Athletes have believed for a very long time, perhaps going back as far as Ancient Greece, that large intakes of protein are necessary for optimal athletic performance. Regardless, modern nutritionists have largely downplayed the importance of this idea. In fact, dietary protein recommendations (~0.8 g/kg/day) in many countries are not adjusted in any way for individuals who exercise regularly, not even for those involved in rigorous daily sport training (FAO/ WHO/UNU, 2007; US Department of Agriculture and US Department of Health and Human Services, 2010).
However, the question of dietary recommendations for athletes has remained controversial for years (Lemon & Nagle, 1981; Lemon, 1987, 1998) and a definitive conclusion on this question still remains unclear for a variety of reasons, partly due to the limitations of available experimental techniques. Briefly, there are data indicating that some types of regular exercise (both strength and endurance) increase dietary protein needs (perhaps by 50–100%) and that some athletes benefit from protein intakes in excess of daily recommendations but there are also conflicting experimental results (Lemon et al., 1992; Tarnopolsky, 2004; Rodrigues et al., 2009).
Further, most scientific studies have focused on protein/amino acid requirements and not athletic performance measures, which of course is the athlete’s primary interest. More data examining both of these areas, especially in elite athletes, are needed to settle this issue.