Soccer

The popularity of soccer worldwide is enormous, and its popularity in the United States is on the rise. Soccer is a wonderful sport from a fitness standpoint because the average distance covered by a typical player during a match is approximately 6 miles (10 kilometers).²⁵ In addition, soccer players appear to have significantly greater bone mineral densities-likely from all the running stresses placed on the bones-than do age- and weight-matched controls. ^26,27 Although much of the activity is aerobic, a large proportion is anaerobic as players sprint for the ball. There is less activity in the second half of a typical soccer game compared with the first, likely the result of unsustained muscle glycogen stores. It was suggested long ago that the ingestion of carbohydrates immediately before, during, and after a game may play an important role in reducing player fatigue during a game. ²⁸ Following this strategy would sustain available glucose and glycogen to working muscles.

In studies of professional soccer players' nutrient consumption, their energy and nutrient intake was similar to that of the general population, despite having a far higher energy and nutrient requirement. ^29,30 Although the recommended training diet for soccer players should include 55 to 65 percent carbohydrate, 12 to 15 percent protein, and less than 30 percent fat,³¹ the athletes in this and other surveys consumed foods that were considerably lower in carbohydrate and higher in fat. ³² A survey of NCAA Division I female soccer players found that their carbohydrate con sumption did not meet the minimum recommendations to promote glycogen repletion (7 to 10 grams per kilogram), but protein and fat intakes were above the recommended level.³³ It is generally believed that playing soccer places a high demand on glycogen stores, so glycogen depletion could cause premature fatigue and reduced performance during a match. ³⁴

The ergogenic benefit of carbohydrate for sports such as soccer was confirmed in a study assessing the combined and separate benefits of carbohydrate and chromium ingestion during intermittent high-intensity exercise to fatigue. Data from this study confirmed the benefit of carbohydrate but did not support the benefit of chromium.³⁵ Of course, adequate energy intake, estimated to be approximately 4,000 calories for males and 3,200 calories for females, is also important. Without sufficient energy intake, glycogen will become depleted regardless of the makeup of the diet. In addition, inadequate caloric intake makes optimal synthesis of phosphocreatine (needed for sudden, quick-burst activity) difficult. This point is emphasized in a study that demonstrated a performance benefit of creatine supplementation in young soccer players, a finding that would be unlikely with adequate energy consumption.³⁶

Keeping this in mind, figure skaters must consider the following nutritionally relevant factors for their sport.

Play in soccer is expected to be continuous, making it difficult for players to consume fluids. Since soccer players may not have an opportunity to regularly consume fluids during a game, pregame hydration status is particularly important. Whenever possible (between periods and during official breaks), players should consume a sports beverage to rehydrate and to replace carbohydrates. A study of soccer players found a wide variability in voluntary fluid intake patterns, with the conclusion that most players fail to adequately hydrate.³⁷

Surveys suggest the consumption of carbohydrates is less than optimal for soccer players, yet carbohydrate consumption is critical for the achievement of optimal soccer performance. According to the surveys, soccer players typically consume diets that match those of the general public, with a carbohydrate intake of around 50 percent of total calories. Players should make a conscious effort to improve carbohydrate intake.

Pregame glycogen storage is critical. Soccer players spend a great deal of time running up and down the field, placing a tremendous drain on muscle glycogen. Players who begin the game with more stored glycogen will experience an endurance advantage. To achieve a higher glycogen storage, players should consistently consume plenty of carbohydrates and fluids and also focus mainly on carbohydrates during the pregame meal.