Adequate nutrition is important for long-distance runners. Poor nutrition can lead to issues such as poor concentration, early fatigue and nutritional deficiencies. We will examine some of the fundamentals of sports nutrition, namely carbohydrates, protein and hydration, and how they impact your performance.
FUEL YOUR ACTIVITY
Carbohydrate is the primary source of fuel for the body. For runners, insufficient carbohydrate intake can result in fatigue, which would reduce their ability to train. It would also impair sports performance and can affect one's immunity in the long run.
Carbohydrates can be categorised in three main categories, namely complex carbohydrates, simple carbohydrates and dietary fibre. Knowledge on these different types can help one plan suitable meals on training days:
• Complex carbohydrates (rice, noodles, bread, pasta and potatoes): Digested and absorbed slower than simple sugars
• Simple carbohydrates (table sugar, honey, candies, sweets, gummies, etc): Easily digested and absorbed by the body
• Dietary fibre (non-starchy vegetables, fruits with edible skins and seeds and wholemeal food products): Foods high in dietary fibre take a longer time to digest
Your carbohydrate needs depend on the type of activity, the intensity, frequency and duration of the specific activity. As your physical activity level changes from day to day, you probably need to eat more during your training days compared to non-training days, particularly if you do not intend to lose weight.
So a healthy adult who weighs 60kg and undergoes moderate to high intensity training for about two to three hours a session, five to six times a week, would require approximately 300-480g of carbohydrates per day. On average, one bowl of rice, three slices of bread or 11/2 medium-sized potatoes is equivalent to 45g of carbohydrates.
REPAIR AND RECOVER
Dietary protein is important to manufacture body protein, which has important structural and functional roles. Protein requirements of athletes vary, depending on the type and the intensity of exercise.
Long-distance runners who undergo heavy training require extra protein for the energy needed in their training. It also assists in the repair and recovery process after the activity as heavy training has shown to increase protein breakdown.
Examples of non-vegetarian protein sources are meat, fish, egg and seafood, while soy and soy products, nuts, legumes, lentils and dairy products are good vegetarian protein sources.
A healthy adult who weighs 60kg, undergoes moderate amount of intensity training would require approximately 60-90g of protein per day. On average, a glass of milk, an egg or a matchbox-size of meat is equivalent to 10g of protein.
Ensuring that you are well-hydrated is important as it prevents heat-related injuries and impaired exercise performance.
The amount of fluid required varies from person to person. One way to determine hydration status is to look at the colour of your urine. If it is pale yellow, you are likely well hydrated; if it is darker than usual, it is an indication that you are not hydrated adequately.
Develop a fluid intake plan for long training sessions. Begin rehydrating every five to 20 minutes, consuming 150-200ml of fluids.
FINE TUNING YOUR FOOD INTAKE
Before training: For a 60kg healthy adult whose training lasts more than one hour, it is recommended to consume 60-240g of carbohydrates one to four hours before embarking on the activity.
Foods higher in fat, protein and fibre tend to take longer to digest. Large quantities of food take longer to digest. Hence, if you are only able to eat one hour before the activity, then a low-fibre, low-fat small meal such as breakfast cereal might suit you. It is also recommended not to try new food items on race day.
During training: Consuming carbohydrates during training would help reduce fatigue and provide additional energy. However, this has little benefits for low intensity exercise sessions lasting less than 60 minutes, especially if you ate three to four hours before the training and weight loss is intended.
The beneficial amount of carbohydrate intake is dependent on the duration and intensity of the training. For training sessions which last an hour, an individual may reap the benefit of carbohydrates from drinking 500ml of sports drink as it contains approximately 30g of carbohydrates.
Runners also need to eat and drink adequately to refuel, repair and rehydrate our body to prepare it for the next training session. Failing to do so can compromise performance in subsequent sessions as the body needs to replenish carbohydrate stores and rebuild muscle protein. Food that contains adequate carbohydrates and protein include chocolate milk, meat buns and sandwiches.
A good grasp of basic sports nutrition principles can help one optimise training and performance. It is recommended that one should consult a sports dietitian to translate the above basic principles into practical and tailored advice for you.
• Kejendran Mangaikarasu is a senior dietitian at the dietetics department in National University Hospital. He is part of a multi-disciplinary team at the NUH Sports Centre and has interest in critical care and sports nutrition