The article is long and comprehensive, so you can use the table of contents to go straight to the section you want.
The article is contributed by Petri Jalanko, M.Sc., Ph.D., exercise physiologist and, PhD researcher, from the Helsinki Clinic for Sports and Exercise Medicine.
- Tennis as a Sport
- Tennis Sport Analysis
- Fitness Testing In Tennis
- Who Can Go for Fitness Testing?
- Fitness Testing Price
- FAQ
- Read More
Tennis as a Sport
Tennis is a demanding sport that requires players to have skills in four key areas: tactical, technical, physical, and mental. Like many racket sports, tennis requires excellence in each area. This is greatly influenced by the fact that tennis is an individual sport, with short points and long matches.
Technically, tennis requires extreme concentration, as the contact time between racket and ball is between 0.003 and 0.006 seconds. Even a slight mismatch in timing can significantly impact the shot’s success.
Anareobic = Fast performances where oxygen is not needed, such as sprints.
Aerobic = Oxygen-assisted energy production for athelic performance.
The physical nature of a tennis match consists of varied anaerobic performances and several rest periods spread over a long period of time. As tennis involves several rest periods, the player’s body is able to recover through aerobic energy systems.
Type 1 muscle cells (slow twitch) = Contract slower but, endure longer –> better endurance.
Type 2 muscle cells (fast twitch) = Contract faster, but fatigue gaster –> better power production.
Type 1 muscle cells (slow twitch) = contract slower, but endure longer –> better endurance
Type 2 muscle cells (fast twitch) = contract faster, but fatigue faster –> better power production
Tennis combines fast power and endurance, requiring both type 1 and type 2 muscle cells. Tennis is also a more muscularly challenging sport such as weightlifting, which requires more type 1 muscle cells, or endurance running, which requires more type 2 muscle cells.
Although both muscle cell types are required in tennis, studies have found that the dominant muscle cell types of players vary between type 1 and type 2. This means that some players can be very fast and some can be very durable.
Because of the different physical characteristics such as muscle types, it is good for tennis players to know what their own physique is made of. Knowing your own physique will help you to build customized and effective training and recovery programs to make your training and playing more effective and safer.
Fatigue and Injuries
One of the biggest factors hindering tennis performance is fatigue. Studies have shown that fatigue can reduce a player’s accuracy by up to 81%, which is why one of tennis’s most important training goals is to prevent and manage fatigue.
In addition to fatigue, overtraining is one of the biggest contributors to injury. Repetitive strain injuries (RSI) are the most common type of injury in tennis and are largely caused by repetitive and rapid movements such as serving. Tennis is constantly evolving into a faster form, where players’ bodies are put under greater strain. As a result, players will be more prone to various training and playing-related injuries.
Kinetic Chain
Kinetic chain = The synergy of muscles and joints, where kinetic energy is transferred from one part of the body to another. For example, in tennis, power is generated in the legs, transferred through the core to the shoulder, and then to the arm.
In terms of physiology and power production, tennis is very similar to other sports played on the ground. The player’s power production consists of a kinetic chain, where the player creates tension in the body through the legs, which he transfers through the middle body to the shoulder and from there to the arms.
In tennis, the core muscles play a vital role, linking the legs and arms. They hold, generate, transfer, and absorb the player’s energy
In tennis, the forehand and backhand strokes are made through a lateral rotation of the body, with the abdominal muscles providing power and balance. Weak or asymmetrical abdominal muscles can reduce the power and accuracy of strokes because they do not provide sufficient support. Poor support leads to an uneven stroke position, which results in a poorer stroke.
Ideally, top players have strength-symmetric abdominal muscles that allow them to control their bodies and shots with precision.
Tennis Sport Analysis
This section lists the physical characteristics typical of tennis players.
Fat Percentage and Oxygen Capacity (VO2Max)
The majority of tennis players have a lower-than-average body fat percentage and a higher maximum oxygen capacity compared to the general population. Top players have oxygenation capacities ranging from 44 mL/kg/min to 69 mL/kg/min.
Although tennis requires more anaerobic capacity, tennis players have been found to have similar physical and body composition characteristics to endurance athletes. However, this does not mean that tennis players should train in the same way as endurance athletes.
It is important that top tennis players have a high maximal oxygen uptake (>50 mL/kg/min), but very high oxygen uptake (>65 mL/kg/min) has not been shown to be of significant benefit in a match. However, high oxygen uptake can be beneficial for match recovery and during long tournaments.
Therefore, the time used for extra endurance training can be better used for other physical, psychological, technical, or tactical training.
Heart Rate
The average heart rate of a competitive player during a game is about 144.6 beats per minute. During the game, the player’s heart rate is about 86% of their maximum heart rate and during breaks, it is 82.9%.
Lactic Acids and Lactates
The modern understanding is that lactic acid is not produced in muscles during high-intensity exercise, but instead, lactate is produced in muscles. Lactate is the antidote to the regulation of muscle acidity and its formation is a good thing, especially when the capacity of the muscle for acidic cellular respiration is exceeded.
Through chemical reactions, lactate formation reduces muscle acidity rather than increasing it. This is why lactate production is very important for the continuation of high-intensity sports (Hulmi 2024).
Lactate is an important molecule in cellular energy metabolism and even as a messenger molecule, so lactate is basically a good guy rather than a bad guy – Juha Hulmi, 2024
However, tennis players do not suffer as much from muscle acidification as other athletes, as they have several breaks during the game to allow muscle acid levels to equalize.
In favor of performance-oriented training, it is important to keep the acidity levels of the players’ muscles low, as high acidity levels impair technical development. Tennis matches usually consist of short points lasting around 2-10 seconds.
During short points, the players’ muscle acidity levels do not have time to reach very high levels, so tennis training should reflect similar conditions.
Energy Systems and Metabolism
Developing quality training and competition programs requires a good understanding of the player’s energy system and metabolism. The right energy systems need to be used in training to build up the endurance of the player.
Types of Players and Work-to-Rest Ratios
Tennis matches can last anywhere from one to five hours. However, the average best-of-three tennis match lasts around 1.5 hours and the average point lasts around 2-10 seconds. In addition, research shows that the playing styles of players have a significant impact on the duration of points and games.
- With the aggressive player controlling the game, the points lasted about 4 seconds
- When an all-court player controlled the game, the points lasted about 7 seconds.
- When a backcourt player controlled the game, the points lasted about 13 seconds.
The work-to-rest ratio is generally between 1:3 and 1:5, so players have more time to rest in relation to their physical effort. However, this is significantly affected by the different types of courts, as fast courts such as hard courts have shorter points while soft courts such as clay courts have longer points.
As the amount of work in tennis is favorable to rest, this should be taken into account when planning training and exercise programs. It would also be important to simulate playing conditions by ensuring appropriate rest periods.
Hydration
Most of the top tennis matches are played in warm climates, except in the Nordic countries. Because of the warm climate, proper hydration is a critical part of preparing for a tennis match, as under-hydration puts players at risk of injury and heat-related illnesses such as heat stroke.
College tennis = the lowest professional tier of tennis
Studies have shown that tennis players can sweat more than 2.5 liters per hour, which poses practical and physiological challenges. For example, if players drink more than 1.25 liters of fluids per hour they may experience digestive discomfort while playing so it is important to find the correct balance.
The average university tennis player drinks about one liter of fluids per hour during a game.
However, proper hydration is difficult, as it is not enough for a player to just drink when they feel thirsty. The body can lose 1.5 liters of fluid before thirst is experienced. By this time, the body’s thermoregulation is already impaired and performance levels have started to deteriorate.
Even a small 2% underhydration relative to body weight will reduce physical performance. A 5% under hydration can reduce performance by up to 30%.
Type and Amount of The Fluid
During a tennis match, it is important that the player hydrates himself with the right kind of fluid. According to many researchers, a carbohydrate-based electrolyte drink would be a better hydrator than water alone.
Compared to water, carbohydrate drinks contain substances that improve the absorption of fluid into the internal organs. In addition, carbohydrate drinks often contain glucose, or fruit sugar, which also improves fluid movement in the body.
Each player has an individual sweating rate and hydration needs. For example, if a player sweats at 2 liters per hour, he should drink 0.25 liters (2.5 quarts) at each changeover, assuming five changeovers per hour. This would be enough for the player to recover 62.5% of the fluid he sweats every hour.
It is recommended that players drink 200ml (2 quarts) every 15 minutes to maintain a good fluid balance (in warm conditions). In even hotter temperatures, above 27 Celsius (80 °F), it is recommended that the player should drink at least 1 liter of fluid per hour, which is about half the amount of fluid lost by the body through sweating.
Each player should find out their own hydration levels, but if this is not possible then the recommendation in warm conditions is to drink around 400ml (4 cups) every 15 minutes. The 400ml is chosen as it is slightly higher than the rate of gastric emptying, which will reduce dehydration in hot and humid conditions.
Summary of Physiology
- Fatigue is one of the biggest limiting factors in tennis, and can reduce shot accuracy by up to 81%.
- A good competitive tennis player’s fat percentage is less than 12% for men and less than 23% for women.
- A good maximum oxygen capacity is above 50 mL/kg/min for men and 42 mL/kg/min for women.
- Physical training for tennis should be based on sport analysis and the individual characteristics of the player. Some players should also focus on aerobic fitness.
- A tennis player can sweat more than 2.5 liters per hour, so at least 1.2 liters (12 quarts) of fluids should be consumed during the match to avoid dehydration.
- It is advisable to drink at least 200 milliliters (2 quarts) of fluids during the changeovers.
- In hotter climates (above 27 degrees Celsius/ 80 °F ), players should drink at least 400 milliliters (4 quarts) of changeovers.
- Attacking players play shorter points, so their workouts should include more short drills that focus on anaerobic fitness, speed, and strength.
- More defensive players play longer points, so their workouts should focus more on building muscular endurance.
- The work-to-rest ratio in a tennis match is 1:3 to 1:5.
Fitness Testing In Tennis
The next section explains what is tested and why.
How Does Fitness Testing Work?
Tennis, by its nature, requires speed, agility, and strength combined with a medium-high level of aerobic and anaerobic fitness. It is therefore important for the player to understand the different performance levels of his/her body in order to develop them in the optimal direction.
Fitness testing should be part of a player’s regular training and should therefore be done either every three months or twice a year. Regular testing will allow better monitoring of the player’s development and response to load levels.
The Helsinki Sports Medical Centre (Hula) recommends a direct maximum test with thresholds or an indirect maximum test with lactate thresholds while running for the competitive tennis player.
Oxygen Capacity
An essential part of fitness testing is measuring (maximum) oxygenation capacity. An oxygen capacity test measures respiratory gases and the body’s ability to transport oxygen from the breath to the muscles and use it for energy production.
The measurement of oxygen capacity can be used to determine a player’s endurance performance thresholds (aerobic and anaerobic thresholds) and the appropriate training focus areas. For tennis players, the measurement is usually done by running.
Blood Tests
In more comprehensive fitness tests, a blood test can measure a player’s lactate levels and determine the player’s lactate threshold, the level of stress at which lactate starts to build up. The lactate threshold allows the player to set the right load level for training so that he does not overtrain.
Strength
A fitness test can measure power production and identify the player’s strengths and weaknesses. Identifying weaknesses and strengths can be used as a starting point to either develop weaknesses or improve strengths. This decision is usually made in discussion with the player or coach.
In addition to weaknesses and strengths, we can compare a player’s strength benchmarks and see how they compare to the overall benchmarks for the sport.
The strength tests also test the half differences, especially in the muscles of the lower body. If one side is clearly weaker than the other, it puts the player at risk of injury and weakens performance. After identifying the half differences, the player will be instructed by fitness testing on how to equalize the differences.
Endurance and Fitness
A fitness test can measure a player’s aerobic and anaerobic endurance. The endurance measurement can be used to determine the heart rate intervals at which the player should train. By training at the right heart rate, a player will be able to train more often and more efficiently as they will not overload themselves and will recover faster.
Mobility
The fitness test can also measure the directions of movement and note the half-differences between them.
Speed
Fitness testing can also measure a player’s speed and how quickly they can accelerate or change direction when running.
Benefits of Fitness Testing
- Players discover their own weaknesses and strengths
- The player can compare his fitness to the requirements of the sport
- Optimal heart rate levels for training
- The fitness test helps to monitor the development of the player and the effectiveness of the training
- The fitness test is used as a coaching tool and helps to find the optimal training level
- Fitness testing helps to develop endurance fitness
- Recovery is enhanced when the player knows the correct heart rate zones
- Gives the player an idea of his own strength levels and power conditioning
- A better understanding of your own physiology prevents injuries.
Who Can Go for Fitness Testing?
Almost anyone from a child (10 years) to a senior can go for a fitness test. You don’t have to be a top athlete, as even a basic player can get a useful insight into their health. Competitive athletes can opt for a more comprehensive test, which goes into more detail about their physiology.
Basic athletes can choose a more general test, which tests the basics such as body control, mobility, and body composition.
Fitness Testing Price
Depending on the scope of the tests, the price of fitness tests varies between $22 and $550. For example, a maximal oxygen capacity test costs around $385, while basic threshold tests cost around $110
FAQ
Can your child go for a fitness test
— Yes, children from the age of 10 upwards can test their basic fitness.
How should I prepare for a fitness test?
— You do not need to prepare for a fitness test, but you should avoid heavy physical activity for the first couple of days.
How can you test your own fitness?
— You can generally test your own fitness with tools such as a sports watch or heart rate monitor. These devices provide reasonable reference values, but fitness testing gives athletes more accurate and reliable results.
What is the best way to measure your heart rate in sports?
— A chest-strapped heart rate monitor is the most accurate device compared to a sports watch or a ring.
Read More
Lihastohtori — Lactate acids (in Finnish but can be translated by Google)
International Tennis Federation Guidelines for Fitness Testing