Carb and Fluid Intake for Endurance Sport

Supplement Advice: Carb and Fluid Intake for Endurance Sport
It's touted by many sports scientists that it takes just a 1% fluid loss to impair your performance. That works out around 700ml of sweat loss during endurance activities for a 70kg bodyweight. Some studies have shown that for every 1% of fluid lost, your heart rate can increase by between 5pm to 8bpm, which can be quite a significant increase when engaged in long duration events or training. A 5% loss can result in an decrease of performance of up to 30%. If you are engaging in endurance events, training, or sports for periods longer than 60 minutes, your performance can be improved through the use of carbohydrates, electrolytes, and fluid, before, during and after exercise.
Whether you are on a training run, playing sport, or competing in an endurance event you should look to consume around 0.7 g carbohydrates/kg body weight/h (approximately 30-60 g/h) as this has been shown unequivocally to extend endurance performance. For most people a carbohydrate intake of around 60 gram of carbs per hour is ideal for more prolonged events or training (2–3 h). For ultra-endurance and Ironman events, the recommendation is even higher at approximately 90 grams per hour.

Consuming carbohydrates during exercise or training is even more important if you haven't carb loaded pre-event, or haven't had a pre-exercise meal which can occur if training or taking part in events in the early morning. Ideally your carbohydrate and calorie intake should begin shortly after the onset of activity, consuming a given amount of carbohydrate in one hit after 2 hours of exercise is not as effective as have the same amount of carbs taken in smaller doses at more regular intervals throughout the 2 hours. Ideally any carbohydrates that you use should be consumed in small servings at regular time periods - every 15 to 30 minutes.

You want a combination of mainly long chain or sustained release carbs, and some short chain, fast and medium release carbs. Energy gels like Leppin Squeezy, Clif Shots or GU Energy Gel provide about 25 to 30 grams of carbs with added electrolytes - typically sodium and potassium which help replace the salts lost in your sweat to guard against muscle cramp and impaired performance - and so can be easily used every half hour to help extend your endurance.

Many energy gels use a blend of fast and slow release carbs, helping provide an instant energy boost as well as sustained energy. You can also choose to use wholefoods like energy bars, jelly babies, dates, and banana’s.

Before you decide, it’s a good idea to try out a few different things and find the one that best suits your training as well as your stomach. Make sure to always test energy gels and drinks during training runs rather than on race day to ensure it agrees with you. To ensure that the carbs are digested at the optimum rate you need to drink about 200 to 300 mls of water with every gel. This will help improve the rate of absorption in the gut and reduce gastrointestinal discomfort.

If you’re training or racing for less than 60 mins all you probably really need is water to help prevent dehydration. You should ensure you are adequately hydrated before training and aim to drink about 125-250 mls every 20 to 30 minutes.

On a daily basis for optimum performance and health, you should consume 3 to 4 litres of water per day outside of what you consume during training..

Remember caffeinated drinks - coffee, red bull, cola etc, and alcohol, have a diuretic action, and remove body water which can impair performance. If you are a regular coffee drinker, make sure to counter any fluid loss by drinking an extra glass of water per day for each caffeinated drink. Remember this also when training or taking part in events that any caffeine consumed during the activity can also increase your rate of water loss, and should be countered by subsequent increase in fluid intake.

Reference Links: