The 3 Principles of Sports Nutrition

Nutrition for Special Groups 3(3+0)

Lesson 30: Sports Nutrition

The 3 Principles of Sports Nutrition


Water is the most important factor in sports nutrition. Water makes up approximately 60% of body weight and is involved in almost every body process. Body cannot make or store water, so must replace the water eliminated in the urine and sweat.

Everyone should drink at least 2 quarts (8 cups) of water each day, and athletes need more. Plenty of fluids should be consumed before, during, and after sports events to stay hydrated and to avoid overheating. When they work out or compete, especially in hot weather, the amount of fluid to drink should match with the amount lost in sweat.

Cool water is the best fluid to keep hydrated during workouts or events that last an hour or less. Sports drinks containing 6% to 10% carbohydrates are useful for longer events. Most sports drinks should be diluted with approximately 50% water.
Some tips for staying hydrated:

  • Drink small amounts of water frequently, rather than large amounts less often.
  • Drink cold beverages to cool core body temperature and reduce sweating.
  • Weigh yourself after working out, and drink 2 to 3 cups of water for every pound lost. Body weight should be back to normal before the next workout.
  • Pay attention to the amount and color of urine. Excrete a large volume that is nearly colorless. Small amounts of urine or dark yellow-colored urine can indicate dehydration.


  • Carbohydrates are the primary muscle fuel for most types of exercise.
  • 60–90 minutes of endurance training or a few hours in the weight room can seriously deplete carbohydrate muscle fuel stores.
  • Starting exercise with full carbohydrate stores can delay the onset of fatigue and help in training or competing more effectively.
  • Workouts and performance during competitions suffer if the diet is too low in carbohydrates.

There are 2 forms of carbohydrate in the body.

  • Glucose,which circulates in the bloodstream
  • Glycogen, which is bundles of glucose stored in the liver and muscles
  • About 40 calories of glucose in the bloodstream
  • About 1,900 calories stored as glycogen in the muscles, plus liver glycogen


Workouts and competitions deplete the glycogen stores.
Muscle tissue is damaged as the athlete trains and competes, and require repair.
Muscles are also being stimulated to adapt to the training workload.

Recovery includes

  • Reloading carbohydrate fuel stores
  • Repairing and building new muscle tissue
  • Rehydrating

The recovery process doesn’t start after exercise provide the body is provided with the nutritional components it needs:

In order to promote rapid recovery, as soon as possible after training or competing (within 30–60 minutes), consume:

  • Carbohydrates for glycogen restoration
  • Protein for repairing and building new muscle tissue
  • Fluids and sodium for rehydration
Last modified: Tuesday, 8 May 2012, 10:09 AM