What are carbohydrates?
Carbohydrate foods are your body’s go to source of energy when you're in training. Your body breaks them down into glucose to give you energy. This glucose can be used by your body straight away, or stored in your liver as glycogen, to give you energy later.
These glycogen stores are limited, so when you are exercising regularly it is important to keep these stores topped up by eating regular carbohydrate foods over the day. This helps ensure you have enough energy to support your exercise, as well as improve performance.
How much carbohydrate do I need?
You should try to include carbohydrates in every meal, especially in the run up to your challenge – this will keep your muscle energy (glycogen) levels topped up.
We recommend using your hand as a guide to portion size – portions of carbohydrates should be slightly bigger than the palm of your hand.
Check out our full BHF portion size guide.
Our tips for eating the right carbohydrates when exercising
Choose those that release their energy slowly, such as:
- Wholegrain breads, rice and pasta
- Cereals
- Sweet potatoes
- Pulses (like beans, peas and lentils)
- Fruit and veg.
Look at your bread, pasta, and grain selections and see if you can swap white refined versions for wholegrain ones. An easy way to start is to try wholegrain breakfast cereal and wholegrain bread. These contain more fibre than the white alternatives, and provide you with a steady stream of energy throughout the day.
As a guide, half of your plate should be carbohydrate foods. The rest should be protein, vegetables, or salad.
Eating carbohydrates for gluten-free athletes
People with coeliac disease absolutely need to avoid gluten as it damages their intestines and their ability to absorb nutrients.
If you are following a gluten-free diet it's still easy to meet your carbohydrate requirements – there are many naturally gluten free carbohydrate foods you can choose from to keep you fuelled:
- beans, peas and pulses
- lentils
- rice
- corn
- quinoa
- potato, sweet potato
- pumpkin, squash
- millet
- fruit.
Should I avoid gluten if I experience stomach issues while exercising?
Gastrointestinal issues (GI issues) – runners trots, bloating or stomach pain – can disrupt training and cause anxiety and many people avoid gluten as a result. However, it's important to recognize that GI issues can be complex and they could be caused by gluten, or something else.
These tips may help before you choose to remove gluten from your diet:
- Avoid high-fibre foods in the day before competition or before strenuous workouts (but keep fibre in your regular training diet).
- Avoid highly concentrated carbohydrate drinks (>10% carbohydrate) such as soft drinks, fruit juice, energy drinks. Standard sports drinks with 4-8% carbohydrates are less likely to cause stomach upset.
- Avoid dehydration, which can make stomach symptoms worse. Start your race (or training) well hydrated.
- Avoid eating too close to exercise as there won’t be enough time to digest the food eaten. Aim to eat 2-4 hours before exercise.
Energy gels and sport drinks
You don't need to use energy gels for your challenge, if it is less than an hour. If your challenge will take longer than an hour you will need to eat extra carbohydrates during the event.
What do I eat when exercising longer than an hour?
Our bodies only store enough glycogen for around 90 minutes of exercising. You need to provide additional fuel by eating or drinking foods containing carbohydrates for a longer exercise session.
As a guide, you should aim for 30 to 60g of carbohydrate per hour. You can get this with:
- Sports drinks: 500ml isotonic sports drink
- Gels: 1-2 gels
- Chews: If you find gels too sweet and sickly, blocks are an alternative. You can suck each block for around two 2 to three 3 minutes. Each block provides around 40-45g carbohydrate.
- Energy bars: Best for those longer events like ultramarathons, where taking in too many high-sugar carbohydrate drinks or gels gets a bit much and could give you an upset stomach. They tend to contain protein, slower-release carbohydrates and fats to provide a more energy-dense alternative.
- Food: Banana, dates (2x medjool dates), jelly babies ( x6), dried apricots (x4), handful raisins, honey sandwich.
If you’re taking part in a half marathon, sport energy drinks are an easy option. –Iin one 500ml bottle you should have enough energy to keep you topped up.
For a marathon, gels or chews, are useful as they are light and portable. For ultramarathons and longer runs, choose a mix of energy bars and natural foods. This way hopefully you’ll avoid an upset tummy.
Our golden rule is don’t experiment on event day.! Practice and try out the specific products or foods you are thinking about using. You might not get on with certain brands or product.
