Taking Protein Before Bed May Result in Better Muscle Gains
Sports Nutrition
Drinking a casein shake just before sleep increases gains in muscle mass and strength in response to resistance exercise. But to date, no study has directly addressed whether this effect is due to increased total protein intake only, or if a bedtime beverage is better.
According to a review published in Frontiers in Nutrition, existing findings suggest that overnight sleep provides a unique nutritional window for boosting muscle gains without increasing body fat.
“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 (The Netherlands). “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 included 44 healthy young men engaged in 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. The training was effective—both groups ended with a bigger squat (one rep max) and bigger quads—but the protein-before-bed group gained significantly more muscle strength and size.
Fundamentally, pre-sleep protein can be used to improve protein intake distribution over the day, according to Snijders. Muscles can only grow and repair themselves when amino acids from protein are available in the blood. “A survey of over 500 athletes found they were typically consuming at total of more than 1.2 g protein per kilo of bodyweight across three main meals, but only a paltry 7 g of protein as an evening snack. As a result, lower levels of amino acids would be available for muscle growth during overnight sleep,” he reported.
In his 2019 update, he writes that the muscle-building effects of protein supplementation at each meal seem to be additive. In one study he and his team found that the consumption of ample amounts of protein (60 g whey) before overnight sleep did not alter the muscle protein synthetic response to a high-protein breakfast the following morning.
“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,” he said.
Snijders T, et al. “The Impact of Pre-sleep Protein Ingestion on the Skeletal Muscle Adaptive Response to Exercise in Humans: An Update.” Frontiers in Nutrition, 2019; 6 DOI: 10.3389/fnut.2019.00017.
