Consuming the right food and drink is important for everyone. However, fuelling your body correctly is essential if you regularly take part in sports. Your performance, recovery time and risk of injury can all be impacted by the food and drink you consume.

There are three main areas of nutrition that you should focus on in relation to exercise.

Carbohydrates

Carbohydrates are an essential source of fuel for the body. They are broken down by the body into glucose (sugar), which is the main source of energy for every cell in our bodies. They are particularly important during exercise, where the demand for energy is higher due to increased muscle contraction, higher breathing rate, elevated heart rate, and increased metabolism.

Any glucose that is not immediately needed by the body can be stored in the liver – this stored form of glucose is called glycogen. During exercise, your body uses glycogen to provide energy. Therefore, after exercising these stores need to be replenished. The International Society of Sports Nutrition (ISSN) recommends consuming 30-60g carbohydrates within 30 minutes of completing a session of physical activity.

If you are exercising for longer than an hour e.g. playing a football match, running a marathon, to maintain energy levels the ISSN recommends consuming 30-60g carbohydrates per hour.

Protein

Protein is essential for growth and repair of muscles. It also boosts glycogen storage, relieves post-exercise muscle soreness, and promotes muscle repair.

You should be consuming a portion of protein at every mealtime (see our article on Portion Sizes). Choose a variety of animal-based and plant-based proteins, such as pulses, lentils, and soy-based products. For animal-based proteins, such as meat and dairy, choose lower fat options to limit the amount of saturated fat you consume. If you only consume plant-based proteins, it’s important to vary the sources of protein in your diet to ensure that you are getting a range of amino acids (the building blocks of proteins).

In addition to the amount of protein, recent research has shown that the timing of consuming protein is important. The ISSN recommends eating a meal every 3-4 hours which contains 20-40g protein. As protein synthesis is increased in the two hours post-exercise, it is important to consume protein during this time.

To gain muscle, you need to be eating both carbohydrates and protein and doing some resistance training (also known as strength or weight training). Currently, there is a no evidence to show that protein supplements can improve sports performance. Excess protein cannot be stored by the body so it’s either stored as fat (particularly when it replaces carbohydrates in the diet), used as a source of energy, or excreted in urine.

Water

Doing exercise raises your body temperate; to cool down, your body produces sweat, of which water is the main component. Therefore, the more you sweat, the more water you need to drink to replace the lost fluids. This is especially important when exercising for long periods of time, or in warmer weather.

Not drinking enough water increases your risk of dehydration, which can lead to tiredness and impact your performance both mentally and physically.

You should make sure that you drink fluids before, during and after exercise. Water is best option for moderate and light intensity exercise, that lasts for up to an hour. If you are doing high intensity exercise, or being physically active for more than an hour, there may be some benefits to consuming drinks containing sugar and electrolytes which are lost through sweating.  Furthermore, sodium helps absorption of water into the body.

Homemade sports drinks (200 ml fruit squash containing sugar, not sweeteners, 800ml water and a pinch of salt) and skimmed or semi skimmed milk are good options. Ready-made sports drinks are often high in free sugars, which make then high in calories and increase the risk of tooth decay.

Note: energy drinks are not the same as sports drinks, as they contain a stimulant e.g., caffeine.

Supplements

Following a healthy, balanced diet should provide enough nutrients and energy for exercise. Supplements are usually only used when the diet is inadequate, or you have been diagnosed with a deficiency e.g., iron. However, research has shown that supplementation with creatine, a compound found in muscles, in combination with resistance training, can promote muscle growth.

If you are considering taking supplements to aid your sports performance, it’s advised to speak to a professional sports nutritionist or dietician.

Sources

Burke R, Piñero A, Coleman M, Mohan A, Sapuppo M, Augustin F, Aragon AA, Candow DG, Forbes SC, Swinton P, Schoenfeld BJ. The Effects of Creatine Supplementation Combined with Resistance Training on Regional Measures of Muscle Hypertrophy: A Systematic Review with Meta-Analysis. Nutrients. 2023 Apr 28;15(9):2116

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