Then there’s the schedule, the net, and the person across from you.