The following is a guest-post from Seiji Ishii, well known to readers of the RCTM forum as “Coach Seiji”.  Coach Seiji has an extensive background in Exercise Physiology, has coached world-class athletes in various sports, including stints working for Carmichael Training Systems and Ultrafit.  He currently trains professional supercross/motocross athletes and operates a CrossFit gym in Austin, TX. During his free time he’s working to revive his dormant rock climbing career.


Coach Seiji

It is a well-known and researched practice by even recreational athletes to ingest protein directly after both endurance and strength training as it has repeatedly shown to aid in positive protein balance and thus stimulate protein synthesis.  This increases recovery rates and muscle adaptive response to each subsequent training bout, making training more efficient. Several research groups have and are still studying the optimal amount and type of protein. Reading studies related to this up to 2013 have shown that increasing the amount of protein ingested in a single dose post-exercise increases the amount of protein synthesis (up to 20g, at which point the rate of protein synthesis is maximized). Several types of protein have been studied, including dairy-based proteins like whey, casein and casein protein hydrolysate, as well as whole milk, fat free milk, and yes, even chocolate milk. Soy and egg protein have also been studied. I haven’t found that many studies comparing protein synthesis rates of the various kinds of proteins, but what has been shown is that milk protein and its isolates, whey and casein, perform better than soy.  Furthermore, whey seems to stimulate a larger protein synthesis response than casein. These differences arise from the differences in amino acid profile and digestion and absorption kinetics.

The timing of protein ingestion has also been studied; it has been shown that consuming protein right after training produces a better protein balance than waiting a few hours. It has also been shown that consuming carbohydrates with the protein further enhances muscle protein building due to the quicker delivery of amino acids to the muscle cells. Ingesting protein both before and during exercise has to stimulate muscle protein synthesis during the exercise bout.

Coach Seiji crushing at Sitting Bull Falls, NM.

Coach Seiji crushing at Sitting Bull Falls, NM.

All of this is good of course, but the surprising thing is that studies have shown that overnight muscle synthesis rates are not positively affected by post exercise protein intake, even when the training and subsequent protein supplementation ocurred in the evening. Muscle protein synthesis rates were even lower in the morning than with an overnight fast! Bummer!

I located a study that specifically addressed if protein administered during sleep affected protein synthesis rates compared to fasting overnight, then the same with ingesting protein just prior to sleeping.


Luc J.C. van Loon, researcher, and recreational athletes that performed a resistance training bout at 8pm.


Protein supplementation both directly before sleep, and during sleep, and its effects on overnight muscle protein synthesis.


Athletes have ingested 20-25g of protein directly after training bouts as it has shown to increase muscle protein building in the crucial recovery period.  However, even if this happens in the evening, no positive effects have been shown on overnight muscle protein synthesis. This could be due to the slowing of digestion and other related processes that would reduce the amount of amino acids available in the plasma during sleep. Regardless of cause, this seemingly doesn’t take advantage of the most restorative time in the athlete’s 24-hour period. The purpose of this analysis is to find a way to take advantage of this time to optimize recovery and make training more efficient in the long term.


Department of Movement Sciences of Maastricht University of the Netherlands


First published by the American College of Sports Medicine in 2012


The first method studied was to supplement protein through a nasogastric tube (tube going in through the nose into the stomach) during sleep. The casein protein had a tracer on it both prior to ingestion, then again with a different tracer administered via IV drip throughout the night to track the protein once it entered the plasma.

The second method involved recreational athletes, who all ate nutritionally equally during the day, performed their strength training bout at 8 pm, and then ingested 20g protein/60g carbohydrate at 9 pm.  These subjects then ingested a recovery drink 30 minutes prior to sleep that contained either  40g of casein protein with tracer, or a placebo. Sleep time was standardized to 7.5 hours.


The protein delivered via feeding tube did increase muscle protein syntheisis rates overnight compared to no feeding overnight. The tracer proved that the casein protein was indeed digested, caused an increase in the concentration of amino acids in the plasma, and wound up in new muscle proteins by morning. The 40g protein drink given 30 min prior to sleep also increased amino acid concentration in plasma, increased protein synthesis rates compared to the drink that didn’t contain protein, and the tracer was found in the newly assembled muscle proteins in the morning.

The subjects that received the 40g protein recovery drink showed both reduced protein breakdown during the night, an average increase of 22% of protein synthesis for a much improved overall overnight protein balance during the 7.5 hours of sleep.

My take:

This is all good! Much better overnight muscle recovery with the ingestion of the 40g protein 30 min before sleep. This, to me, is an awesome benefit to daily recovery and long term effectiveness and efficiency of training, for very little effort.

My suggestion would be to do this after any strength training day and any heavy day of training. I would find the type or mixtures of proteins that work the best for you, both in terms of digestion and effects on your sleep. I do think that this varies depending on the person and I do think that what you eat before you sleep can affect your sleep (I am researching what types of proteins affect sleep in what way after reading this study), so you need to experiment to find what works best. I do think finding easily digestible protein matters, as digestion rates do slow during sleep. Easily digestible protein sources will create less work for your body during sleep, freeing up more energy to devote to other recovery tasks.  Also, the amount of work your body has to do to digest the protein can negatively affect sleep from what I have observed.

Bottom Line:

  • 20-25 g Protein with each meal
  • 20-25g Protein right after exercise
  • Can consider some Protein with Carbohydrate during exercise, but in most people I know and myself, protein during exercise can cause GI stress/GI slowdown thus negatively effecting hydration and carbohydrate fueling. This also seems worse as exercise intensity increases. In these cases, to me, it’s not worth the downsides at all for the upside of increased protein synthesis during the exercise bout.
  • 20-40g Protein right before bed, not to exceed 30 min prior to sleeping

Heck ya! Enjoy the benefits of increased muscle recovery while you sleep! It doesn’t get much easier than that.

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