It seems simple enough. The body burns energy through daily living and exercise, and food and drinks replace that energy. When the amount of energy expended in a day roughly equals the amount taken in, it's called energy balance.

It sounds simple, but the bodies and lives of adolescents — particularly females — are often in a state of rapid and unpredictable change. Add to this a variety of factors that can make energy balance and good nutrition difficult to achieve. These include:

Increased nutritional needs that go unaccounted for.

As young girls grow, they need more calories to maintain energy balance simply because their body mass is increasing. In addition, if girls play sports, an uptick in the amount of exercise at practice may not be accounted for nutritionally.

The longer and harder young athletes exercise, the more calories that are burned, but young athletes don't always eat more to compensate for the added activity. With bodies and activities in constant flux, nutritional habits that were once adequate might no longer be. 

A lack of knowledge or misinformation on nutrition.

Teens can excel at calculus or history — or even health class. Still, many adolescents and young adults struggle to pull knowledge and action together into a consistent, practical approach to optimal nutrition.

Parents also can lack specific nutrition knowledge, or their advice and planning goes unheeded. Young athletes often have less ability to separate valid sources of dietary advice from speculative or outright wrong information.

Moreover, well-meaning teens might follow the nutritional practices of overweight, inactive friends or family members — but those practices don't work well for a growing, active teen.

Difficulty planning ahead for food needs.

Practice ends and it's off to the evening football game and a hot dog from the concession stand for dinner, or even worse, nothing at all. School lunch isn't appealing and goes untouched. The ability to plan ahead for nutritional needs in a hectic day is tough for anyone, and not surprisingly, teens also struggle with this important habit.

Dietary restrictions, such as being vegetarian.

Young athletes might choose to go vegetarian, restrict carbs, or follow other dietary restraints or restrictions. However, they might not have a plan for making up crucial lost nutrients, such as protein, iron, calcium or vitamin B-12.

These restrictions can make it difficult to take in enough calories and essential nutrients, especially with the increased energy demands of participating in sports. 

Perceived or real pressure to be lean or thin.

Distorted thinking about body size or image — and how diet and exercise plays into this — can lead to serious nutritional deficits. While clinical eating disorders, such as anorexia and bulimia, are serious issues in female sports and athletics, the most common nutritional issue is consuming too few calories to support optimal health and performance.

Adolescents and young people simply might not eat enough, or they might have other dietary beliefs or behaviors that limit their ability to achieve energy balance. Examples include disguising dieting through vegetarianism, using diet pills or exercising compulsively to achieve a very low weight.

Inadequate nutritional intake and disordered eating habits aren't always obvious. They can occur in adolescents and young adults of any weight, shape or size.

Knowledge is the best defense.

One of the best ways to make sure energy and nutritional intakes stay at healthy levels is by getting educated. Girls can benefit from help and input from parents, coaches, or a registered dietitian, sports nutritionist or other health care professional. Along with learning the basics of a healthy diet and energy balance, young female athletes need to know these key facts:

  • Prolonged, inadequate calorie intake — whether purposeful or not — is a threat to health and to optimal sports performance.
  • Nutritional needs are likely to increase and change with growth in body size and increased activity.
  • Good nutrition generally involves planning and effort.
  • A focus on healthy eating is preferable to diets that emphasize weight, body image or short-term performance gains.


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