Immunological aspects of sport nutrition

Abstract

Prolonged bouts of exercise and heavy training regimens are associated with depression of immune system functions which can increase the risk of picking up opportunistic infections such as the common cold and influenza. Some common sport nutrition practices including high carbohydrate diets and carbohydrate ingestion during exercise, training with low glycogen stores, intentional dieting for weight loss, ingestion of high dose antioxidant supplements and protein ingestion post-exercise may influence immune system status in athletes. In order to maintain robust immunity, athletes need to consume a well-balanced diet that is sufficient to meet their requirements for energy, carbohydrate, protein, and micronutrients. Dietary deficiencies of protein and specific micronutrients are well known to be potential causes of immune dysfunction and an adequate intake of some essential minerals including iron and zinc and the vitamins A, D, E, B6 and B12 are important to maintain a healthy immune function. Vitamin D may be a particular concern as recent studies have emphasised its importance in limiting infection episode incidence and duration in both the general population and in athletes and many individuals exhibit inadequate vitamin D status during the winter months. There is only limited evidence that individual amino acids, -glucans, herbal extracts and zinc are capable of boosting immunity or reducing infection risk in athletes. The ingestion of carbohydrate during exercise and daily consumption of probiotics, vitamin D3, bovine colostrum, and plant polyphenol containing supplements or foodstuffs currently offer the best chance of success, particularly for those individuals who are prone to illness.

Sports injury and illness epidemiology during the 2014 Youth Olympic Games: United States Olympic Team Surveillance

“…Other proposed risk factors include low vitamin D status, high training load and training-associated immune system depression 25–27. There is some evidence for illness prevention programmes, including the use of probiotics prior to travel, addressing micronutrient deficiency, and addressing the quantity and timing of macronutrient intake 27. Education regarding illness prevention should be a priority in the planning stages for NOC's preparing for major events.…”

How much is too much? (Part 2) International Olympic Committee consensus statement on load in sport and risk of illness

“…These early warning clinical symptoms and signs may indicate acute illness, but can also be symptomatic of over-reaching and overtraining. 37 There is also good evidence that markers of subclinical (asymptomatic) illness, including changes in the immune system, can occur in response to acute and chronic exercise [50][51][52][53] and that some of these changes may predict the onset of acute illness. 54-60 To Figure 1 Well-being continuum.…”

Papel del huevo en la dieta de deportistas y personas físicamente activas

“…Durante el ejercicio aumenta el consumo de oxígeno y esto produce un mayor estrés oxidativo y producción de radicales libres (18), por lo que las necesidades de nutrientes antioxidantes pueden estar incrementadas en deportistas. Además, el entrenamiento prolongado e intenso afecta negativamente al sistema inmunológico del deportista, por lo que es importante una ingesta adecuada de proteínas y algunos micronutrientes involucrados en la respuesta inmune como son el hierro, zinc, y vitaminas A, D, E, B 6 y B 12 (19).…”