Medicine & Science in Sports & Exercise:
POST ACCEPTANCE, 9 February 2012

Protein Ingestion Prior To Sleep Improves Post-Exercise Overnight Recovery
Res, Peter T.; Groen, Bart; Pennings, Bart; Beelen, Milou; Wallis, Gareth A.; Gijsen, Annemie P.; Senden, Joan M.G.; van Loon, Luc J.C.

Abstract
Introduction: The role of nutrition in modulating post-exercise overnight recovery remains to be elucidated. We assessed the impact of protein ingestion immediately prior to sleep on digestion and absorption kinetics and protein metabolism during overnight recovery from a single bout of resistance type exercise.

Methods: 16 healthy young males performed a single bout of resistance type exercise in the evening (20:00) after a full day of dietary standardization. All subjects were provided with appropriate recovery nutrition (20 g protein, 60 g carbohydrate) immediately after exercise (21:00). Thereafter, 30 min prior to sleep (23:30 h) subjects ingested a beverage with (PRO) or without (PLA) 40 g specifically produced intrinsically [1-13C]phenylalanine labeled casein protein. Continuous intravenous infusions with [ring-2H5]phenylalanine and [ring-2H2]tyrosine were applied with blood and muscle samples collected to assess protein digestion and absorption kinetics, whole-body protein balance and mixed muscle protein synthesis rates throughout the night (7.5 h).

Results: During sleep casein protein was effectively digested and absorbed resulting in a rapid rise in circulating amino acid levels which were sustained throughout the remainder of the night. Protein ingestion prior to sleep increased whole-body protein synthesis rates (311+/-8 vs 246+/-9 ~mol[middle dot]kg-1[middle dot]7.5 h -1) and improved net protein balance (61+/-5 vs -11+/-6 [mu]mol[middle dot]kg-1[middle dot]7.5 h -1) in the PRO vs PLA experiment, respectively; P<0.01). Mixed muscle protein synthesis rates were ~22% higher in the PRO vs PLA experiment, which reached borderline significance (0.059+/-0.005 vs 0.048+/-0.004 %[middle dot]h-1; P=0.05).

Conclusion: This is the first study to show that protein ingested immediately prior to sleep is effectively digested and absorbed, thereby stimulating muscle protein synthesis and improving whole-body protein balance during post-exercise, overnight recovery.

I would say the Placebo group had less protein. The groups aren’t really equal. The Placebo group should have received 60gm post workout.

Would be good to see someone doing a long term study.

My understanding of the study was to compare a resistance trained group who had protein feeding before sleep to the placebo group who didn’t. I don’t believe they were supposed to be equal. The area I believe that had nutritional equality was the immediate post training feeding. The last feeding I believe was meant to be different.

I know that was the design. I am just saying they have 2 variables here 1) protein before sleep and 2) 40gms more protein.

Is it the protein before sleep or the increase in protein that caused the increase in protein balance? They should have had the placebo group consume 40 gms of protein after their workouts. This way we could have had fair comparison.

I agree with anoop, but I don’t think it would have changed the study. Protein balance increases after feeding, and a feeding earlier in the day probably wouldn’t have had as big an effect on protein balance during sleep as a protein feeding just before sleep would. If you had looked at total protein balance during a 24 hour cycle it might have been different, though. I think the point is that eating protein before bed is a good idea, as there isn’t much else (activity, etc) to stimulate MPS during sleep.

They took the post workout protein at 21:00 and then took the pre-bed protein at 23.00. It was only 2 hrs apart.

If the placebo took the 40gms right after exercise, I am not sure if the night protein would have seen such a difference.

I didn’t know they worked out that late, so you got a point. But why would you have to compare it to a post work out shake? I would have compared it to a shake at some other random time during the day as post workout is another one of those “windows” where it might be better than elsewhere.