Race week is a time for nerves and a time for excitement. You’ve done months of training, it's your A race, taper week is here. The training duration decreases, maybe some shorter intensity stuff, foam rollers make a permanent spot on the lounge room rug, race wheels on. All is set, except for nutrition. The forgotten component of endurance sports. Most are conscious of having a strategy of what they are eating on race day but the race week, that’s a strategic ones game. Some may be tempted to change their diet based on what pros are doing or talking about. Don’t do this. Race week nutrition can play a massive role in reducing gut issues on race day while ensuring you are adequately hydrated and fuelled. So what should we actually be eating during race week?
Slowly Increase Carbohydrates
As we enter into taper week we decrease our training load. This naturally increases our glycogen uptake (stored carbohydrates), as we use less carbohydrate for training but consume the same amount of carbohydrates and overall calories. So until around 3 days before our race we want to eat similar to our normal diet. This only works though if we are eating enough overall calories in general and not under eating. As a guide both males and females should be eating a baseline calorie intake of 45-60 calories per kilogram of fat-free mass per day (1).
The last 3-4 days before race day is where some changes need to occur. The recommendations for carbohydrate intake leading into endurance events should be different for males and females.
Women’s bodies fuel differently from men’s. Females rely on carbohydrates first, then fatty acids to fuel our training. Our bodies don’t respond the same way to deliberate attempts to stuff our body at pasta parties. Two consecutive studies have shown that men may be able to increase their muscle glycogen concentration by 23-41 percent while women may not be able to increase their storage at all, best case a potential increase of 17 percent (2,3).
In summary women burn more fat than men during endurance exercise, but also store less muscle glycogen in response to carb-loading than their male counterparts (4). Therefore females should only slightly increase their carbohydrate intake a few days before race day, males can be slightly more aggressive. However endurance athletes both male and female should be focusing more on eating enough, including carbohydrates, before, during, and after training on a regular basis rather than trying to cram carbs in the days or night before a race.
Reduce Fibre
Fibre is the insoluble carbohydrate part of food. It yields no calories or kilojoules as it is not absorbed by the body, but rather passes through the large hole in our body most commonly known as the digestive tract. Fibre is most commonly found in fruit, vegetables, grains, nuts and seeds (4). In day to day life fibre is essential for healthy bowel movements, producing healthy gut bacteria, eliminating unwanted cholesterol and assists us in the feeling of fullness and being satisfied. (5). Due to fibre's fermentation process in the gut, it often has a by-product of gas. Gas, fullness, large bowel movements are something we want to avoid on race day to help prevent unwanted toilet stops.
Usually on a day to day basis it is recommended we consume 20-25g of fibre per day (6). During race week I aim to get my athletes consuming less than 10g per day.
Snacks that are low in fibre but high in carbohydrates are; Em's Power Cookies - Power Bites, Clif Bar - Nut Butter Bar, Skratch Labs - Sports Crispy Rice Cakes, GU Energy - Stroopwafel.
Increase Available Hydration
Another common nutrition mistake leading into race day is drinking plain water. Plain water isn’t actually hydrating. We need a combination of sodium and water to hydrate the body. Over consuming plain water can actually dilute our blood plasma volume and cause water and salt to be excreted via our urine. This process can result in hyponatremia (low blood sodium concentration) (7).
When we become dehydrated (as defined by a body fluid deficit >2% of body mass) we put a strain on our cardiovascular system which makes exercise harder. Dehydration can decrease aerobic power by 6% (8). Being dehydrated will slow you down a lot faster than low energy will!
Be sure to have a water bottle on hand at all times during race week with a solution that contains water and electrolytes. This can be easily made by adding an electrolyte tablet to your water bottle such as SaltStick Electrolyte Drink Mix, Hammer Nutrition - Endurolytes Fizz, Science In Sport (SIS) - Go Hydro Tablets or Huma Gel - Hydration Drink Mix.
References
1. VAZQUEZ FRANCO, Mireya et al. Update on nutritional deficiencies in women athletes from the scientific literature. ALAN [online]. 2020, vol.70, n.3, pp.191-204. Epub 15-Nov-2021. ISSN 0004-0622. h[ps://doi.org/ 10.37527/2020.70.3.005. h[ps://www.alanrevista.org/ediciones/2020/3/art-5/
2. Tarnopolsky MA, Zawada C, Richmond LB, Carter S, Shearer J, Graham T, Phillips SM. Gender differences in carbohydrate loading are related to energy intake. J Appl Physiol (1985). 2001 Jul;91(1):225-30. doi: 10.1152/jappl.2001.91.1.225. PMID: 11408434.
3. Tarnopolsky MA. Gender differences in metabolism; nutrition and supplements. J Sci Med Sport. 2000 Sep;3(3):287-98. doi: 10.1016/s1440-2440(00)80038-9. PMID: 11101268.
4. Tarnopolsky MA, Atkinson SA, Phillips SM, MacDougall JD. Carbohydrate loading and metabolism during exercise in men and women. J Appl Physiol (1985). 1995 Apr;78(4):1360-8. doi: 10.1152/jappl.1995.78.4.1360. PMID: 7615443.
5. Reynolds A et al Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. Lancet 2019;393:434-445.
6. Barber TM, Kabisch S, Pfeiffer AFH, Weickert MO. The Health Benefits of Dietary Fibre. Nutrients. 2020 Oct 21;12(10):3209. doi: 10.3390/nu12103209. PMID: 33096647; PMCID: PMC7589116.
7. Biswas M, Davies JS. Hyponatraemia in clinical practice. Postgrad Med J. 2007 Jun;83(980):373-8. doi: 10.1136/pgmj.2006.056515. PMID: 17551067; PMCID: PMC2600061.
8. Fleming, J., and L.J. James (2014). Repeated familiarisation with hypohydration attenuates the performance decrement caused by hypohydration during treadmill running. Appl. Physiol. Nutr. Metab. 39:124-129.
