Nutrition and Hydration for Running

Key Points

Endurance is best described as the ability of the individual to maintain as high a work rate as possible for the duration of the event, whilst minimising the impact of fatigue.
Runners have significant nutritional requirements, whatever their chosen distance, due to the frequency and intensity of training and race day.
Carbohydrate is the fuel of choice for the brain, exercising muscle and central nervous system and is known to improve endurance performance
Sweating is the body’s primary mechanism of heat loss. However, if the fluid lost as sweat is not replaced, then dehydration occurs and body temperature will increase anyway.
As a result, appropriate sports nutrition strategies based on the provision of carbohydrate for energy and fluid for hydration is crucial to performance.
It is important that you practice any nutritional strategies during training before you use on race day, so you know what works for you.

Introduction

For events of 5 km or greater, endurance is the key determinant of success. Endurance is best described as the ability of the individual to maintain as high a work rate as possible for the duration of the event, whilst minimising the impact of fatigue. The ability to improve endurance is based on the quality and quantity of your training and nutritional strategy.

Runners have significant nutritional requirements, whatever their chosen distance, due to the frequency and intensity of training and race day. The two major causes of fatigue in running are a loss of fluid and a reduction in the body’s carbohydrate stores. As a result, appropriate sports nutrition strategies based on the provision of carbohydrate for energy and fluid for hydration is crucial to performance.

Carbohydrate

One of the most important aspects of the ‘athletic’ diet is to provide the muscle with substrates to fuel the training programme. Carbohydrate is the fuel of choice for the brain, exercising muscle and central nervous system and is known to improve endurance performance. Consequently sports nutrition guidelines are focused on strategies to enhance carbohydrate availability in the periods before, during and after exercise.

Fluid

Exercise results in the production of heat within the body, which unless removed, can lead to significant increases in body (core and skin) temperature. Sweating is the body’s primary mechanism of heat loss. However, if the fluid lost as sweat is not replaced, then dehydration occurs and body temperature will increase anyway. As a result, the consumption of fluid is critical to the safe and effective functioning of the body during exercise.

Top Tips for Training

The consumption of a balanced diet is essential for the supply of all vitamins and minerals necessary for the efficient functioning of the body. This should include approximately five pieces of fruit and vegetables a day.
Overall energy intake should increase proportionally given the training being completed. Ideally, 70% of the overall intake should be carbohydrate, 15% protein and 15% fat. However, this is better provided as body weight recommendations, i.e. grams of carbohydrate per kilogram body mass.
- On light training days, consume 5-7 g of carbohydrate per kg of body mass.
- On medium training days, consume 6-10 g of carbohydrate per kg of body mass.
- On heavy training days, consume 8-12 g of carbohydrate per kg of body mass.
Try to keep a diary of the training completed in addition to subjective feelings of fatigue. Therefore, if specific sessions are getting harder, it could be an indication that you are not getting enough carbohydrate in the diet and you may need to revise the quantities required.
Aim to maintain a well hydrated state throughout the day – drinking little and often so that your urine colour remains pale. Water is suitable during the day whilst the use of sports drinks and recovery powders are preferred immediately before, during and after running.

Before Training

Consume 5-7 ml of fluid per kg of body mass, ideally a sports drink, at least 4 h before the exercise. This is approximately 350-500 ml.
Consume a further 3-5 ml of fluid per kg of body mass 2 hours before exercise (200-350ml)
Depending on the time of your run, ensure suitable carbohydrate intake in the hours before exercise. Ideally this would be 100-150 g of carbohydrate 2-3 hours before starting. If you run early in the morning, use a blend of sports drinks and energy bars to prevent bloating.

During Training (> 60 Min or < 60 Min at a High Intensity)

Consume fluid at regular intervals throughout and at a volume that matches your sweat rate. This should be based on the calculation of sweat rate from body mass loss.
If you cannot weigh yourself before and after, it is recommended that you try and consume approximately 125-150 ml of a sport drink every 15-20 min.
Consume 30-60 grams of carbohydrate per hour. This is best achieved by combining Lucozade Sport and the Lucozade Sport Gel.

During Training (< 60 Min at a Low to Moderate Intensity)

Consume fluid at regular intervals throughout and at a volume that matches your sweat rate. This should be based on the calculation of sweat rate from body mass loss.
If you cannot weigh yourself before and after, it is recommended that you try and consume approximately 125-150 ml of a sport drink every 15-20 min.

NB Calculation of Sweat Rate: Sweat rate can be calculated by measuring body mass (nude) immediately before and immediately after training and adjusting for fluid intake. For example if you lost 0.5 kg in body mass and drank 500 ml during 60 min of running, then your sweat rate is approximately 1.0 litre per hour.

After Training

Consume approximately 150% of the fluid lost as sweat that was not replaced. For example if you lost 0.5 litres during a 60 min run, drink approximately 750 ml over the first 90 min followed by your normal drinking habits for the remainder of the day.
Consume 1.2 g of carbohydrate per kg of body mass within the first 60 min after running. Combine this with 15g of protein to help aid the recovery and regeneration of the muscles.

Top Tips For Race-Day

No matter what your event, the importance of preparing properly cannot be underestimated. Failure to do so will undoubtedly lead to poor performance no matter what you then do during the event. It is very important that you practice any nutritional strategies during training before you use on race day, so you know what works for you.

For both half and full marathons, your ability to maintain your chosen speed can only be maintained by drinking and consuming carbohydrate as advised above. However, for both 5 km and 10 km races, the provision of fuel is not so important. However, if you can consume some fluid during, that would be of benefit, especially in hot conditions.

Prepare you race day bag the night before, ensuring that it contains your sports drinks/powders, energy bars and carbohydrate gels. These are your ‘kit bag’ carbs, and will allow you to top up your energy stores and maintain hydration right up to the start. They will also provide you with an immediate source of energy for the recovery period up until you can eat a main meal.

Caffeine

Caffeine is a naturally occurring compound found in the leaves, nuts and seeds of various plants and enjoys widespread use around the world. It is commonly consumed in various forms including coffee, tea and soft drinks, providing ~ 30-100 milligrams (mg) of caffeine per serve. Caffeine is one of the most widely researched ergogenic (enhances athlete performance) aids with proven performance benefits in runners.

Many runners consume 2-3 mg of caffeine per kilogram of body mass (~ 150-250 mg) 60 min prior to the start of exercise to help reduce the feelings of fatigue and thus maintain there chosen speed (if not faster) for the duration of the event. Caffeine intake should be practiced during hard training sessions before race day.