Characteristics of the Sport
Tennis is a game of skill, speed, agility, concentration and often endurance. It is played by both men and women, in singles and doubles competition (same-sex and mixed-sex pairs). Matches are played indoors or outdoors, on a range of different surfaces, including grass, clay and hard court.
A game of tennis is characterised by multiple high intensity efforts interspersed with variable periods of recovery. The International Tennis Federation (ITF) has established maximum rest times of 20 seconds between points, 90 seconds between changeovers and 120 seconds between sets. The length of points, and indeed matches, are highly variable and will depend on a range of factors including the court surface, as well as the playing styles of the athletes e.g. serve volleyer as opposed to baseliner. Matches can last upwards of three hours for women and four to five hours for men. The game is highly reliant on anaerobic energy systems, although a developed aerobic capacity is an advantage in terms of recovery between points, stamina and tolerance to heat.
Due to a hectic competition schedule, which can run from early January until late November, tennis players will typically only have a very short off-season (2-3 weeks), though they will usually incorporate recovery/easy weeks between tournaments during the year.
During the non competition phase, athletes train between 20 and 25 hours per week. Training time is divided between on-court practice as well as off-court conditioning. The latter may include resistance training to develop strength and explosive power, plyometrics, dynamic/ballastic weight training, core stability work, as well as interval running training to mimic the work to rest ratios encountered during matches. The off-court programs are tailored to enhance specific components of the players game and/or work on their perceived weaknesses.
As the season approaches, an increasing proportion of the athletes training will be dedicated towards on-court work, though they will still continue with some off-court training during the early part of the season.
A tennis match is played over the best of three or five sets for men, and the best of three sets for women. The length of a match varies greatly, from 30 minutes to three hours for a three-set match and from 80 minutes to more than five hours for five-set matches. The fuel and fluid demands of a match will vary accordingly.
The playing schedule of athletes will depend on the size of the tournament and whether they will be playing doubles in addition to their singles commitments. Grand Slam tournaments (four held during a calendar year) are played over a two week period, with the title being won over seven matches. Players compete every second day, or sometimes every day in the case of rain delays, to progress to the final. Most other tournaments are played over a 7-10 day period and will generally require daily match play, or even two matches a day if the player enters the singles and doubles draw. If “knocked out” early in a tournament, players will often continue to undertake hard on-court training to mimic the demands of match play, especially during the early part of the season.
On average, an elite player participates in twenty tournaments each year. While muscle glycogen levels may survive one match, the continual daily schedule will challenge the athlete to fully recover stores between matches. Depleted muscle glycogen levels will interfere with both sprint and endurance components of performance, and limit the player's ability to perform at an optimum level.
Having long arms and a relatively low centre of gravity (short legs in proportion to trunk) can facilitate extra reach for playing strokes, greater height for serving and greater mobility around the court. However, tennis players come in all shapes and sizes. Players adapt their game to make the most of their physical strengths. For example, tall, muscular players might use their height and power with an aggressive serve and volley game, while shorter, agile players may do better with a mobile, court-covering game. In general, high levels of muscle mass and low body fat levels afford competitive advantage in terms of greater power behind shots, as well as greater speed and agility around the court.
Common Nutrition Issues
Players at the AIS train 6 days a week, often two to three times a day, both on-court and in the gym. To ensure optimal performance in and adaptations from each of these sessions, they are encouraged to consume nutrient-dense carbohydrate foods at all main meals (e.g. cereal, pasta), along with strategic intake of carbohydrate-rich food/fluids either during or immediately after training to facilitate the recovery process. The latter is especially important when the time between each session is limited. The addition of protein to this snack (e.g. tub of yoghurt) will further promote the adaptive and repair processes. The volume and type of food/fluids used during and after training should reflect the players dietary and physique goals.
Players will likely finish each match in fluid deficit, with lowered levels of muscle and liver glycogen, as well as with some degree of muscle damage or breakdown, the extent of which will depend on the duration and intensity of the match, as well the environmental conditions. Players must therefore adopt appropriate nutritional strategies to promote adequate re-fuelling, re-hydration and repair to allow them to compete at their best for their next match. The uncertainty of starting times, match durations, along with the often “foreign” food environment can make meeting these goals a challenge.
Fluid and electrolyte replacement
Being a summer sport, tennis is often played in very hot and/or humid conditions, meaning issues relating to hydration and heat stress will be of concern. The few studies that have measured sweat losses during tournament or simulated match play have noted losses of between 1.0-2.5 L, which serves only to reflect the large variability in the sweat response between individuals. That said, when players are involved in matches lasting longer than two hours, particularly those noted to be “heavy sweaters”, they will likely amass large sweat and sodium losses. This can also be true for matches played indoors, due to the lack of airflow to promote evaporative cooling.
It is important that players implement strategies to ensure they start matches well hydrated, minimise fluid deficit during, and promote rapid re-hydration after matches. At the AIS, players are encouraged to monitor their hydration status each day of the tournament (see Fluid – who needs it? and Sweat under the ‘Hydration’ section) and drink to a plan based on typical sweat rates incurred during training. After matches, they are encouraged to drink volumes of fluid in excess of their existing fluid deficit to account for ongoing sweat and urine losses. When fluid losses have been substantial, players are encouraged to consume fluids with recovery meals/snacks and/or consume sodium containing fluids to not only account for sodium losses, but to also allow for better retention of the fluids consumed.
Incidences of muscle cramps, though not widespread, have been well documented during tournaments. While excess fluid and/or sodium losses have been implicated in the etiology of these, the evidence for this is still inconclusive. That said, players still need to be encouraged to be proactive in their replacement of fluid and electrolyte losses during and after matches to counter the negative impact dehydration can have on performance.
Carbohydrate intake during matches
While carbohydrate intake during matches can provide an additional fuel for the muscles and central nervous system, the uncertainty of the length of matches makes it difficult to plan an appropriate intake. Anecdotal evidence suggests that many players will wait until they start to feel fatigued before they have any carbohydrate containing food or fluid. Often they will leave this too late, at a point where the ingested carbohydrate will not have time to get to the working muscles to have any beneficial effect.
A useful strategy for players is to target an intake of 20-50g of carbohydrate each hour of play (depending on their energy budget/dietary goals and extent of re-fuelling from previous matches), rather than waiting until the point where they are already fatigued. Sports drinks provide the opportunity for players to meet their fuel and fluid requirements simultaneously. Other suitable options may include plain sandwiches, pretzels, bananas and sports gels/bars.
Re-fuelling and repair
To promote adequate recovery of glycogen stores, players are encouraged to consume a carbohydrate-rich snack or meal within the first 30 minutes of completing training or a match. The type and volume of food/fluids that are suitable will depend on available recovery time (which can range from 1 to 48 hours) and the players other dietary goals. Snacks that provide between 0.5-1.0 g of carbohydrate per kg of body weight and 10-20 g of protein serve as a useful target. Nutrient dense options (e.g. yoghurt), that also help players meet other nutrient goals, are especially useful for those players with a low energy budget. Where tournament venues do not offer suitable recovery snack/meal alternatives, players are encouraged to bring their own supplies (e.g. can of creamed rice, liquid meal supplement), to ensure their needs are met.
Life on the Circuit
Elite tennis players can look forward to a life of travelling - around Australia and around the world. While this can be exciting, it can also be stressful. It is often hard to meet nutritional needs in unfamiliar surroundings, especially when time and finances are limited. Unusual foods, different standards of food hygiene, limited food availability and interference with usual routines can see athletes either gaining weight or failing to meet their nutritional requirements. The following tips may help:
• Being clear about their nutritional goals and staying committed to them while travelling.
• Planning accommodation with meals in mind. Organising an apartment with cooking facilities gives the athlete more control over meals and can keep food costs down. Where this is not possible, making sure the accommodation is conveniently located near suitable restaurants.
• Taking a supply of snacks or food that they are used to having in their home environment. For example, breakfast cereal, dried biscuits, crackers or rice cakes, cereal bars, especially where food availability is limited.
See the fact sheets under the ‘Travel’ section for further information.
This fact sheet is based on AIS / National team athletes and is therefore specific to these athletes. Written by AIS Sports Nutrition, last updated June 2009. © Australian Sports Commission.