This is an extract from a recent article in Tennis Life magazine written by Anne Parkhurst, Academy Director for the David Lloyd Leisure Tennis School.

It applies to all of us as we are all striving to improve.  We practice hard and feel our game is improving but yet when our level drops during tournaments we wonder why.  Here are some points that we can all do very easily without any extra effort.

Have you ever watched what the pros do as they change ends or take time between sets?  They always have some fluid and sometimes a cereal bar, a banana or another similar type of snack.
The fluid they take can be just plain water or some sort of energy drink - but it is likely to be both.  A normal tennis match will take over an hour  and research shows after playing for an hour water is not enough to keep the body working at a high level.  Players need to replenish the electrolytes that they have lost in playing so energy drinks are essential.
When taking a drink the pros generally start with some water then some energy drink and they repeat this 4 or 5 times at every change of end, even at the change of ends in the tiebreak.
You will notice that the pros maintain almost the same standard of play at the end of a match as they did at the beginning.  One of the main reasons for this is obviously their level of fitness but being fit won't help you if you become dehydrated and lack energy.  As your energy level drops so does your concentration and that is when mistakes happen.
Assuming club players want to improve, can they learn from the pros?  Are hydration and diet important in tennis?  Does what happens before and after a match matter?  The answer to all these questions is yes?

Eating for Tennis.
The first objective for a player at any level is a balanced diet with regular meals that will give enough fuel for general day to day living, training and matches.
It is important to have regular intake of protein and carbohydrates as well as fats and fibre - the five a day rule is a good one.  You also need to balance your food intake with your exercise output.
Where tennis can be a difficult sport in which to think about diet and getting your energy levels right is that there is no real season.  When you do compete you could play several matches in a day: and you never know how long each match can take, so a daily high quality diet is a basic need.

How to prepare for a hard practice, match or tournament.
One secret of the pros that we can all benefit from is to understand wht and when they eat.  Fuelling up with energy from complex crbohydrates like pasta, cereal and bread before a match is important because of the "slow release" nature of the energy this gives you.
On the day of a match breakfast is important, again to build the energy stores you will need (try to avoid fatty foods because they take a long time to digest).
Make sure you eat three to four hours before you play or practice so that you have time to digest the food.  If you know you have practice or a match after school/work, make sure you have lunch so your energy levels are high.

During the match or practice.
Like what we said earllier make sure you have water and an energy drink and take some regularly, also have either cereal bars or fruit and eat some pieces at a time.  Try to avoid chocolate because this just gives you a quick boost and does not rebuild your energy stores.

After the match or practice.
This is very important to get right.  You should try your best to have some complex carbohydrates and protein very soon after playing.  Both have been proved to be necessary to help your body recover more quickly.  Eating within 30 minutes of playing would be best.

Summary
So to play at your best, make sure you always have a balanced and adequate diet.
Make sure you have complex carbohydrates sometime before you play and that you have small cereal bar type snacks in your bag for a long match.
Make sure you have a protein and carbohydrate meal within an hour of finishing so your body can recover quicker.
Begin hydrating the day before your match.
Always start a match or practice well hydrated.
Take enough water and an energy drink you like on court with you.
Drink a few mouthfuls of fluid each change of end and also between sets.  Do this at regular intervals in practice too.
Rehydrate after practice/match even if you don't feel thirsty.