Eat right

Carbohydrates Give all the cells in your body the energy they need. For energy that you'll use right away, your body takes those carbs and turns them into glucose, which is carried in your blood to all the cells in your body, and gives you energy.
Your cells can only use so much glucose at one time, this leftover glucose is stored in your liver and muscles, and called glycogen. The glycogen that doesn't fit into your liver and muscle cells is turned to fat. Glycogen is released for quick energy when you're exercising. Carbs should account for 55% to 65% of the total calories consumed every day.
Simple carbohydrates are absorbed into your blood much faster, and while they provide some really quick energy, they can often come with lots of fat and lack important vitamins that your body needs. Complex carbs are better when you are exercising or playing in a game, because you can count on them to give you energy that lasts through the five setter.
Sources:
Simple carbohydrates: Apples, bananas, grapes, raisins oranges, pears ice cream and frozen yogurt
Complex carbohydrates: Grains, bread, cereals, pasta, potatoes, rice, oatmeal, pretzels, bagels. corn, potatoes, sweet potatoes, tomatoes, carrots, cucumbers

Fat is the body's major form of energy storage are of two types. Saturated fatty acids come from animal foods like meat, milk, cheese, and some oils that come from plants. Unsaturated fatty acids come from plants and fish.
Fat insulates our bodies from the cold and provides some cushioning for our organs as well as giving our bodies energy. Some fats help to make up important hormones to keep our bodies at the right temperature or keep our blood pressure at the right level. Fat helps you have healthy skin and hair. Good sources of energy for extended endurance training but provide very little energy during high intensity training. Fats should make up not more than 15% of the daily calorie intake. Most athletes would do well to reduce their fat calories by consuming fewer amounts

Avoid in excess: Cheese, peanut butter, butter, fried food, nuts, junk foods, cake, saturated salad oils, gravy, fatty meats

Proteins
Our body uses protein in lots of ways. Protein's biggest job is to build up, keep up, and replace the tissues in your body also supply small amounts of energy for muscular contraction. Your muscles, your organs, even some of your hormones are made up mostly of protein. Proteins make hemoglobin, the part of red blood cells that carries oxygen to every part of your body. It even makes antibodies, the cells that fight off infection and disease. Athletes consume about 2 grams of protein per kilogram of body weight per day, which is more than enough for an active squash player

Sources: Meat, fish, eggs, poultry, milk, cereals, dairy products, beans and nuts

Vitamins
Vitamin A keeps the skin, eyes and reproductive system healthy. Milk products, liver, fish, broccoli, carrot, spinach, cantaloupe, squash and sweet potato.
Vitamin B protects your muscular and nervous systems and helps release energy from food. Whole grain products, enriched breads and cereals
Vitamin C maintains your body cells and connective tissue and may help strengthen the immune system. Broccoli, citrus fruits, strawberries, peppers tomatoes
Vitamin D helps bones absorb calcium to make them strong. Fortified milk, fish, and sunlight.
Vitamin E helps produce red blood cells and may help prevent heart disease. Spinach, vegetable oils, whole grains and nuts
Vitamin K helps the blood clotting process. Broccoli, cabbage, liver, soybeans, green leafy vegetables and alfalfa.

Minerals help the body function properly. They help regulate body fluids, nerve impulses, and muscle contractions. They work along with vitamins to help release energy from food.
Calcium helps build strong bones and teeth, regulate the heartbeat, and contract muscles.
Fluoride helps fight tooth decay.
Iron, one of the most important minerals for athletes, helps red blood cells carry oxygen throughout the body's bloodstream.
Sources:
Calcium-milk products and dark green leafy vegetables (like spinach)
Fluoride- fluorinated water and toothpaste.
Iron-dark green leafy vegetables, raisins, cream of wheat, oatmeal, beans, vegetarian chili, eggs, fish, legumes, liver, meat and poultry


Water
A calorie free source of fluid, used to keep your body going during exercise. Your heart rate increases 8 beats per minute for every litre of sweat lost. Dark urine indicates inadequate re-hydration. Drink at least 2 cups of water for every 15 min of exercise.