You’ve done all the training and competition day is creeping up. You might get your kit ready, read the competition briefing, and settle down ahead of the big day.
What about your nutrition? What you eat in the build-up to competition – be it on the day, the day before, or the entire week – impacts your performance potential.
Carbohydrates for Performance
Consuming carbohydrate before, during, and after exercise increases carbohydrate availability. High carbohydrate availability maintains sufficient amounts of carbohydrate for the muscle and central nervous system to use as a substrate during exercise (1). Replenished muscle glycogen, following carbohydrate consumption, provides athletes with adequate stores to match the rough energy cost of the activity demands. A high carbohydrate diet remains the best choice for optimal performance, particularly at the elite level (2).
Think about the three T’s of carbohydrate – total, timing and type. But what total do you need, when, and what? Below are evidence-informed guidelines on acute carbohydrate intake for optimal performance.
Acute fuelling strategies (5).
Notice how, as exercise duration and/or intensity increases, so does the recommended required carbohydrate. The more you do, the more energy you need through such fuelling strategies.
This is what is meant by ‘energy for effort’, sometimes touted ‘fuel for the work required’. For exercise > 1 hour, 1-4 g/kg is recommended 1-4 hours before competition.
Practical needs, individual preferences, and an overall individualised approach (what works for YOU) should be considered.
For example, an Olympic diver may only have a handful of dives to perform, with hours in between each dive. They may require 6-7 g/kg/day for optimal performance, with small snacks of 1-2 g/kg carbohydrate throughout the day.
A marathon runner may want to practise carbohydrate loading, eating 10-12 g/kg/day in the few days before the event, and in-race consumption of 30-60 g carbohydrate per hour.
Carbohydrate loading is not necessary for every athlete; only those exercising >90 minutes, during which higher muscle glycogen stores could increase performance by 2-3% (3). This is where carbohydrate periodisation comes in
Following the idea of ‘fuel for the work required’, carbohydrate periodisation encompasses the necessary fluctuations in daily carbohydrate intake dependent on your activity level.
For example, a “sleep-low, train-high” strategy has been shown to improve performance (4). This is often used with a Red, Amber, Green (RAG) system. Red being lower carbohydrate intake, amber medium, and green high.
Athletes can continuously move on this scale, from lower intake (red) on rest days to much higher intake (green) if you train hard or have an intense competition. This gives you a method of ensuring that you don’t over- or under-fuel and potentially decrease performance.
Not that red does NOT mean zero-carb, rather, it indicates that smaller amounts of carbohydrate are required, and vice versa. In the example, you can see how rest days include less and the closer you get to training or competition, the more carbohydrates are required for optimal performance and recovery.
Table 1. An example of nutritional periodisation using the RAG system.
Carbohydrates are Great – What About the Rest?
The principles of a nutritionally balanced diet to maintain energy balance (i.e. energy intake = expenditure) remain. Athletes should aim to meet the recommended daily intakes for all macronutrients and micronutrients – as should everybody.
Dietary protein stimulates muscle protein synthesis and fat is involved in vitamin absorption. With specific reference to iron, calcium, and vitamin D, amongst others, athletes should aim to for adequate micronutrient intake for their health and performance benefits (6).
Iron plays a role in red blood cell production and immunity, and calcium and vitamin D go hand-in-hand (as seen in the previous article).
With the right total, timing, and type of carbohydrates, with your individual needs, competition demands, and preferences in mind; you can master a nutritional strategy that suits you and could improve performance on the big day.
About the Author: Liam Oliver, BSc (Hons) Sport and Exercise Science
University and Performance Nutritionist at British Diving.
Liam is aiming to complete a Masters course in Sports Nutrition and become SENr-accredited.
Twitter - @liam_oliver12
Refuel like a Pro with PROTEEN
Kick start muscle protein re-synthesis and reap the benefits of the added vitamins and minerals including the ever important Iron, Vitamin D3 and Calcium.
Get the best of both worlds - PROTEEN® utilises a unique double-source Carb blend featuring100% gluten free oat-flour. This means you get a balance of fast acting and slow release carbs, ensuring you feel fuller for longer, whilst reaping the benefits of rapid energy release.
1. Burke, Louise M. et al. (2011). Carbohydrates for training and competition. Journal of Sports Sciences, 29, 17-27.
2. Helge, J., W. (2017). A high carbohydrate diet remains the evidence based choice for elite athletes to optimise performance. The journal of physiology, 595, (9), 2775 DOI: 10.1113/JP273830
3. Hawley, J (1997). Carbohydrate Loading And Exercise Performance: An Update. Sports Medicine, 24, 73-81
4. Enhanced Endurance Performance by Periodization of Carbohydrate Intake: “Sleep Low” Strategy Marquet, M et al. (2016). Medicine & Science in Sports & Exercise, 48 (4), 663-672
5. Thomas, T; Erdman, K; Burke, L (2016). American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance. Medicine and science in sports and exercise, 48 (3), 543-68.
6. Flavia Meyer , Helen O'Connor & Susan M. Shirreffs (2007) Nutrition for the young athlete, Journal of Sports Sciences, 25:S1, S73-S82, DOI: 10.1080/02640410701607338