Eating And Exercise

Eating And Exercise


Exercise and proper diet work together to promote optimal performance and health. The foods we eat act as the body's energy reserves, fueling our activity levels and daily metabolic functions. Regular exercise can help the body use these fuels more efficiently.

Carbohydrates, Fats and Protein

As mentioned in the exercise physiology section, carbohydrates are stored in the body in the form of glycogen and glucose. Athletes and frequent exercisers require large amounts of complex carbohydrates. The average person should derive 50-55% of total caloric dietary intake from carbohydrates, while competitive athletes may require as much as 65-70% of their diet to come from carbohydrates. The energy from carbohydrates can be released within the muscles approximately three times as fast as energy derived from fat stores.

Large amounts of carbohydrates are needed to provide fuel for high intensity activity as well as to replenish glycogen stores following such exercise sessions.

Be careful about the types of carbohydrates consumed. Complex carbohydrates are normally more nutrient dense than simple carbohydrates, which can contribute to sharp spikes and drops in insulin production. For more information on the differences between complex and simple carbohydrates in relation to exercise and diet, please refer to the Nutrition Guide.

Stored fats represent another source of energy. During light to moderate exercise, stored fat can supply 50-60% of the energy needed. During prolonged aerobic exercise, fat's contribution can increase to 70%.

Current recommendations call for 25-30% of a person's diet to consist of fats. Many athletes and health and fitness minded people are trying to reduce this percentage to 10-20%. As explained in the Nutrition Guide, excessive dietary fat intake is associated with a higher incidence of obesity. In addition, a low-fat, high-carbohydrate intake is recommended to help prevent coronary artery disease, hypertension, non-insulin-dependent diabetes and high levels of blood cholesterol. Still, it is possible to consume too little fat. Remember, the human body requires some fat to function properly.

Protein intake is perhaps the most misunderstood aspect of diet for the athletic community. Current recommendations call for 12-15% of the diet to come from protein. This amount is thought to be more than enough protein to satisfy the needs of the human body.

While some research indicates the hard-training athlete may need significantly more than this, it has not been conclusive. Regardless, the average American consumes double the recommended protein in his daily diet. Excessive protein intake can lead to medical complications, including kidney problems.

Many athletes are under the assumption that by consuming massive amounts of dietary protein, they will enhance muscle growth and development. This misunderstanding arises from the fact that the largest component of muscle besides water is protein.

Protein contributes little energy to performance work. Approximately one to two percent of the total energy that is used for normal exercise is derived from protein sources. Longer durations of exercise may derive up to 5.5% of calories from protein.

Unfortunately, the use of protein as an energy source can be at great expense to the human body. Since the body does not store protein, it must be taken away from its structural roles in the body. Such roles include the building and repair of muscle tissue, hair and fingernail growth, hormone production and replacement of red blood cells. Moreover, large amounts of protein that are not used by the body are broken down by the liver and excreted out of the body by the kidneys. Thus, the more protein you take in, the more stress that is placed on your kidneys and liver. In addition, the extra calories you take in in the form of excess protein are liable to be converted to fat and stored in adipose tissue.

In her book, The Sports Nutrition Guidebook, Nancy Clark, M.S., R.D. recounts current data concerning some safe daily levels of protein intake:

  • Sedentary adult: 0.4 grams per lb. body weight
  • Active adult: 0.4 ­ 0.6 grams per lb. body weight
  • Growing athlete (teenager): 0.6-0.9 grams per lb. body weight
  • Adult athlete building muscle tissue: 0.6-0.9 grams per lb. body weight

    Hydration Considerations

    During exercise, large amounts of water and electrolytes can be lost through perspiration. To avoid dehydration, it is important to consume fluids at regular intervals before, during, and after prolonged exercise. Once you begin activity, your body cannot absorb as much fluid as it loses through sweating and respiration. Thus, it is important to start your activity with extra fluid in your system.

    The type of fluid consumed can be important. High concentrations of simple sugars in fluids can often cause insulin spikes and subsequent low blood sugar levels. Fruit juices are best consumed following the exercise session since they can also provide electrolytes and potassium in addition to the simple carbohydrates and fluid. Commercial "sports drinks" should be examined on an individual basis to determine which ones may be of use to you, if any. For more information concerning such sports drinks, please refer to the sections on supplementation in both the Fitness Expert Activity and Nutrition Guides.

    It is also helpful to remember that cold fluids are thought to empty from the stomach and be absorbed more quickly than warmer beverages. This could help avoid bloating or abdominal cramps during exercise and activity.

    The following hydration guidelines should be taken into consideration before activity or competition:

  • Drink approximately two and a half cups of water two hours before the beginning of your activity.
  • Consume an additional one and a half to two and a half cups of water about fifteen minutes before engaging in an activity.
  • Drink 4-6 ounces of water every fifteen minutes during exercise.
  • After exercise, continue drinking water, usually two to three cups.

    For additional hydration guidelines, refer to the sports nutrition section in your Nutrition Guide.

    The Pre-Event Meal

    "Pre-game" meals have been the subject of much debate. The main consideration in planning your pre-activity meals should be that you provide yourself with adequate calories and fluids to prevent weakness or dehydration during the activity session.

    There is a psychological as well as a physical aspect to the pre-event meal. While avoiding foods that would impair performance, you should also choose those foods that you feel comfortable with.

    We recommend that you eat a small to medium-sized meal approximately two to four hours before the activity. This should prevent feelings of hunger during the event without causing bloating or sluggishness, a frequent result of large, protein and fat-laden meals.

    Complex carbohydrates should be the cornerstone of all pre-activity meals. Simple carbohydrates like high-sugar foods usually result in a quick energy surge and resulting plunge in blood sugar (hypoglycemia), which will leave you feeling weaker than if you had eaten nothing at all.

    Try to avoid gas-producing foods or items that you know will bloat you or cause discomfort.

    Make sure you drink 2-3 cups of fluid with your meal to assure proper hydration.

    Some people find liquid meals to be ideal pre-event items, since they tend to leave the stomach quicker than solid foods. Others complain that large amounts of liquid cause stomach and intestinal discomfort.

    Experiment for yourself with such variations. Remember to conduct such experiments on practice days, not the event day itself. The last thing you want to discover an hour before an important event is that a certain food makes you feel weak, bloated, nauseous or shaky.

    For more information concerning the pre-activity meal, please refer to the Nutrition Guide.

    Weight Loss

    Competition in certain activities may require participants to lose weight. Unfortunately, such weight loss practices are often done in an unsafe manner. These methods include, but are not limited to, drastic caloric reduction and maintenance of very low-calorie diets for extended time periods, fluid deprivation and self-induced dehydration, and fasting. To complicate matters further, such practices may be carried out in conjunction with strenuous exercise activity. Such a dangerous combination is both performance-debilitating as well as health-threatening.

    Weight loss, for any athlete or fitness enthusiast, is best accomplished with a sensible, nutritionally-balanced caloric intake combined with a well-thought-out, safe exercise program. This method should allow your caloric expenditure to exceed your intake.

    Athletes, or any other person, should attempt to lose no more than 1-2 lbs. per week. This should allow most of your weight loss to result from lost body fat. Greater amounts of weight loss may involve losing hard-earned muscle mass and water. Thus, one should plan ahead of time, allowing for the proper number of weeks to achieve the desired weight. As such, the competitor will not have to worry about decreased performance and strength levels from drastic weight loss and fluid deprivation.

    For further information pertaining to weight control, refer to the Nutrition Guide.

    Weight Gain

    As with weight loss, individuals need to concentrate on safe, effective methods to facilitate weight gain. Athletes may build some muscle mass as a result of their activities, which would contribute to weight gain. For those athletes who need to gain weight for performance purposes or to move up a weight class, such as an Olympic weight lifter or wrestler, they should concentrate on eating more frequently. This will help boost caloric intake levels.

    If increasing the frequency of eating nutritious foods is not a possibility, the athlete should then concentrate on altering the size of his regular meals. By choosing higher calorie foods, the athlete can consume a greater number of calories than before. If his activity level remains constant, a caloric surplus will result.

    Some athletes have a hard time increasing the amount or frequency of daily meals. For these people, a high-calorie, carbohydrate-based beverage might prove useful between meals. Protein powders would also be an alternative, although hard-training athletes should choose carbohydrates as the bulk of their diet.

    One needs to remember that even when striving to increase caloric consumption, the proper dietary ratios of 50-70% carbohydrate, 25-30% fat and 12-15% protein should be maintained.

    For some people, gaining weight while engaged in high energy-demanding activities can be difficult. Still, the athlete should set up a plan that allows him to achieve his desired weight by gaining 1-2 lbs. per week. This rate of weight gain should allow the competitor to avoid the negative effects of gaining weight too rapidly.

    Such negative effects may include a loss of flexibility or agility since one may not be used to performing the same sport-specific movements with the extra

    Tips to Increase Your Daily Activity Levels

    There are a variety of ways to increase the number of calories you burn on a daily basis. These methods may seem inconsequential at first, but they can add up quickly. These activities can help bring your caloric intake and expenditure levels closer together and help you control your weight. In addition, they are useful steps in transforming a sedentary lifestyle into one that is more active.

    11 easy ways to increase your level of activity:

  • Take the stairs instead of escalators and elevators.
  • Walk instead of driving to nearby destinations.
  • Finish each meal with a relaxing five or ten minute walk.
  • When watching TV, use the commercials as a cue for performing calisthenic exercises like push-ups and trunk curls.
  • Begin each morning with a short, easy session of calisthenic and flexibility work.
  • About an hour before bedtime, relax yourself with a leisurely walk and stretching session.
  • While relaxing in a pool during nice weather, engage in simple, active movements involving your arms or legs, such as high-stepping, side stepping, arm raises or side swings.
  • Park your car farther than usual from your destination and walk the extra distance.
  • If you use public transportation, get off a stop earlier and cover the difference by walking.
  • Take an "exercise break" in place of a coffee break, performing activities such as walking around the office, walking up the stairs, or even simple, low-exertion calisthenics like knee bends or arm circling. The rejuvenating effect of these activities will probably last longer than caffeine, without the following "crash."
  • Eat small amounts of low-fat food at regular, frequent intervals throughout the day as opposed to one or two large meals.

  • Fitness Facts home

    © 1992-2017, All rights reserved. May not be reproduced in any medium without written permission.