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When you finish this chapter you will be able to:

  • Identify the six classes of nutrients and describe their major functions.

  • Explain the importance of good nutrition in enhancing performance and preventing injuries.

  • Describe the advantages or disadvantages of dietary supplementation in the athlete’s diet.

  • Discuss common eating and drinking practices in the athletic population.

  • Explain the distinction between body weight and body composition.

  • Explain the principle of caloric balance and how to assess it.

  • Describe methods for losing and gaining weight.

  • List the signs of disordered eating.


The relation of nutrition, diet, and weight control to overall health and fitness is an important aspect of any training and conditioning program for an athlete.13 Athletes who practice sound nutritional habits reduce the likelihood of injury by maintaining a higher standard of healthful living.63 Eating a well-balanced diet can positively contribute to the development of strength, flexibility, and cardiorespiratory endurance.1 Unfortunately, misconceptions, fads, and, in many cases, superstitions regarding nutrition affect dietary habits, particularly in the athletic population.9

Many athletes associate successful performance with the consumption of special foods or supplements.35 An athlete who is performing well may be reluctant to change dietary habits regardless of whether the diet is physiologically beneficial to overall health. The psychological aspect of allowing the athlete to eat whatever he or she is most comfortable with can greatly affect performance. The problem is that these eating habits tend to become accepted as beneficial and may become traditional when in fact they may be physiologically detrimental to athletic performance. Thus, many nutrition “experts” may disseminate nutritional information based on traditional rather than experimental information.

Although this chapter provides information on basic nutrition, the focus is on how this information relates specifically to the athlete. Despite the fact that there are great differences in what individual athletes like to eat, it is also true that there are many different ways that athletes can obtain the nutrients they need. However, athletes who engage in poor nutritional practices and habits are not doing everything possible to optimize their performance.9


People usually think of losing weight when they hear the word diet. Actually, diet refers to a person’s usual food selections. What people choose to eat is their diet. Everyone is on a diet based on the foods they choose. Although people have different food likes and dislikes, everyone must eat to survive. Nutrition is the science of certain food substances, nutrients, and what they do in the body.63 Nutrients perform three major roles:

Six classes of nutrients:

  • Carbohydrates

  • Fats

  • Proteins

  • Vitamins

  • Minerals

  • Water

  1. Grow, repair, and maintain all body cells

  2. Regulate body processes

  3. Supply energy for cells


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