The Dangers of Dehydration

Dehydration is a dangerous thing, and can cause any number of unpleasant symptoms, and in extreme cases, death.

The human body can last for three weeks without food but only three days without water.

During a competitive tennis match, players can lose up 3 liters of water an hour through sweat. Sweating is your body’s way of lowering your temperature and cooling your skin and through sweating your body not only loses water, but also sodium which is an essential ingredient in your bodies cooling mechanism.

Given that tennis is usually played in a warm environment it is necessary to understand hydration in order to enhance your performance on the court.

If a car runs out of gas, it stops. Your body is the same, inadequately hydrated the main functions of your body shut down, ultimately stopping your body and making it imperative that you ingest plenty of fluids in order to maintain your body temperature.

It has been clinically proven that a loss of 5% of water from your body can impair athletic performance by 30%, and just because you do not feel thirsty does not mean that you are not dehydrated, as your body can sustain a loss of 1.5 liters of water before you start to feel the sensation of thirst.

Despite all of this it is important to regulate your intake of fluids directly before a match as drinking too much too quickly can induce stomach cramps and give you an uncomfortable sickly sensation during the match. Prior to the match you should drink enough liquids that your urine is a light or pale yellow color and during the match you should take in fluids at every changeover.

What should you drink? It is generally accepted that sports drinks, such as Gatorade, are preferable to drinking plain water as sports drinks contain electrolytes and carbohydrates, and are proven to replace sodium levels that are depleted through sweating. Carbohydrates attach directly to your muscles and it they have been proven to help tennis players maintain power and accuracy, even during a long match. Ideally you should have at least 2 liters of water or sports drink courtside.

Avoid all drinks containing caffeine as they have no hydration qualities at all, drinks like tea, coffee and cola drain your body and offer no nutritional benefits. If you have to drink caffeine, do not drink it within two hours of a match, both before or after, as after a match your body needs more water to replenish the fluids lost, and caffeine based drinks do more harm than good.

If at any time during a game you feel light headed, a headache of blurred vision, this is a sign that you are dehydrated and you should take a drink as soon as possible, sipping the water so as not to induce cramps. Different people have different hydration needs, genetics, fitness levels, age and gender can all affect how much you sweat, so it is important for you to be aware of your own needs.

Over time you will be able to judge your body’s requirements and adjust them accordingly, the easiest way of doing so is by weighing yourself before and after a match. If you notice weight loss directly after a match you have not taken in enough fluids and should drink to replenish your levels. Another way is to monitor how frequently you urinate, if you urinate on average every 3 to 5 hours and your urine is alight color the chances are that you are not dehydrated, if your urine is dark and you rarely need to urinate then you are dehydrated and need to up your liquid intake.

Basic Nutrition for Tennis

Everything you eat or drink contains nutrients which your body needs to keep you healthy. Understanding nutrition will help you to keep healthy, allowing you to consistently perform at a high level and enabling your body to recover more quickly. You don’t need to be a nutritionist but you should have a basic idea of how the food you put into your body helps you to optimize your performance and why some foods should be avoided at all costs.

All types of food contain a combination of:

• Carbohydrates

• Fats

• Protein

• Dietary Fiber

• Minerals

• Vitamins

Here I will give a brief explanation of what these components are and how they will benefit you as a tennis player.

Protein

When protein enters your body it is broken down into amino acids used in the production of muscle, haemoglobin (the part of your red blood cells used to transport  oxygen from the lungs to the rest of your body) etc. There are two different types of protein: Animal and vegetable. Animal proteins come from the consumption of fish, meat and dairy product and the vegetable proteins enter your body through the ingestion of nuts, cereals and vegetables. You should monitor your protein intake as excess protein is stored in your body as fat, and will hamper athletic performance. Typically, tennis players should ingest 1.2-1.4 grams of protein per kg of body weight per day.

An example of foods high in protein is:  chicken, fish, pork, eggs, yoghurt, cheese, most beans and nuts.

Carbohydrates

Carbohydrates form the most important part of a tennis player’s diet because they provide the muscles with fuel and help you to avoid fatigue. There are two different main types of carbohydrate: complex and simple. Complex carbohydrates are found in bread, cereals, pasta, rice and potatoes and simple carbohydrates are those found in sugar, sweets and cakes. Carbohydrates should form part of your pre-match meal, and you should increase your carbohydrate intake up to two days before a match to ensure that your levels of glycerol are high ( like running a car- if the tank is empty the car stops). You should also eat carbohydrates within a couple of hours of finishing a match to bring your glycerol levels back up. Ideally a tennis player should eat 4-5 grams of carbohydrate per kg of body weight per day.

Some foods high in carbohydrates are: fruit, bread, pasta, beans, potatoes, rice, soft drinks and bran.

Fat

Fat is a very important nutrient but you should be careful about how much fat you ingest as it can diminish your performance. There are two different types of fat: saturated and unsaturated. Saturated fats are animal fats whereas unsaturated or polyunsaturated fats are vegetable fats. A way to avoid eating saturated fats is by steering clear of fried, greasy foods, fast food, cream, pastry, crisps and chocolates. If you have to, try to have fast food once a week at most.

Vitamins

Vitamins are chemicals that the body needs in small amounts and each performs individual functions within our systems. There are more than 10 different types of vitamins and by eating a varied diet you will ingest them all. Some of the types of vitamins you should be looking for are: A, B1 B2, C, D, E and K. Deficiencies in specific vitamins can result in diseases, for example a deficiency in vitamin A can cause night blindness.

All foods contain vitamins, and eating a varied and healthy diet you will intake all of the vitamins that you need.

Minerals

These are essential for life and are important components in haemoglobin, your hormones and enzymes. They also play an important role in connecting tissue. Important minerals that should be included in your diet are: calcium, magnesium, copper, iron, zinc, sodium and potassium. Your mineral intake should be carefully monitored as some may be hazardous if consumed in large amounts, as the toxins can accumulate inside your body. The following list indicates some of the foods you should be eating in order to maintain your mineral levels.

• Iron: red meat, eggs, tuna and salmon, as well as leafy greens such as spinach and broccoli, dried fruits, oats and lentils are all excellent sources of iron, which is absorbed into the blood and repairs red blood cells, thus increasing the oxygen flow around your body.

• Sodium (salt): soups, gravy, white bread, pizzas, cured meat, potato chips and whole milk. While some sodium is necessary for a balanced diet, too much can be dangerous and it is necessary to regulate your sodium intake.

• Calcium: Milk, cottage cheese, tofu, nuts, oily fish, bread, cabbage and broccoli. Calcium is a mineral essential for the development of strong, healthy bones.

• Potassium: People who exercise regularly and sweat heavily have greater potassium needs as your body loses potassium through sweating. Foods high in potassium are: all meats, poultry, fish and fresh fruits and vegetables.

• Magnesium: Is essential and helps the body maintain normal muscle and nerve function and supports your immune system. Foods high in magnesium are: brown rice, artichokes, tuna, nuts and beans.

• Copper: Copper helps your body in a number of ways, amongst other things it helps your body use iron, maintains bone health and keeps your thyroid gland functioning normally. Some of the foods high in copper are: spinach, sesame seeds, asparagus, eggplants, cashew nuts, tomatoes, potatoes and green beans.

• Zinc: Zinc plays an important role in brain function and wound healing, and helps in the function of your immune function. Some of the foods containing high levels of zinc are: oysters, wheat germ, chocolate, lamb and peanuts.

Dietary Fiber

Dietary fiber is essential in the maintenance and correct functioning of the gut and aids in the absorption of minerals. If you do not have enough fiber in your diet it can lead to constipation, gallstones and diabetes.  High fiber foods include: apples, bananas, oranges, whole-wheat spaghetti, brown rice and bread, beans, nuts, carrots, potatoes and green vegetables.

Maintaining Water Levels in your Body.

Water is the most important thing that you can put into your body and aside from its hydrating qualities performs other functions such as:

• Water protects our organs.

• It transports nutrients around our body to where they are needed.

• Lowers blood pressure and cholesterol.

• Washes waste and toxins from our organs.

Water is also found in some of the foods that you eat, and as you can lose up to three liters of water an hour during a high intensity tennis match, it is imperative that you drink a good amount of water every day. Water also contains some of the minerals that are necessary to keep your body in tip top condition.