Resistance training builds muscularity and strength by promoting anabolism, especially in trained muscle. As such, for a few hours after heavy exercise, your body enters a window of heightened protein synthesis (muscle building) counterbalanced by slight increases in catabolism (muscle breakdown). Science tells us that boosting blood amino acids within this window blunts catabolism and drives protein synthesis up even further; leading to efficient recovery and greater gains. Thus it’s no surprise why most athletes slug back a protein shake on their way out of the gym.
Science also tells us that there is a tight relationship between elevated blood amino acid levels and elevated anabolic state, despite whether you have trained that day or not. That’s right, there are swings in protein synthesis throughout the day that coincide with protein feeding. With this, protein synthesis rates are highest upon the absorption of a high protein meal and taper off throughout the post-absorptive phase, until another protein meal is ingested. This is why you must consume meals regularly throughout the day to maximize progress.
Recently, a research group from the Netherlands published an eloquent review in Nutrients highlighting the importance of daily protein supplementation, noting its ultimate importance prior to sleep. The scientists noted that muscle protein synthesis rates are particularly low during sleep, even when a protein shake is ingested immediately after training in the evening. However, when athletic subjects ingested 40 g of casein protein before bed, they were able to boost protein synthesis rates by about 22% throughout the entire night compared to a placebo! They concluded that greater amino acid availability during sleep stimulates muscle protein synthesis rates and improves whole body protein net balance during overnight recovery.
ACTION POINT: To promote robust stimulation of muscle protein synthesis rates throughout the night, ingest at least 40g of high quality micellar casein or sustained release protein blend immediately before bedtime on training and rest days.
Reference: Trommelen J, van Loon LJ. Pre-Sleep Protein Ingestion to Improve the Skeletal Muscle Adaptive Response to Exercise Training. Nutrients. 2016 Nov 28;8(12).