I recently co-authored a review article with my good friend and colleague Alan Aragon titled, “Nutrient Timing Revisited: Is there a post-exercise anabolic window?” I’m happy to say the article was published in the prestigious Journal of the International Society of Sports Nutrition and has received a lot of favorable attention. Here are the highlights:
1) Nutrient timing can be a beneficial strategy for maximizing muscular gains, but the “window of opportunity” is not necessarily as narrow as often believed.
2) Provided that a protein-rich meal is consumed within about 3-4 hours prior to a workout (or possibly even longer, depending on the size of the meal), you don’t have to stress about chowing down a post-workout meal as soon as you finish training. For those who train partially or fully fasted, on the other hand, consuming protein immediately post-workout becomes increasingly more important to promote anaoblism.
2) Although research is somewhat equivocal, it seems prudent to consume high-quality protein (at a dose of ~0.4-0.5 g/kg of lean body mass) both pre- and post-exercise within about 4-6 hours of each other depending on meal size.
3) Contrary to popular belief, consuming post-exercise carbohydrate does not meaningfully enhance anabolism. Moreover, unless you are performing two-a-day workouts involving the same muscle group(s), glycogen replenishment will not be a limiting factor in those who consume sufficient carbohydrate over the course of a given day. So from a muscle-building standpoint, just focus on meeting your daily carb requirement as opposed to worrying about timing issues.
One of the most surprising aspects of writing this paper was the lack of clarity in the current body of research. Alan and I reviewed every direct study conducted on the subject. Not only were results of these studies highly conflicting, but most had confounding issues that obscured the ability to tease out the impact of the effects of consuming nutrients post-workout. I am planning a study in my lab that addresses the gaps in the literature. Hope to begin data collection in the near future. Stay tuned!
In case you want to delve into the heavy science on the topic, here is a link to a PDF of the article: