Pre- and Post-Workout Nutrition: A Practical Guide

Few topics in sports nutrition generate as much advice as what to eat around training. Some of it is solid physiology, some is leftover marketing from the era of the "30-minute anabolic window." Our editorial team summarizes what current guidelines from US and international sports nutrition bodies actually recommend, and how to apply it to real schedules.

Why the meals around training matter

Exercise is a stress that depletes fuel stores, breaks down some muscle protein and causes fluid loss. What you eat before training influences how much fuel is available and how you feel during the session. What you eat afterward influences how quickly glycogen is restored and how effectively muscle repairs and adapts.

The relative importance of these meals depends on the type of training, its duration and how often you train. A recreational lifter doing one session a day has much more flexibility than a triathlete with two sessions or a team-sport athlete playing back-to-back games.

The joint position statement of the Academy of Nutrition and Dietetics, Dietitians of Canada and the American College of Sports Medicine (2016) emphasizes that total daily intake of energy, carbohydrate and protein is the foundation. Timing adds a smaller, but sometimes meaningful, layer on top of that.

In other words, perfect workout nutrition cannot compensate for an inadequate overall diet. However, for people who already eat reasonably well, smart timing can improve training quality and recovery.

Before training: fuel without discomfort

The main purpose of a pre-workout meal is to top up liver and muscle glycogen, stabilize blood glucose and provide amino acids. A mixed meal containing carbohydrate, moderate protein and relatively little fat and fiber, eaten two to four hours before training, works well for most people.

Carbohydrate targets for this meal in endurance-oriented guidelines are often expressed as 1–4 g per kilogram of body weight, depending on how long before the session it is eaten and how demanding the session will be. For a 75 kg person doing a moderate gym workout, a lower amount is perfectly adequate.

If you only have 30–60 minutes, a smaller snack based on easily digested carbohydrates, such as a banana, a slice of toast with honey, or a sports drink, reduces the risk of stomach upset. Fat, fiber and large amounts of protein slow gastric emptying and are better kept for meals eaten further in advance.

Training fasted in the early morning is a personal choice. For short or low-intensity sessions it has little impact on performance. For long or very intense sessions, most athletes perform better with at least some carbohydrate beforehand.

During training: when it is worth eating

For sessions under about an hour, water is usually enough. For longer endurance sessions, consuming carbohydrate during exercise helps maintain intensity. Guidelines commonly suggest 30–60 g per hour for sessions of one to two and a half hours, and up to about 90 g per hour for longer events using mixtures of glucose and fructose.

Hydration needs vary widely with sweat rate, climate and clothing. A practical method is to weigh yourself before and after a typical session: each kilogram lost represents roughly a liter of fluid. Aim to keep losses below about 2% of body weight during most training.

Sodium becomes relevant in long sessions or hot conditions, particularly for heavy or "salty" sweaters. Sports drinks, electrolyte tablets or salty snacks all work. Drinking large amounts of plain water during very long events without sodium can, rarely, lead to dangerous hyponatremia.

Strength athletes rarely need intra-workout nutrition. Some evidence suggests that carbohydrate-containing drinks may help in very high-volume sessions, but for typical gym workouts the benefit is minimal.

After training: protein, carbs and the "window"

The idea of a narrow 30-minute anabolic window has been softened by research. A meta-analysis by Schoenfeld, Aragon and Krieger (2013) found that when total daily protein was matched, protein timing had little independent effect on muscle growth. The window is better thought of as several hours on either side of the workout.

Still, having a protein-rich meal within a couple of hours after training is a reasonable habit. The ISSN suggests roughly 0.25–0.4 g of high-quality protein per kilogram of body weight per meal, which for most adults means 20–40 g. That dose should contain around 2–3 g of leucine, which is easy to reach with dairy, eggs, meat or a whey shake.

Carbohydrate after training matters most when the next session is less than about eight hours away. In that case, intakes of around 1–1.2 g per kilogram per hour for the first few hours speed up glycogen restoration. Adding protein can help when carbohydrate intake is lower than this target.

For people training once a day with a full day to recover, regular meals across the day will restore glycogen without any special effort. Chocolate milk, a sandwich with lean meat, or rice with fish are all perfectly good recovery meals.

Putting it together in a weekly routine

Start with daily totals: protein in the range of about 1.4–2.0 g per kilogram for most active people, and carbohydrate scaled to training load, from about 3–5 g per kilogram on light days to 6–10 g per kilogram for heavy endurance training.

• Plan a carbohydrate-containing meal or snack before demanding sessions.
• Include 20–40 g of protein in the meal after training and in each main meal.
• Drink to limit fluid losses, adding sodium in long or hot sessions.
• Prioritize fast glycogen recovery only when sessions are close together.
• Test new foods and products in training, not on competition day.

Individual tolerance matters. Some athletes cannot eat solid food close to training; others feel weak without it. Keeping a simple log of what you ate and how the session went is a cheap way to find your own pattern.

Conclusions of the editorial team

Total daily intake is the foundation, and workout timing is a refinement. A carbohydrate-based meal before training and a protein-rich meal afterward cover the needs of most recreational athletes.

The strict 30-minute window is largely a myth for people training once a day, though rapid refueling still matters for multiple daily sessions and endurance events.

To go deeper, take a look at our articles on carbohydrate periodization, on electrolytes and hydration in hot weather, and on how much protein older athletes need.

References

1. Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine joint position statement: nutrition and athletic performance. Med Sci Sports Exerc. 2016;48(3):543–568.
2. Kerksick CM, Arent S, Schoenfeld BJ, et al. International Society of Sports Nutrition position stand: nutrient timing. J Int Soc Sports Nutr. 2017;14:33.
3. Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20.
4. Schoenfeld BJ, Aragon AA, Krieger JW. The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. J Int Soc Sports Nutr. 2013;10(1):53.
5. Burke LM, Hawley JA, Wong SH, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 2011;29(Suppl 1):S17–S27.
6. Aragon AA, Schoenfeld BJ. Nutrient timing revisited: is there a post-exercise anabolic window? J Int Soc Sports Nutr. 2013;10(1):5.