How Should Your Diet Change From Training Days To Race Day?

How Should Your Diet Change From Training Days To Race Day?

When it comes to competing in endurance races, your race day nutrition strategy is arguably equally as important as your training day strategy. Below are some tips that can help you get the adjustment right come the starting line and let your nutrition fuel your performance for a great finishing time:

The days prior to race day should be used to carbohydrate load. During training, many athletes manipulate carbohydrates to elicit further training adaptation. However, when it comes to race day, your aim should be to increase your carbohydrate intake significantly in the 24–36 hours prior to the event to between 7–10g per kg of body weight1. For example, an 80kg athlete would need between 560g–800g of carbohydrates. To achieve such high amounts, focus on low-fibre sources to aid digestion and reduce satiety. Examples include basmati rice, pasta, white bread, cereal, or sports drinks.

Caffeine

Caffeine has been shown to improve endurance performance and should be consumed 60 minutes prior to the event. The dosage depends on individual preference and tolerance but should always be tested during training first. Doses between 3mg–6mg per kg of body weight have been shown to aid endurance performance2. This means a 60kg athlete should consume between 120mg–360mg of caffeine. Good sources include coffee, caffeine tablets, or pre-workout energy drinks. The table below shows average caffeine content from common sources:

Snacking

Snacks are a convenient way of increasing carbohydrate intake during both the loading phase and the event. Options such as sports drinks, bananas, energy gels, dried fruit, or sugary sweets are all effective. During the race, aim to consume up to 60g of carbohydrates per hour to support performance. Examples include two large bananas, one litre of sports drink, 90g of dried fruit, or 60g of jelly beans. Snacking during the event can sometimes cause stomach upset, so test all race-day strategies in training. If you experience continued issues, try mouth-rinsing a sports drink for five seconds — this has been shown to improve performance even without swallowing.

Hydration

You should aim to start the race fully hydrated, as beginning dehydrated can impair performance. As a guide, slowly drink 5–10ml of fluid per kg of body weight (e.g., 350–700ml for a 70kg athlete) 2–4 hours before the event. It’s also important to maintain fluid intake during the race, as even a 2% loss can affect endurance3. As a general guideline, drink 100–200ml every 15 minutes, adjusted to your tolerance and experience. Sports drinks containing electrolytes can help replace lost fluid and provide carbohydrates during longer efforts.

Post-Race Nutrition

Once the race is completed, your focus should switch to recovery. Eating a meal that combines protein and carbohydrates is optimal. Aim to consume 0.4g/kg of protein and 0.8–1.2g/kg of carbohydrate after the race. The combination of both has been shown to best support recovery4. For example, a 70kg athlete should consume about 28g of protein and 56–84g of carbohydrates. You can calculate your specific protein needs with our protein calculator. Examples of balanced recovery meals are shown below:

 

It’s important to remember that nutrition is highly individual. What works for one athlete might not work for another. That’s why it’s crucial to test all race-day strategies in training. By finding what works best for you ahead of time, you’ll feel confident and prepared on race day — one less thing to worry about. Control the controllable!

If you’re a PT and want to expand your nutritional knowledge, enrol in the Optimum Nutrition for Health and Performance course. It’s ten one-hour modules designed to help you empower your clients with evidence-based advice. Sign up today.

NOTE: The following information is for educational purposes only and does not reflect the opinion of Glanbia Performance Nutrition, nor is it intended for product marketing purposes.

References

  1. Bussau, V.A. et al. (2002). Carbohydrate loading in human muscle: an improved 1-day protocol. European Journal of Applied Physiology, 87(3), pp.290-295.
  2. Desbrow, B. et al. (2012). The effects of different doses of caffeine on endurance cycling time trial performance. Journal of Sports Sciences, 30(2), pp.115-120.
  3. Cheuvront, S.N. & Sawka, M.N. (2005). Hydration assessment of athletes. Sports Sci Exchange, 18(2), pp.1-6.
  4. Zawadzki, K.M. et al. (1992). Carbohydrate-protein complex increases the rate of muscle glycogen storage after exercise. Journal of Applied Physiology, 72(5), pp.1854-1859.