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Nutrition For Optimal Performance And Recovery
Thomas M. Best, MD, PhD, FACSM
The Ohio State University
Fundamental to any discussion about human health and performance is the recognition of
proper nutrition as a platform from which to build upon and optimize one’s overall quality of
life across the lifespan. Children and adolescents require proper nutrition and adequate energy
intake for proper growth, development, and maturation. Beyond that, the needs for sport
performance and recovery although recognized as important, are largely extrapolated from
adult requirements (4). Therefore, more research is needed about nutritional requirements for
young athletes. Similarly, although nutritional needs due to aging and processes such as
sarcopenia are well studied, the nutritional needs of healthy aging athletes are not well studied.
It has been suggested that there is no scientific reason to assume that older athletes will
respond differently to the pre- and during-race fluid and carbohydrate replacement strategies
suggested for younger athletes, however evidence to support this assertion is lacking (6).
Sport and athletics include a wide range of events whose requirements range from speed to
endurance, from a light physique to explosive power, and from multiple events lasting less than
a minute to a single competition lasting more than 2-3 hours. Despite this tremendous
variability, athletes share common nutrition requirements that are closely tied to optimal
performance. It is important to remember that proper nutrition improves performance in a
number of ways, perhaps most importantly through energy availability – that is the amount of
energy left for normal body functions once the energy cost of training is taken into account.
There is convincing evidence that for most people, energy availability lower than 30 kcal (126
kJ) per kg of lean body mass is associated with impairments of metabolic, hormonal, and
reproductive function. In this paper, we will review some of the emerging topics on sports
nutrition and their importance to optimal performance and recovery following training and
competition. This topic is of particular importance given the recent suggestion that many
athletes are unaware that poor eating habits and suboptimal hydration may detract from
optimal performance (3).
Vitamins, minerals, anti-oxidants
Almost everyone recognizes the advantages of supplements containing whey and casein
protein, arginine and others in building muscle mass. Increasingly, the importance of vitamins
such as vitamin C, vitamin D, and folic acid (to name a few) are recognized as vital for both
health maintenance and your body’s ability to add muscle mass.
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In general, vitamin and mineral supplements are not needed if adequate energy to maintain
body weight is consumed from a variety of food groups (1). However, the micronutrients most
likely to be consumed in inadequate amounts are iron and calcium, particularly in athletes who
restrict energy intake, use severe weight-loss practices or eliminate or more food groups from
their diet. It is important to remember that the prevalence of iron deficiency anemia in
athletes is similar to the general population but that there is a higher prevalence of iron
deficiency without anemia (normal hemoglobin but serum ferritin below 20-30 ng/ml). The
latter condition is associated with a reduced response to aerobic training. The condition can
often be managed by the athlete and a sport medicine physician and/or nutritionist through
dietary changes including; use of small servings of red meats, shellfish, liver and increased
consumption of plant iron e.g. fortified breakfast cereals, nuts and legumes, wholegrain cereals
and green leafy vegetables. Orange juice and Vitamin C both aid in iron absorption and are
practical adjuncts to helping increase and maintain body iron stores.
Protein needs
Protein is most important for muscle growth and development. An area of expanding research
in recent years has been the comparative effects of different protein sources on physical
activity as well as the advantages and disadvantages of animal versus vegetable protein sources
and their implications on athletic performance. Whether heavy training increases protein
requirements is still a topic of great debate. The current thinking is still that for most strength
and endurance athletes, the requirement is 1.2 – 1.6 g/kg body mass per day. Surveys have
shown that most athletes, especially those consuming high-energy intakes, meet those
requirements. Athletes who are most at risk of not meeting this requirement are the female
endurance athletes who restrict total energy intake to lose weight. The optimal strategy for
maintenance of daily requirements in these higher risk groups is still a matter of debate
although blends of dairy protein and soy protein in commercial sports nutrition products such
as nutrition bars and ready to drink sports nutrition and powdered beverages appear to meet
most individuals’ needs.
Eating for recovery
Nutrition-related aspects of recovery include refueling, rehydration, tissue rebuilding, and
maintenance of overall health. Your post workout drink should ideally include protein in
addition to carbs, even if you’re doing aerobic exercise. Recovery eating probably requires
about 10 – 20 gm of high quality protein and 1gm/kg body weight of carbohydrate within the
hour following exercise. Recent studies suggest that adding small amounts of protein during the
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early phases of recovery positively affect subsequent exercise performance and may be of
particular benefit to athletes involved in multiple training or competition events on the same or
consecutive days (2). The post exercise protein boost may be even more important for aging
people according to recent studies in humans showing that a protein-only drink improved
skeletal muscle structure better than a carbohydrate-only drink (6).
Hydration
It is also important to remember that proper hydration is critical to optimal performance. In
order to perform at your highest level, you need to be properly hydrated. Monitoring weight
changes before and after training sessions and competitions can provide a reasonable estimate
of sweat rate (1 kg loss  1 liter of sweat) and therefore help to develop a personalized fluid
intake plan.
Fluid replacement does not begin and end with water only. The composition and temperature of a
drink and the volume and rate of its consumption can all influence the physiological responses to
ingestion and can impact on exercise performance. Sports drinks hydrate you better than plain
water, largely because fluids are absorbed through the gut and into the bloodstream faster
when their concentration of nutrients best matches that of blood itself. Most sports drinks
contain dissolved minerals (e.g. sodium) and carbohydrates and therefore reach the
bloodstream more quickly than plain water. Recent research suggests that in addition to
improving hydration and minimizing the risk of problems such as dilutional hyponatremia, as
little as 1 to 2% dehydration can impair visual-motor tracking, training focus, and reaction time.
Another advantage of sports drinks over water is that the former provide additional energy
during exercise. The carbohydrate content of sports drinks provides your muscles with an
additional source of fuel that is valuable in both endurance and high-intensity sports. This can
best be achieved by consuming solutions containing 4-8% carbohydrates for any event lasting
longer than 60-90 minutes. In addition to providing energy, the carbohydrate in sports drinks
reduces muscle damage by limiting the release of the stress hormone cortisol. A growing trend
is the addition of protein or amino acids to further limit exercise-associated muscle damage and
increase fluid retention (5, 7).
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References
1. American College of Sports Medicine position stand. Nutrition and athletic performance.
Med Sci Sports Exerc 41(3): 709-731, 2009.
2. Beelen M, Burke LM, Gibala MJ, van Loon L JC. Nutritional strategies to promote
postexercise recovery. Int J Sport Nutr Exerc Metab 20(6): 515-532, 2010.
3. Bonci LJ. Eating for performance: bringing science to the training table. Clin Sports Med
30(3): 661-670, 2011.
4. Jeukendrup A, Cronin L. Nutrition and elite young athletes. Med Sport Sci 56: 47-58,
2011.
5. Shirreffs SM, Watson P, Maughan RJ. Milk as an effective post-exercise rehydration
drink. Br J Nutr 98(1): 173-180, 2007.
6. Tarnopolsky MA. Nutritional considerations in the aging athlete. Clin J Sport Med 18(6):
531-538, 2008.
7. Watson P, Love TD, Maughan RJ, Shiffeffs SM. A comparison of the effects of mild and a
carbohydrate-electrolyte drink on the restoration of fluid balance and exercise capacity
in a hot, humid environment. Eur J Appl Physiol 104(4): 633-642, 2008.
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