Protein timing is a popular dietary strategy designed to optimize the adaptive response to exercise. The strategy involves consuming protein in and around a training session in an effort to facilitate muscular repair and remodeling, and thereby enhance post-exercise strength- and hypertrophy-related adaptations. Despite the apparent biological plausibility of the strategy, however, the effectiveness of protein timing in chronic training studies has been decidedly mixed. The purpose of this paper therefore was to conduct a multi-level meta-regression of randomized controlled trials to determine whether protein timing is a viable strategy for enhancing post-exercise muscular adaptations. The strength analysis comprised 478 subjects and 96 ESs, nested within 41 treatment or control groups and 20 studies. The hypertrophy analysis comprised 525 subjects and 132 ESs, nested with 47 treatment or control groups and 23 studies. A simple pooled analysis of protein timing without controlling for covariates showed a small to moderate effect on muscle hypertrophy with no significant effect found on muscle strength. In the full meta-regression model controlling for all covariates, however, no significant differences were found between treatment and control for strength or hypertrophy. The reduced model was not significantly different from the full model for either strength or hypertrophy. With respect to hypertrophy, total protein intake was the strongest predictor of ES magnitude. These results refute the commonly held belief that the timing of protein intake in and around a training session is critical to muscular adaptations and indicate that consuming adequate protein in combination with resistance exercise is the key factor for maximizing muscle protein accretion.
Some athletes and bodybuilders use so-called "dietary supplements" that are legal, unregulated substances in the United States. These substances are not subject to the same testing for safety and effectiveness as all over-the-counter and prescription medications in the . Most of their effects are believed to be hugely overstated by their marketers, but no one really knows what the effects might be. In addition, no one really knows what their dangers might be. On of these supplements is called Andro. It is a legal substance that the body converts into testosterone, a regulated steroid. How efficiently this converted testosterone might be used is unknown. Scientists have not been able to prove that Andro creates desirable effects. In addition, it may be as harmful as other types of testosterone and synthetic testosterone.