In the third and final edition of our 'Carbohydrates and Performance' series, we arm you with the best practices for pre-, intra-, and post-exercise fuelling.
If you have followed along during this series, we have explained why carbohydrates are the optimal fuel for athletic performance, and how to go about calculating an evidence-based daily carbohydrate intake for your own activity level. To cap things off, we’re going to delve into the literature on the best way to fuel before and after a bout of exercise, be it training, or a match.
Fuelling Optimally vs. Suboptimally
We have data from as early as 1973 showing footballers that played a game with low muscle glycogen, or low levels of fuel in their system, covered 2.3 kilometres less, and spent almost double the time walking, and almost half the time sprinting, compared to those with normal pre-game fuel stores (1). Similarly, in cyclists fed a high-carbohydrate meal (312 grams of carbs) 4 hours prior to an exercise test, performance time was increased by 15%, compared to cyclists who were fed nothing prior (2).
Likewise, eating a carbohydrate-rich meal 3 hours before exercise improved running performance in active females, compared to not eating the meal (3), and carbohydrate-rich meals eaten as close as 45 minutes (4), and 60 minutes (5), prior to exercise have shown improved endurance performance compared to not eating. If it is not already apparent, there’s a trend emerging here…
These findings have been consistently repeated over the last half century, and is why established sports nutrition bodies such as the American College of Sports Medicine and International Society of Sports Nutrition firmly endorse eating carbohydrates before a bout of moderate- to high-intensity exercise (6, 7).
Evidence-Based Recommendations
The following recommendations come from the position statement of the Academy of Nutrition and Dietetics, Dietitians of Canada, and American College of Sports Medicine on nutrition and athletic performance (6).
Before Exercise:
1). If eating 3–4 hours before exercise:
Consume a meal containing 3–4 grams per kilogram of body weight (g/kg) of carbohydrates
2). If eating 1–2 hours before exercise:
Consume a meal containing 1–2 g/kg of carbohydrates
3). 5–10 minutes before exercise:
If possible, drink 150–350 millilitres (mL) (e.g., water or Lucozade Sport)
It is important to test these protocols in training before you put them into practice on match day. This is because this quantity of carbohydrates (and food) may be more than what you’re used to. So, it may take a bit of time for your body, particularly your stomach, to adapt to this regimen. If you’re struggling to eat quite this much, try to swap solid foods (e.g., oats) for liquids (e.g., fruit juice).
During Exercise:
Consuming carbohydrates during exercise provides further benefits for physical performance. Take a look at Figure 1, below. Cyclists who ate carbohydrates before and during an exercise test performed at a higher average power output and lasted longer before exhaustion, compared to those eating nothing, those eating carbohydrates before exercise only, or those eating carbohydrates during exercise only (8).
Recommendations:
Consume 30–60 g/hr for events lasting 1–2.5 hours (e.g., a match).
Figure 1. Cyclists eating carbs before and during exercise (C/C) performed at a higher average power output, and for longer, compared to those who ate nothing before or during (P/P), those who ate carbs before exercise only (C/P), and those who ate carbs during exercise only (P/C) (8).
Post Exercise:
Naturally, fuelling up after a training session or match is important. After such a bout of exercise, our glycogen stores are depleted, and need to be stocked back up. This is particularly important if you will play a match soon afterwards, e.g., in a tournament structure. Ensuring you fuel properly after exercise helps to facilitate recovery, which is a fundamental component of the Training-Adaptation Cycle (Figure 2).
Recommendations:
Consume 0.7 g/kg of carbs within the first 20–30 minutes of exercise
Consume a mixed meal, containing carbs (1–1.2 g/kg), protein, and fat within 2 hours of exercise
Figure 2. Training-Adaptation Cycle
Putting Everything Together
Let’s put these recommendations into practice, using an 80 kg individual as an example. For this player, this is match day.
Pre-Match Meal (2 hours before)
80 g oats w/ 300 mL milk/soy milk + apple + banana + 250 mL orange juice
This provides ~137g carbs
Note: increase portions if eating 3–4 hours before
5–10 Minutes Before Match
150–350 mL of Lucozade Sport (or water)
Half-Time
Banana and/or some Lucozade Sport (or similar sports drink)
Post-Match
Within 20–30 minutes: apple and/or banana
Within 2 hours: a mixed meal
Example: pasta/rice dinner with vegetables, lean meat, and/or plant-based protein such as lentils and/or tofu
Summary
If you take these recommendations on board, combined with what you have learned in Part 1 and Part 2 of this series, you’re in the position to maximise athletic performance. Of course, there are other dietary factors that can influence performance, e.g., supplements such as caffeine or creatine, etc., but when it comes to the big-picture stuff, nailing your carbohydrate intake is the most important lever you can pull.
Why not put these recommendations into practice before your next Training121 session? Get in contact with us here: [email protected] to level up on the pitch, too.
Have a good weekend!
Patrick Elliott, BSc, MPH
Health and Nutrition Science Communication Officer at Training121
Instagram: @just.health.info
Twitter: @PatrickElliott0
Health Disclaimer: this article is for informational and educational purposes only, and is not a substitute for professional advice. For health advice, speak to a physician or other qualified health-care professional, and for nutrition advice, speak to a qualified nutrition professional (e.g., registered dietitian). The use of information on this site is solely at your own risk.
References
(1) Saltin B. Metabolic fundamentals in exercise. Med Sci Sports. 1973;5(3):137-46. Available at: https://journals.lww.com/acsm-msse/Abstract/1973/23000/Metabolic_fundamentals_in_exercise.10.aspx
(2) Sherman WM, Brodowicz G, Wright DA, Allen WK, Simonsen J, Dernbach A. Effects of 4 h preexercise carbohydrate feedings on cycling performance. Med Sci Sports Exerc. 1989;21(5):598-604. Available at: https://journals.lww.com/acsm-msse/Abstract/1989/10000/Effects_of_4_h_preexercise_carbohydrate_feedings.17.aspx
(3) Maffucci DM, McMurray RG. Towards optimizing the timing of the pre-exercise meal. Int J Sport Nutr Exerc Metab. 2000;10(2):103-13. Available at: https://pubmed.ncbi.nlm.nih.gov/10861332/
(4) Kirwan JP, Cyr-Campbell D, Campbell WW, Scheiber J, Evans WJ. Effects of moderate and high glycemic index meals on metabolism and exercise performance. Metabolism. 2001;50(7):849-55. Available at: https://pubmed.ncbi.nlm.nih.gov/11436193/
(5) Thomas DE, Brotherhood JR, Brand JC. Carbohydrate feeding before exercise: effect of glycemic index. Int J Sports Med. 1991;12(2):180-6. Available at: https://pubmed.ncbi.nlm.nih.gov/1860741/
(6) Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. J Acad Nutr Diet. 2016;116(3):501-28. Available at: https://journals.lww.com/acsm-msse/Fulltext/2016/03000/Nutrition_and_Athletic_Performance.25.aspx
(7) Kerksick CM, Wilborn CD, Roberts MD, Smith-Ryan A, Kleiner SM, Jäger R, Collins R, Cooke M, Davis JN, Galvan E, Greenwood M, Lowery LM, Wildman R, Antonio J, Kreider RB. ISSN exercise & sports nutrition review update: research & recommendations. J Int Soc Sports Nutr. 2018;15(1):38. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6090881/
(8) Wright DA, Sherman WM, Dernbach AR. Carbohydrate feedings before, during, or in combination improve cycling endurance performance. J Appl Physiol (1985). 1991;71(3):1082-8. Available at: https://pubmed.ncbi.nlm.nih.gov/1757304/
Technical Terms
Glycogen: The stored version of carbohydrates, or glucose. When we eat carbohydrates, most is stored as glycogen in our muscles and liver.
Training-Adaptation Cycle: A term used to represent how athletes adapt to training. Put simply, training exposes us to physical challenges that can produce physical adaptations down the line. The steps between “training” and “adaptation” are mediated by “fatigue” and “recovery”, that is, our bodies become fatigued after training, and must recover (stronger) to adapt from the training. This can be an acute process, where we adapt after a single bout of training, or can be chronic, where we adapt after a period of training.
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