Taking protein at night is a huge trend these days, but what do we know?

Does Overnight Protein Work?

Scientists Weight In

The concept of overnight protein has become trendy in the cycling and triathlon community. Predictably so, few concepts sell better than “Get faster while you sleep.” The theory behind this sounds quite good. Your body repairs itself while you sleep, so giving it more building blocks to work with should help it repair more effectively. Just because things sound good doesn’t mean that they’re effective (just look at altitude masks, they’re bunk), so what does the research say? A group of scientists published a recent review on this topic and the results are quite interesting.

A review published in the Journal of Sport and Exercise Nutrition in 2019 dug into this topic. As a review, it pooled data from multiple scientific studies to find consensus in the research and identify the answer to this question. Reviews are high on the evidence hierarchy and help us keep science up to date and complete. The researchers assessed data from 9 studies to provide a more complete picture of the data than any one individual study could. So, can you get faster just by taking some protein before bed? Maybe.

The Research

The point of taking protein is to stimulate muscle synthesis. We normally don’t think of nutrition in such stark terms, but that’s the real point of protein, to help your body synthesize muscle. That gives researchers a good jumping off point in studying this, and a simple question to answer. Does overnight protein cause an increase in muscle synthesis? And, if so, by how much?

The short answer is yes! It does! But not the way we’d like it to. The researchers found that taking protein before bed significantly increases muscle protein synthesis, leading to increased strength in study participants. Unfortunately, the research doesn’t show that there’s any special advantage to taking the protein at night. It’s just as well to take it during the day, supplementing with protein at whatever time is most convenient for you. According to these studies, overnight protein has little advantage.

There’s significant debate out there about nutrient timing, but we just don’t have much data to suggest that there’s an ideal nutritional window for protein, at least one that includes overnight. Overnight protein is a great way to introduce more protein into a diet, but it’s not a panacea that will provide better results than protein supplementation at other parts of the day.

What Protein Should You Take, and When?

The study pulls on other research to provide good and interesting general guidelines about protein supplementation. It recommends ensuring your protein source has sufficient leucine (an essential amino acid), especially for people over 65. A different study from the Journal of Physiology showed that 40% leucine was required for elderly men to gain muscle mass as quickly as younger men. Normal whey protein is about 10% leucine, so leucine supplementation with another source (like pills or a specialized powder) is recommended to make these gains.

Beyond that, taking protein soon after working out is the only piece of the nutrient timing puzzle that we have down pat, so be sure to take it within a few hours of exercise. Many say that protein within 1 hour is required, but there’s very little data available to back up that claim. Anything within a window of a few hours should be sufficient.

The last bit of interesting data out of this review is the realization that protein requirements may be on a dose-response basis rather than determined by your weight. Most nutrition guidelines are given on a per kg or per pound basis, but the authors found that protein requirements are more determined by activity than by the mass of the participant. This leads to some takeaway guidelines.

The Takeaway

• Overnight protein supplementation is not superior to taking protein during the day. It can be helpful to get in a full daily dose, but is not better by its own merit.
• High leucine protein supplementation is needed in people over age 65, and higher doses of overall protein are needed as well.
• A minimum of 40 grams of protein is needed to induce significant muscle synthesis in people over 65, 30 grams is sufficient for younger individuals.
• Protein needs are dose-response, not weight based. Take more protein for harder workouts and less for easier ones.

Sources

Snijders T, Trommelen J, Kouw IWK, Holwerda AM, Verdijk LB, van Loon LJC. The Impact of Pre-sleep Protein Ingestion on the Skeletal Muscle Adaptive Response to Exercise in Humans: An Update. Front Nutr. 2019;6:17. doi:10.3389/fnut.2019.00017

Katsanos CS, Kobayashi H, Sheffield-Moore M, Aarsland A, Wolfe RR. A high proportion of leucine is required for optimal stimulation of the rate of muscle protein synthesis by essential amino acids in the elderly. American Journal of Physiology-Endocrinology and Metabolism. 2006;291(2):E381-E387. doi:10.1152/ajpendo.00488.2005

Luke is a cycling coach and physiologist from Richmond, VA who rides and races bikes all over the country. He’s an expert on the body in motion and its response to exercise and loves to share his knowledge with others. Find him @LukeHollomon everywhere.