Reading Time: 5 minutes 30 seconds
BY: ISSA
DATE: 2024-06-14
As a trainer, clients will often turn to you when they have questions about their diet. They may want to know what to eat for maximum muscle gain, for instance. Or they might wonder if certain diet plans can help speed up their fat loss.
The type of nutrition advice trainers can provide varies based on your state’s laws and your training certifications. But one topic that can typically be discussed is nutrient timing.
Nutrient timing involves eating at specific times to achieve a desired outcome. This outcome can vary depending on the client’s goals. (The goal helps dictate the timing strategy.) Nutrient timing to increase muscle mass looks different than if the goal is weight loss, for example.
Generally, the timing of nutrition is centered around the training session. It breaks down what should be consumed before or even during the workout. It also guides post workout nutrition. Together, this is known as peri-exercise nutrient timing.
Nutrient timing even provides advice about what to eat. It gives insight into when carb intake might be the most important. (Are pre workout carbs better than post workout carbs?) It also breaks down how to time protein intake.
In an editorial published by Nutrition, it explains that nutrition timing is based on three phases:
Energy phase: This is when the muscle releases enough energy to contract during exercise. Carbohydrate consumption at this time helps keep muscle glycogen stores from depleting. It also helps keep blood sugar from crashing. This reduces fatigue. Add protein to the mix and muscle can exert more effort. It also stunts the rise of cortisol, aiding in muscle recovery.
Anabolic phase: The 45 minutes after a workout is the anabolic phase. This is when damaged muscle protein starts to repair. Muscle glycogen stores are starting to restore. During this phase, insulin sensitivity initially increases, then drops rapidly. Several hours after exercise, insulin resistance can occur. This can slow muscle recovery and repair.
Growth phase: The growth phase starts after the anabolic stage ends and continues until a new workout begins. Muscle hypertrophy occurs during this phase. Muscle glycogen is also fully replenished.
While timing nutrition may seem like a lot of work, it does get easier with practice. Plus, there are quite a few benefits in timing your meal or snack.
Nutrient timing can help maximize muscle growth. A 2018 study reported that consuming whey protein after lower-body resistance training contributed to greater rectus femoris muscle size.
Timing your nutrition can also aid in fat loss. One study found that consuming a 1;1.5 carbohydrate and protein supplement before training resulted in greater fat oxidation 30 minutes after the exercise ended. Another study reports that nutrient timing also affects metabolism.
If the goal is improved performance, nutrition timing can help with this too. Research supports pre-exercise carbohydrate consumption for endurance athletes. It may be even more critical when resistance training according to an article in the Journal of Athletic Performance and Nutrition. This article explains that it works by reducing protein degradation and increasing protein synthesis.
Some research even suggests that the timing of other substances may offer more benefits. A 2022 study looked at the timing of ergogenic aids and micronutrients. It noted that timing caffeine, nitrates, and creatine affect exercise performance. This timing also impacts the ability to gain strength and for the body to adapt to exercise.
The strategy you use when timing nutrition will vary based on your desired goal.
Protein is key to helping muscle grow. It is also critical for boosting muscle strength. Consuming protein during the anabolic phase can help muscle repair after resistance exercise. It can even help reduce muscle protein breakdown the next morning according to one study.
Consuming 20 grams of protein after exercise helps support muscle protein synthesis. While it may be tempting to aim for more, one study found that this provides no additional benefit. It’s also important to stay within your recommended protein intake.
Protein needs vary based on the level of physical activity. An athlete engaged in moderate-intensity exercise needs 0.71 to 0.9 grams of protein per kilogram of body weight per day (g/kg/day). An athlete engaging in more intense exercise needs more, or between 1.2 and 1.7 g/kg/day. Those engaging in resistance exercise also need this higher amount.
What does nutrient timing look like if the goal is weight loss? Much of the research in this area involves eating habits, in general, as opposed to eating before, during, or after exercise.
One study that addresses this topic focuses on endurance athletes. It notes that fat loss can be achieved for this type of athlete by:
Carbohydrate intake: training in a fasted state
Protein intake: scattered throughout the day (every 3 to 5 hours)
The path to fat loss without losing muscle changes depends on exercise intensity. If the intensity is high, increased carbohydrate consumption can help meet this demand. If the workout is low intensity, focus more on protein.
Performance nutrition is gaining in popularity. Some suggest that access to a sports dietitian can improve performance for pro athletes. This is the basis of an April 2022 article published in the Journal of the International Society of Sports Nutrition.
The strategy for nutrition timing varies based on the sport. If the athlete runs marathons, fueling up a few hours before the run provides energy for the event. Carbohydrate foods are best. A good calorie count is 400 calories or less. After the race, refuel with a light meal.
If the sport relies on muscle strength, refuel with protein within a few hours. This helps the body as it repairs muscle damage. Approximately 20 grams is a good place to start. More may be needed if the sport is intense.
Nutrition timing can also change depending on the type of workout.
A carbohydrate-rich meal a few hours before aerobic exercise helps provide the energy needed. Adding a little protein can help keep the energy going. Have a banana (carbohydrate) with some peanut butter (protein). Or eat a couple of wheat crackers (carbohydrate) with cubes of cheese (protein).
When lifting weights, post-exercise protein is important. This will help the muscle tissue recover. It also aids in skeletal muscle growth. Aim to consume this protein within a few hours. A protein shake is an easy option. Scrambling some eggs or having a salad with chicken are more options.
An endurance athlete needs enough energy to sustain movement long-term. This involves fueling the body with a high-carbohydrate meal a few hours before the training. If the training session is long, a carbohydrate snack may be needed during the workout. Afterward, have a light meal that includes both protein and carbs.
Sports nutrition is an ever-changing field. And every person is different. What works for one client or athlete may not work for another. Some may benefit from carbohydrate ingestion before exercise while others gain the most advantage by exercising in a fasted state.
Working with a sports nutrition specialist can provide clients with individualized guidance. It takes into account their training program. It also considers how their body responds to protein and carbs.
At the same time, this professional can help with more than just nutrient timing. They can offer advice on calorie intake, how to create a balanced meal, and more. You can offer this advice yourself by becoming a certified nutrition coach.
Great personal trainers know you can't out-exercise a bad diet. This means clients need nutrition advice. Get started with ISSA! Through ISSA's Nutritionist certification course, you’ll learn all about food and food habits — so you can make the smart recommendations your clients need to crush those goals and live that dream.
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By becoming an ISSA Nutritionist, you'll learn the foundations of how food fuels the body, plus step by step methods for implementing a healthy eating plan into clients' lifestyles.
Farouk El-Sabban. “Sports Nutrition: An Evolved Multidisciplinary Field for Athletes”. EC Nutrition 2.1 (2015): 275-277.
Yang, F., Qiu, J., Yi, L., Liang, Y., & Liu, Y. (2018). OR-032 Effects of Protein Supplement Timing during 4-Week Resistance Training on Muscle Hypertrophy in Males. Exercise Biochemistry Review, 1(2). https://doi.org/10.14428/ebr.v1i2.9603
Pihoker, A., Peterjohn, A., Trexler, E., Hirsch, K., Blue, M., & Anderson, K. et al. (2019). The effects of nutrient timing on training adaptations in resistance-trained females. Journal Of Science And Medicine In Sport, 22(4), 472-477. https://doi.org/10.1016/j.jsams.2018.09.236
Smith, H., & Betts, J. (2022). Nutrient timing and metabolic regulation. The Journal Of Physiology, 600(6), 1299-1312. https://doi.org/10.1113/jp280756
Escobar, K., McLain, T., & Kerksick, C. (2015). Protein Applications in Sports Nutrition—Part II. Strength & Conditioning Journal, 37(3), 22-34. https://doi.org/10.1519/ssc.0000000000000138
Kafkas, A., & Kafkas, M. (2019). Resistance Training: Nutrient Timing in Terms of Protein Consumption. Journal Of Athletic Performance And Nutrition, 6(2), 13-21. doi:10.31131/japn.v6i2.94
Stecker, R., Harty, P., Jagim, A., Candow, D., & Kerksick, C. (2019). Timing of ergogenic aids and micronutrients on muscle and exercise performance. Journal Of The International Society Of Sports Nutrition, 16(1). https://doi.org/10.1186/s12970-019-0304-9
Kume, W., Yasuda, J., & Hashimoto, T. (2020). Acute Effect of the Timing of Resistance Exercise and Nutrient Intake on Muscle Protein Breakdown. Nutrients, 12(4), 1177. https://doi.org/10.3390/nu12041177
Morton, R., McGlory, C., & Phillips, S. (2015). Nutritional interventions to augment resistance training-induced skeletal muscle hypertrophy. Frontiers In Physiology, 6. https://doi.org/10.3389/fphys.2015.00245
Casazza, G., Tovar, A., Richardson, C., Cortez, A., & Davis, B. (2018). Energy Availability, Macronutrient Intake, and Nutritional Supplementation for Improving Exercise Performance in Endurance Athletes. Current Sports Medicine Reports, 17(6), 215-223. https://doi.org/10.1249/jsr.0000000000000494
Hull, M., Neddo, J., Jagim, A., Oliver, J., Greenwood, M., & Jones, M. (2017). Availability of a sports dietitian may lead to improved performance and recovery of NCAA division I baseball athletes. Journal Of The International Society Of Sports Nutrition, 14(1). https://doi.org/10.1186/s12970-017-0187-6