Soccer is the world’s most popular sport. As the sport has grown, so have the physical demands and the search for ways to edge out the competition with the use of sports science and nutrition. The demands, which include intense training, ≥90 minutes matches, congested fixtures, and travel, lead to increased energy and nutrient requirements, stress on the body, and risk of impaired sleep cycles. Identifying key areas to enhance a player’s performance is an ongoing effort because of individual differences. Moreover, new information is being discovered via research, and advancing technology to measure performance is always evolving. This article focuses on the core nutrition principles known to lay the foundation for a better soccer player. These principles are obvious for some; however, nutrition and hydration are often undervalued, leaving the individual player with the responsibility to eat right. This review addresses the most applicable nutrition-related recommendations for soccer players.
Technical, tactical, and physical skills are key factors in a soccer player’s performance. However, energy demands of matches and training sessions require adequate fuel and hydration to maximize those key factors. Athletes may need to manage carbohydrates, protein, and fat separately to achieve optimal body size and body composition, and to maximize performance.
Nutrition plays a vital role in keeping the player healthy, reducing risk of injuries, speeding up recovery, and enhancing training adaptations. Research has shown what we eat and when we eat can significantly impact skeletal muscle adaptation, inflammation, immune response, and energy metabolism. These are all essential nutrition considerations for soccer players.
ENERGY METABOLISM IN SOCCER
Understanding energy demands will help determine energy requirements: type, amount, and timing of macronutrients and micronutrients. Soccer utilizes both aerobic and anaerobic energy systems. Soccer is an intermittent team-based sport; thus, it contains various high-intensity movements, such as sprinting, jumping, dribbling, and frequent changing of direction performed in between numerous low-intensity slow movements. The high intense movements collectively account for about 30% of match play, whereas 70% is walking, jogging, and standing. Although sprinting and jumping are not a large part of the 90 minutes of match play, they have a huge impact on the outcome of the match. Distance covered in the last 15 minutes of match play decreases by 14% to 45% compared with the first 15 minutes of play.1 Krustrup and colleagues2 found muscles in the quadriceps to be empty or nearly empty of glycogen (stored carbohydrates) after match play. This phenomenon can help explain a significant decrease in sprinting, jumping, and intermittent movements toward the end of a match—energy demands that rely on glycogen as the primary fuel source. Being well-fueled and hydrated and having the ability to delay fatigue can place a team at a performance advantage.
Beyond training load or match intensity, a soccer player’s body composition, gender, age, and position can affect energy needs. Position differences in elite soccer players show that the greatest total distance covered is by central midfielders and wide midfielders (~12 km –13 km), whereas central defenders cover the least area of the field players (≤~10 km).3,4 The environment can also play a role in energy expenditure. To further understand calorie needs, total daily energy expenditure in soccer players has been measured using doubly labeled water and estimated using heart rate, global positioning system, video match analysis, and activity records.5,6 One study estimated that energy expended during a training day for elite male soccer players is between 3442 kcal and 3824 kcal.6 Another study using doubly labeled water concluded that mean energy expenditure of elite male soccer players is 3566 kcal over a 7-day period, which included 5 training days and 2 matches.7 In terms of energy expenditure for elite female soccer players, the mean values for match day, training days, and rest days were 2914, 2783, and 2213 calories, respectively.8
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