Louise M. Burke, OAM, Ph.D., APD, FACSM, is a program director with Sportsoracle. Sportsoracle provides educational and consulting services in sport and exercise sciences and sports medicine to various sporting and commercial bodies.
Sports nutrition is a dynamic discipline that integrates many themes including sports science, clinical dietetics, food culture, and the psychology of eating. It is challenging to work in sports nutrition because of the speed of changes to scientific knowledge, real-world practice, and our food environment. The popularity of social media has recently added new challenges by creating a platform from which oversimplified nutrition advice can be dispensed in the absence of appropriate qualifications or an evidence base. A new position stand on nutrition for athletic performance tackles these challenges.
Well-chosen nutrition strategies offer athletes a vast number of opportunities to support training programs, maintain health, optimize performance, and achieve well-being. In trying to do justice to all the potential areas for dietary intervention, the authors of this new position stand identified a number of unifying themes. An understanding of the principles provided below should motivate practitioners, scientists, athletes, and coaches to appreciate the value of nutrition in sports performance and move toward even better research and applications.
Top ten themes in sports nutrition:
1. Nutrition goals and requirements are not static. Athletes undertake periodized programs in which they aim to peak for targeted events by integrating different types of workouts into the various cycles of the training calendar. Nutrition support also needs to be periodized from day to day, across the training cycles, and over the athlete’s career. The starting point is to consider the needs of the daily training sessions, which can range from minor, in the case of easy workouts, to substantial in the case of strenuous, high-quality sessions. Targeted eating for each session should then be integrated into the bigger plan that accommodates longer term nutritional goals.
2. Nutrition plans need to be personalized to the individual athlete to take into account the specificity and uniqueness of his or her event, performance goals, and practical challenges. Food preferences and individual responses to various strategies will differ between athletes.
3. Energy availability, which considers energy intake in relation to the energy cost of exercise, sets an important foundation for health and the success of sports nutrition strategies. Low energy availability, caused by a restriction in energy intake and/or an increase in exercise volume, can occur in a range of different settings and individuals, and therefore, different approaches are needed to tackle it.
4. Achieving the body composition associated with optimal performance, or body mass targets associated with weight category sports, is a challenging goal that needs to be individualized and periodized. Care should be taken to preserve health and long-term performance by avoiding practices that create unacceptably low energy availability and psychological stress.
5. Training and nutrition interact to stimulate the body to adapt its metabolism and function. Although active nutrition support is needed to promote optimal performance, training adaptations may sometimes be enhanced by an opposite approach. For example, exercising with low glycogen stores or in the absence of carbohydrate intake creates a greater stimulus inside the muscle and promotes greater outcomes in many of the adaptive pathways. Athletes might mix and match their nutritional approach to different training sessions according to whether the goal of the workout is to train hard (with maximizing performance or quality of training as a priority) or to train smart (with the goal of maximizing cellular adaptations).
6. Guidelines for some nutrients — such as energy, carbohydrate, and protein — should be expressed per kilogram of body mass to allow recommendations to be scaled to the large range in the body sizes of athletes. Sports nutrition guidelines also should consider the importance of the timing of nutrient intake and nutritional support over the day and in relation to sport rather than general daily targets. For example, the message to spread high-quality protein over the day is now becoming well known. The target to consume protein-rich foods after exercise, and at meals or snacks spaced every 3 to 5 hours, should replace both the old daily Recommended Dietary Intakes (RDIs) and habitual eating practices in which people eat most of their daily intake in the evening meal.
7. Highly trained athletes walk a tightrope between training hard enough to achieve a maximal training stimulus and avoiding the illness and injury risk associated with an excessive training volume. Nutrition strategies can help to maintain balance.
8. Competition nutrition strategies should target the factors that would otherwise cause fatigue in an event. These are specific to the event, the environment/scenario in which it is undertaken, and the individual athlete. Strategies include consuming carbohydrates before, during, and between events to ensure adequate supplies to meet the muscle’s fuel needs. Fluid plans also should be individualized to balance the benefits of replacing fluid to limit dehydration with the opportunities to drink during the event.
9. New performance nutrition options have emerged from developing evidence that the brain senses the presence of carbohydrate and other nutritional components in the mouth and throat. Positive effects include improvements in perceived effort and faster pacing strategies. Practical applications of this new knowledge include consuming or “mouth rinsing” with fluids and foods during shorter events, in which nutrition support previously was not considered to offer an advantage. In addition, there is opportunity to reorganize the behavior or frequency of eating and drinking in longer events so that the central (brain) effects can be maximized while gaining the metabolic or system effects of supplying nutrition support.
10. A pragmatic approach to advice about supplements and sports foods is needed because athletes are keen consumers of these products. Furthermore, there is the evidence that some can contribute usefully to a sports nutrition plan and/or directly enhance performance. Athletes should be assisted to undertake a cost-benefit analysis of the use of such products and to recognize that they are of the greatest value when added to a well-chosen eating plan.
To read this Position Stand in its entirety, visit http://journals.lww.com/acsm-msse/Fulltext/2016/03000/Nutrition_and_Athletic_Performance.25.aspx