Protein before bed equals bigger gains? New review reveals the scoop

08 Mar 2019 --- Overnight sleep provides a unique nutritional window for boosting the muscle response to resistance training – without increasing body fat, a review published in Frontiers in Nutrition has confirmed. The review notes that the evidence supporting pre-sleep protein intake is “encouraging,” although further research is warranted.

The rise in consumer knowledge around health and nutrition has spurred protein’s popularity, especially within the athletic scene, as consumers search for the most efficient way to gain muscle. The continued mainstreaming of the sports nutrition sector is also having a profound impact on new product activity and is partly spurring recent innovation in protein. Innova Market Insights has reported strong growth in sports-related positionings within mainstream food and beverage NPD, such as a 188 percent growth in new products with a high/source of protein positioning.

“Several one-night studies have shown that pre-sleep protein intake increases muscle protein synthesis during overnight sleep in young adults,” says lead author Dr. Tim Snijders, Assistant Professor at Maastricht University. “These have fueled the idea that over a longer period, a pre-sleep protein supplement can maximize the strength and muscle mass gains during regular resistance exercise training.”

Snijders’ 2015 study is a strong demonstration for this.

In that study, the team put 44 healthy young men on a 12-week lifting program. Half were given a nightly pre-sleep protein shake with about 30g of casein and 15 grams of carbs, while the other half got an energy-free drink.

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The question posed in the review was whether muscle gains are boosted by pre-sleep protein or just a higher total intake of protein and calories.

The training was effective – both groups ended with a bigger squat (one repetition max) and bigger quads – but the protein-before-bed group gained significantly more muscle strength and size.

Is pre-sleep protein consumption better?
The question posed in the review was whether muscle gains are boosted by pre-sleep protein or just a higher total intake of protein and calories.

Just one study has attempted – unsuccessfully – to test this question, the review noted. It showed that fat-free mass gains over eight weeks of unaltered training in regular lifters were greater (+1.2 kg vs. +0.4 kg) with a nightly casein supplement, compared to the same supplement taken in the morning. The difference was not statistically significant, however, perhaps because there were only 26 participants.

“Based on our own studies, we calculated that a huge number of participants would be needed to prove whether a difference might exist in response to pre-sleep protein, versus protein intake at other times of the day,” explains Snijders.

However, there are already numerous indirect indicators that pre-sleep protein specifically is beneficial for healthy young lifters.

Sleep is a unique opportunity for muscle recovery and growth
Fundamentally, pre-sleep protein can be used to improve protein intake distribution over the day, says Snijders.

Muscles can only grow and repair themselves when the right building blocks – amino acids from protein – are available in the blood. But unlike blood glucose, the body does not store and release amino acids to maintain near-constant circulating levels.

“A survey of over 500 athletes found they were typically consuming a total of more than 1.2g protein per kilo of bodyweight across three main meals, but only an insignificant 7g of protein as an evening snack. As a result, lower levels of amino acids would be available for muscle growth during overnight sleep,” Snijders says.

But if pre-sleep protein consumption allows muscles to cram in more amino acids at night, will they simply use less during the day? Apparently not, claims Snijders.

“The muscle-building effects of protein supplementation at each meal seem to be additive. In one study we found that the consumption of ample amounts of protein (60g whey) before overnight sleep did not alter the muscle protein synthetic response to a high-protein breakfast the following morning,” he says.

“What's more, others have shown that adding a protein supplement at bedtime does not affect appetite the following morning – so it is unlikely to compromise total protein or calorie intake.”

Bedtime protein won't “make you fat” or ruin your sleep
The case for pre-sleep protein remains preliminary, but the evidence is encouraging. 

“In the 8-week morning vs. evening casein study, the additional consumption of protein calories did not result in any increase in fat mass despite the fact that exercise volume did not change,” reports Snijders. “But again, these results should be interpreted with caution due to the low number of volunteers included.”

“Supporting this, another group found in 11 young active men that a pre-sleep casein shake actually increased the rate of fat burning the following day. This might be because casein ingestion reduces the insulin response to subsequent meals, which pushes your body to use more fat.”

Based on these studies’ results, pre-bed protein consumption, especially casein, doesn’t appear to “make you fat.” It appears actually to increase fat metabolism.

In a concluding note, Snijder says that there is not yet conclusive evidence for adding a pre-sleep protein supplement to fitness regimes, but it may be worth a try and it is certainly worth further research.

Protein has been riding a wave of popularity for some time and a host of techniques to boost the macronutrients power have emerged. Recent reporting includes Lactalis Ingredient’s whey protein Pronativ, which uses a technology that allows the whey to be obtained from fresh milk, as opposed to being collected as a by-product of dairy processing. The protein is touted as delivering greater results towards muscle protein synthesis, recovery and performance, compared to regular whey protein, according to the company.

Plasma Nutrition’s Ingredient Optimized technology significantly improves the bioavailability of whey protein, according to a study published in the Journal of Nutrition and Metabolic Insights last month. The findings note that the US start-up’s ioWhey protein improves the absorption of leucine, as well as that of branch chain amino acids (BCAAs) and essential amino acids (EAAs) in general.

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