|Fridge raiding allowed, no even suggested! At least if what you take out of the fridge is a chilled protein shake - preferably one with at least some slow-digesting casein.|
Now, three years later, I am happy to tell you my prediction was not too far off. In fact, the provision of a shake containing 27.5 g of protein, 15 g of carbohydrate, and 0.1 g of fat right before bed even doubled the gains of the those 22 young, recreational active, but non-resistance trained men who had been randomly assigned to the active treatment (the energy-free placebo tasted identical).
Needless to say that Tim Snijders and his colleagues had hypothesized that the provision of extra dietary protein before sleep would "further augment the gains in muscle mass, strength, and muscle fiber size during more prolonged resistance-type exercise training in healthy young men" (Snijders. 2015). That the extra-gains the subjects in the active group saw in response to 12-weeks of resistance training + supplementation would be that significant is yet something the scientists from the Maastricht University probably didn't expect, either.
|Figure 1: Changes in cross sectional area and muscle size of type II fibers (Snijder. 2015).|
What did the exercise program look like? As previously mentioned, the subject trained thrice a week. Their training sessins were supervised and consisted of a a 5-min warm-up on a cycle ergometer that was followed by 4 sets on both the leg press and the leg extension machines (Technogym). While these 2 exercises were performed every training session, the additional exercises varied. More specifically, 2 sets on the chest press and horizontal row were alternated with vertical pull-down and shoulder press between every training session. Each exercise session ended with a 5-min cooling down period on the cycle ergometer. During the first week of the training period, the workload was gradually increased from 70% (10–15 repetitions) of 1RM to 80% of 1RM (8–10 repetitions). Thereafter, training was always performed at 80% 1RM. The weights and thus the workload was progressively increased (Note: Imho, that's the #1 factor why people don't make gains, in the real world: They forget to increase their weights!)
|Figure 2: 1RM increased as well.|
This does not negate the scientists' conclusion that "protein ingestion before sleep represents an effective dietary strategy to augment skeletal muscle mass and strength gains during prolonged resistance-type exercise training in healthy, young men." (Snijder. 2015), but it certainly raises the question if the differences would have been similarly pronounced if the protein intakes had been matched or if the scientist had compared post-workout vs. pre-bed consumption.
- Groen, Bart, et al. "Protein ingestion before sleep improves postexercise overnight recovery." Medicine and science in sports and exercise 44.8 (2012): 1560-1569.
- Snijders, et al. "Protein Ingestion before Sleep Increases Muscle Mass and Strength Gains during Prolonged Resistance-Type Exercise Training in Healthy Young Men." The Journal of Nutrition (2015): Ahead of print.