Sports Nutrition
Never underestimate the importance of carbohydrate. Often people exercising are trying to loose weight therefore they put off using energy drinks because they think they are high in calories, but it is important to remember that quality exercise depends upon carbohydrate energy. When carbohydrate energy supply is compromised exercise intensity has to be reduced. This means that fewer calories are burned for each hour of exercise. Notice that in this typical example for a trained cyclist, maximum fat burning of about 40g per hour requires over twice as much carbohydrate. Even at low intensities like this, carbohydrate usage is faster than optimal replacement. Exercising with low carbohydrate supply also increases muscle protein breakdown and the risk of infections.
There have been many studies that have shown endurance performance correlates with carbohydrates stores, and that fatigue occurs when these stores are used up. Most athletes are aware of glycogen depletion and describe it as “bonk”. Since it is impossible to burn fat aerobically, high intensity workouts deplete the body of carbohydrate rapidly. It is possible to deplete carbohydrate stores with as little as 20 minutes of interval training. So carbohydrate is important for both power and endurance athletes. This is why it is important to have a diet that is high in complex carbohydrate and why many athletes have adopted the strategy of carbo loading. Recent work has shown that it is possible for trained athletes to achieve an increased carbohydrate store by tapering training and increasing carbohydrate intake in the days preceding competition. The only major problem with this is physically eating the required quantity of carbohydrate. This is usually more than that with which athlete feels comfortable. 600g per 24 hours is required e.g 3 kg of potatoes! Science in Sport have formulated PSP22 which has been recommended as a more palatable way of ingesting the required amount of carbohydrate without eating too much fat or protein. Depletion loading regimes, where by athletes deprives them selves of carbohydrate stores, before “super-compensating” with a high carbohydrate diet are no longer recommended. Latest research has shown that it is much more important to keep blood sugar levels high during exercise with a regular supply of carbohydrate energy drinks and gels, in order to improve performance. Energy drinks and gels provided during exercise help to maintain blood sugar levels, which helps access more of the scarbohydrate stored in the muscle. Once blood glucose levels start to fall, fatigue sets in and performance suffers.
Pre event feeding
Conventional advice is that the pre event meal should be taken 3 hours before competing. It should be relatively light but high in carbohydrates and low in fat. Science in Sport PSP22 energy and GO gels can be useful in this pre event meal to increase the carbohydrate content without increasing the bulkiness of the meal. Eating anything within an hour before an event has, in the past, been considered detrimental to performance due to the possible insulin response. There is also evidence that it may be beneficial to take a small amount of strong solution 5-10 minutes before competition. This is certainly recommended once into warm-up, especially if consuming carbohydrate during the event is not possible. Science in Sport PSP22 and Go Gels are particularly useful for consuming high concentrations of energy, since they are easily tolerated due to their unique carbohydrate structure. People vary in their response to pre event feeding and, as with any nutritional strategy, it is worth experimenting with different combinations during training, to work out which strategy best suits the individual. Many sports people prefer to sip on energy drinks from the pre event meal right through to the warm up and into the event. If it is very hot or humid a weaker carbo/ electrolyte solution is appropriate.
How sports drinks improve performance
Some studies have shown that many people do not drink anything from the time they start their warm up until the time they start to race. This means that when they are on the start line their hydration and energy supply is already compromised. Improving sports performance in these situations maybe as simple as taking 3-400ml of energy drinks e.g. Science in Sport PSP22 at 10-15% solution between your warm up and start of competition. Many people have also found that gels are a great pre race energy boost.
How dehydration can affect performance
When dehydration is a problem, electrolyte loss may also be significant. This can often occur when training indoors or in high heat and humidity. Electrolytes are the minerals lost in sweat, and high losses can negatively affect performance. Electrolyte loss may also be a factor in ultra endurance events, as losses can be significant after 4 hours of exercise. The most important electrolyte lost in sweat is sodium and researchers have shown a wide variation in sodium losses. Sodium losses over a 90 minute period of exercise have been reported to be between 1g and 6g. Since 6g is the suggested total maximum daily salt allowance recommended by the UK food standards agency, and there has been considerable pressure from the government for food producers to reduce the amount of sodium in food energy drinks containing electrolytes should be considered.
