Nutrient timing

Nutrient timing is planning what to eat before, during and after training to support the body’s response to exercise.^{1Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 234.} Hard training uses stored fuel and damages muscle fibers, while exercise makes muscle more responsive to nutrients.^{1Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 234.} Protein taken around a resistance session raises muscle protein synthesis more than a placebo does.^{1Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 234.}

That doesn’t establish a muscle-size benefit: a meta-analysis of 23 studies found a small effect for protein taken within an hour of training, but almost all of it came from higher overall protein intake in the timed groups (about 1.7 versus 1.3 g/kg a day).^{2Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 235.} When intake was matched, timing made no significant difference.^{2Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 235.} The anabolic window also appears much wider than the often-quoted hour.^{3Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 237.}

In practice

Helms and colleagues advise novices and their coaches to get the bigger parts of the nutrition plan in place before focusing on workout meal timing.^{4Helms et al., The Muscle & Strength Pyramid: Nutrition, 2nd ed., p. 131.}

Schoenfeld suggests about 0.4 to 0.5 g/kg of lean body mass of high-quality protein both before and after training, with those meals roughly 4 to 6 hours apart.^{5Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 238.} Clients who train fasted should eat protein soon afterward, preferably within 45 minutes.^{5Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 238.}

Rapid glycogen replenishment only matters when the same muscles are trained twice in one day; otherwise, adequate daily carbohydrate refills stores within 24 hours.^{3Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 237.} Carbohydrate timing matters more for endurance athletes facing a second glycogen-depleting session or a multistage event.^{6Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 126.}