If you are wondering what nutrient timing is, well, then it is precisely what the name says it is. Nutrient timing is all about consuming certain foods at specific times to help you reach performance goals. Nutrient timing can be important for enhancing sports performance, aiding fat loss, and promoting muscle growth. However, even though nutrient timing is a popular concept, there is very little convincing data available on this. Read on to find out more about the importance of nutrient timing.
What is Nutrient Timing?
Nutrient timing refers to eating certain foods at specific times of the day to achieve some preset performance goals. For example, having a protein shake after a strenuous workout in the gym. Many athletes use the strategy of nutrient timing to help improve their performance, boost weight loss, and also promote muscle building.(1, 2, 3)
Nutrient timing is not a new concept. In fact, it has been used regularly by professional athletes and bodybuilders for the last five decades, and a lot of studies have been done on it.(4, 5, 6)
Many nutritional books and programs also promote the benefits of nutrient timing as one of the most effective methods of losing fat, improving sports performance, and gaining muscle.
However, when you take a closer look at the research that has been done, the findings are pretty inconclusive, and there were several significant limitations in the way the studies were carried out as well.(7, 8) Two of the biggest limitations were that many of the studies only measured short-term blood markers and were mostly done on extreme endurance athletes, who do not really represent the average person.
This is why the findings of many of these studies that support the benefits of nutrient timing might not be applicable to everyone. Let’s take a look if nutrient timing actually works or not.
What is the Anabolic Window, and Is It Even Real?
The essential part of nutrient timing is known as the anabolic window.(9) Also called the window of opportunity, the anabolic window depends on the idea that the body remains in a perfect state that is most effective for nutrient absorption. This state occurs within 15 to 60 minutes after exercise. However, the research on this anabolic window remains inconclusive, but it is still regarded as an important theory by many fitness enthusiasts and professional athletes.
The theory of this anabolic window depends on two main principles:
- Protein intake: When you exercise, it breaks down the protein in the body. This is why consuming protein after your exercise session can help in repairing the muscles and also boosts muscle growth as it stimulates muscle protein synthesis. (MPS).(10)
- Replenishment of carbohydrates: After exercising, getting a supply of carbohydrates immediately can help boost the body’s glycogen stores, which helps improve performance and also boosts recovery.
Both of these principles are right to some extent, but the fact is that the exact role of nutrition and human metabolism is not as straightforward as some people would assume. The first aspect of the anabolic window focuses on using protein for boosting muscle protein synthesis (MPS), which has an essential role to play in the recovery and growth of your muscles. However, MPS and nutrient replenishment are both important parts of the recovery process, but research has shown that there is no need for this immediately after exercising. Instead of this, you should focus on the total daily intake of protein while also ensuring that you consume high-quality protein with every meal. A meta-analysis concluded that the daily intake of protein and nutrients is what is important.(11)
So if you are meeting your total daily requirement for protein, other nutrients, and calories, the anabolic window is not as important as most people believe it to be. However, the exception to this is professional athletes and people who train several times in a day and need to recharge or maximize their fuel intake between each session.
The second aspect of the concept of the anabolic window is the replenishment of carbohydrates, as carbs are macronutrients stored in the muscles and liver in the form of glycogen. Studies have shown that glycogen gets replenished at a faster rate within half an hour to an hour after exercising. This lends support to the theory of anabolic window.(12, 13)
However, the timing related to the anabolic window is only important if you are working out several times a day or you have a couple of athletic events lined up within a day or two. But for the average person who only exercises once in a day, there is a lot of time within which they can replenish their glycogen during every meal.(14)
Is There Any Relation Between Nutrient Timing and Exercise?
Many experts feel that rather than focusing on the anabolic window, it is more important to focus on the pre-workout window. Depending on your training goals, the right time for taking your supplements might actually help boost your performance.(15) For example, if you are taking performance-boosting supplements such as caffeine, they need to be consumed at just the right time to have the maximum effect.(16)
The same concept is applicable to food as well. When you have a well-balanced and nutritious meal 60 to 150 minutes before working out, it can help boost your performance. This is especially true if you have not had anything for several hours.(17)
However, if you want to lose weight, then training with little food will help you burn more fat and also improve insulin sensitivity, along with many other benefits in the long run.(18, 19)
At the same time, another factor that is very important to your health and performance is your water intake. Many people are often dehydrated before they start working out. This is why it is necessary to drink at least 300 to 450 ml of water (12-16 oz) and electrolytes before you start exercising.(20)
Nutrient Timing at Breakfast and at Night
Most of us have grown up hearing that breakfast is the most important meal of the day. However, recent research has shown that it actually does not matter if you have your breakfast or not. Instead of this, what is more, important is what you have for breakfast.
Many experts recommend having a high-fat, low-carb breakfast that can help boost your energy levels, enhance mental function, improve fat burning, and also keep you full for a longer time. However, most of these observations still remain unsupported by research and are mostly anecdotal.(21)
While some other studies have shown that breakfasts that are rich in protein-based foods have more health benefits, but this is believed to be because of the many health benefits of protein, and the timing is not believed to play much of a role.(22)
So just like the anabolic window, the breakfast myth is also not yet supported by scientific evidence. Nevertheless, consuming a high-fat, low-carb breakfast can have some benefits, though your breakfast should just depend on your own dietary preferences and training goals.
Similarly, as with the breakfast myth, there is a common saying that recommends cutting out carbs from your dinner if you want to lose weight. Again, this decrease in your carbohydrate intake will help you lower your total daily calorie intake and also help create a calorie deficit that may promote weight loss, but the timing has nothing to do with it.
In fact, in contrast to cutting our carbohydrates at night, some studies have actually shown that eating carbs at night can actually promote better sleep and relaxation. However, more research is still needed to confirm this.(23)
It is believed that this might be true as carbohydrates are known to release a neurotransmitter known as serotonin that helps promote better sleep while also regulating your sleep cycle. So when you look at the many health benefits of a good night’s rest, taking carbs at night might actually help you, especially if you have disturbed sleep.
Conclusion: So Does Nutrient Timing Really Matter?
For professional athletes and bodybuilders, nutrient timing can help provide them with a competitive advantage. However, for the average person, research does not support the fact that nutrient timing is essential to gain muscle mass, improving health, or even losing weight. Instead of focusing on nutrient timing, you should focus on your daily calorie intake and on consuming a well-balanced and nutritious diet.
- Kerksick, C.M., Arent, S., Schoenfeld, B.J., Stout, J.R., Campbell, B., Wilborn, C.D., Taylor, L., Kalman, D., Smith-Ryan, A.E., Kreider, R.B. and Willoughby, D., 2017. International Society of Sports Nutrition position stand: nutrient timing. Journal of the international society of sports nutrition, 14(1), p.33.
- Aragon, A.A. and Schoenfeld, B.J., 2013. Nutrient timing revisited: is there a post-exercise anabolic window?. Journal of the international society of sports nutrition, 10(1), p.5.
- Arent, S.M., Cintineo, H.P., McFadden, B.A., Chandler, A.J. and Arent, M.A., 2020. Nutrient timing: a garage door of opportunity?. Nutrients, 12(7), p.1948.
- Ivy, J.L., 2004. Regulation of muscle glycogen repletion, muscle protein synthesis and repair following exercise. Journal of sports science & medicine, 3(3), p.131.
- Burke, L.M., 1997. Nutrition for post-exercise recovery. Australian journal of science and medicine in sport, 29(1), pp.3-10.
- Poole, C., Wilborn, C., Taylor, L. and Kerksick, C., 2010. The role of post-exercise nutrient administration on muscle protein synthesis and glycogen synthesis. Journal of sports science & medicine, 9(3), p.354.
- Aragon, A.A. and Schoenfeld, B.J. (2013) Nutrient timing revisited: Is there a post-exercise anabolic window?, Journal of the International Society of Sports Nutrition. BioMed Central. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3577439/ (Accessed: November 10, 2022).
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- Lemon, P.W., Berardi, J.M. and Noreen, E.E., 2002. The role of protein and amino acid supplements in the athlete’s diet: does type or timing of ingestion matter?. Current sports medicine reports, 1(4), pp.214-221.
- Atherton, P.J. and Smith, K., 2012. Muscle protein synthesis in response to nutrition and exercise. The Journal of physiology, 590(5), pp.1049-1057.
- Schoenfeld, B.J., Aragon, A.A. and Krieger, J.W., 2013. The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. Journal of the International Society of Sports Nutrition, 10(1), p.53.
- Jentjens, R. and Jeukendrup, A.E., 2003. Determinants of post-exercise glycogen synthesis during short-term recovery. Sports Medicine, 33(2), pp.117-144.
- Ivy, J.L., Katz, A.L., Cutler, C.L., Sherman, W.M. and Coyle, E.F., 1988. Muscle glycogen synthesis after exercise: effect of time of carbohydrate ingestion. Journal of applied physiology, 64(4), pp.1480-1485.
- Piehl, K., 1974. Time course for refilling of glycogen stores in human muscle fibres following exercise‐induced glycogen depletion. Acta physiologica scandinavica, 90(2), pp.297-302.
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- Ryan, E.J., Kim, C.H., Fickes, E.J., Williamson, M., Muller, M.D., Barkley, J.E., Gunstad, J. and Glickman, E.L., 2013. Caffeine gum and cycling performance: a timing study. The Journal of Strength & Conditioning Research, 27(1), pp.259-264.
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- Van Proeyen, K., Szlufcik, K., Nielens, H., Ramaekers, M. and Hespel, P., 2011. Beneficial metabolic adaptations due to endurance exercise training in the fasted state. Journal of applied physiology.
- Sawka, M.N., Burke, L.M., Eichner, E.R., Maughan, R.J., Montain, S.J. and Stachenfeld, N.S., 2007. American College of Sports Medicine position stand. Exercise and fluid replacement. Medicine and science in sports and exercise, 39(2), pp.377-390.
- de Graaf, C., Hulshof, T., Weststrate, J.A. and Jas, P., 1992. Short-term effects of different amounts of protein, fats, and carbohydrates on satiety. The American journal of clinical nutrition, 55(1), pp.33-38.
- Leidy, H.J., Ortinau, L.C., Douglas, S.M. and Hoertel, H.A., 2013. Beneficial effects of a higher-protein breakfast on the appetitive, hormonal, and neural signals controlling energy intake regulation in overweight/obese,“breakfast-skipping,” late-adolescent girls. The American journal of clinical nutrition, 97(4), pp.677-688.
- Afaghi, A., O’Connor, H. and Chow, C.M., 2007. High-glycemic-index carbohydrate meals shorten sleep onset. The American journal of clinical nutrition, 85(2), pp.426-430.