Over the past 20 years, research has clearly documented the beneficial effect of nutrition on athletic performance. Proper nutrition is critical not only to your athletic success, but also and more importantly to your growth, development and overall health. Inadequate nutrient intake deprives your body of the energy needed to perform an event, the carbohydrates necessary for glycogen replacement, the protein needed for tissue building and repair, and the micronutrients necessary for normal metabolism and maintenance of body homeostasis.

Energy balance for the athlete is the amount of energy the athlete consumes (food calories) necessary to balance the amount of energy the athlete expends (activity). Physical activity does influence the amount of specific nutrients required and the optimal timing of their intake. The athlete, who is engaged in heavy training, will have higher energy and nutritional requirements. Total energy intake must be sufficient to offset the energy expended during athletic training and performance.

Energy Availability

Many athletes spend a great deal of their time and effort maintaining and manipulating energy balance. Manipulating energy balance has extremely important implications that affect not only your body weight, but also your proportion of fat mass and fat-free mass, carbohydrate stores, bone health, vitamin and minerals status, and menstrual status in women. Energy availability = total energy – energy cost of training/competition (ideally this should be >30 kcal/kg FFM/day).

Your energy requirements are influenced by the energy expenditure of your training load (intensity, frequency and duration) along with your body size, growth and pursuit of weight loss or gain. The role of your nutritional regimen is to supply you with the fuel and nutrients needed to optimize the adaptations achieved during your training and to ensure recovery between your workouts. Low carbohydrate intake can result in inadequate glycogen stores, premature fatigue and possible utilization of the body’s protein stores for energy. It is important that you have adequate fuel stored in your muscles (muscle glycogen) and adequate hydration to optimize your performance. Arguably, carbohydrates are the recommended source of energy needs from intense training.