Study under review: Pre-sleep dietary protein-derived amino acids are incorporated in myofibrillar protein during post-exercise overnight recovery
Consuming nutrients, primarily protein, during and around exercise to maximize training adaptations and facilitate repair and recovery has been a heavily investigated topic over the past several decades. This practice is a standard recommendation among sports nutrition authorities like the International Society of Sports Nutrition and American College of Sports Medicine.
Nutrient timing strategies vary depending on the athlete and their goals, but the post-exercise period is generally considered to be of special importance due to the depletion of stored energy and damage to muscle fibers that occurs during exercise. Although a single exercise session increases muscle protein synthesis for up to 48 hours, overall muscle protein balance is negative without nutritional intervention. Consuming protein after training has been shown to shift muscle protein balance from a negative to a positive state, as depicted in Figure 1.
Adapted from: Trommelen J & van Loon LJ. Nutrients. 2016 Nov.
However, the muscle-full effect proposes that protein ingestion stimulates muscle protein synthesis for only two to three hours, after which rates begin to decline, even when there is a continuous supply of amino acids. Accordingly, eating multiple meals after training appears necessary to maximize increases in muscle protein synthesis throughout the day. Yet, many people train in the evening after a full day of regular physical activity and food intake, eating only once or twice again before going to sleep and beginning an overnight fast.
Previous research has shown that supplementing with 40 grams of casein before bed results in significant elevations of muscle protein synthesis throughout the night. The study under review is a follow-up study that sought to determine whether a more moderate amount of protein would affect muscle protein synthesis rates.
Nutrient timing is a common and heavily investigated practice among athletes for maximizing training adaptations and facilitating repair and recovery. Consuming protein post-workout has been shown to stimulate muscle protein synthesis, but this effect only lasts for a couple hours, requiring further feeding for further stimulation. The study under review sought to evaluate whether consuming casein protein before sleep would augment overnight rates of muscle protein synthesis.
Other Articles in Issue #32 (June 2017)
Another look at the diet-heart hypothesis
When you replace saturated fat with polyunsaturated fat, some studies suggest that good things should happen. But there’s more than one way to interpret the available studies.
Can chondroitin save knee cartilage?
Chondroitin’s mixed results for slowing the progression of osteoarthritis may be due to the low-quality or lower-dose chondroitin used in some studies. Looking at the structural effects of higher-dose, pharmaceutical-grade chondroitin could shed more light on its efficacy
Protein, fast and slow
Fast-digesting whey helps with post-workout muscle protein synthesis, and some studies suggest slower-digesting casein reduces muscle protein breakdown. This opens the possibility that their combination could be better than either alone
Interview: Matthew Dalby, PhD
Dr. Dalby’s research explores the links between diet, obesity, and the microbiome. In this interview, we discuss fecal transplants, the role of animal models in research, and more.
Should 1000 IU be the new RDA for vitamin D?
Since it was set in 2010, the 600 IU vitamin D RDA has been widely circulated. But a close look at individual patient data may give a more accurate estimate of vitamin D needs.
Better performance with nitrate supplementation?
Nitrates are one of the few supplements that consistently show promise for athletic performance. But should you take them acutely or chronically for best effect?
Interview: Kenneth Brown, MD
Dr. Brown is an accomplished gastroenterologist who has conducted clinical trials on supplements and drugs for GI conditions. We pick his brain here