Importance of hydration in endurance sports
Words: Dominique Harmse ǀ Photos: Enervit Sports. Article from the DO IT NOW Magazine..
Summer means that the annual season for endurance events has begun and it also brings high temperatures.
In our warm South African climate, it is essential for endurance athletes to know about the correct fluid-electrolyte supplementation before, during and after training or racing, so they don’t damage or impede their performance by not hydrating properly.
The body is composed of 60% water and the water content of muscle can be as high as 80% in an athlete. It is then easy to understand that hydration plays an important role in exercise performance. During an intense workout that lasts 30 minutes or more, one of the most important ways to help your body perform at its peak is to provide it with the correct fluid-electrolyte supplementation. However, this is often neglected.
It has been shown that even a moderate fluid loss of just 2% of body weight (1½ kg in a person weighing 75 kg) can significantly reduce performance levels.
When the body loses more water than is consumed, this dehydration increases physiological strain with an increase in body temperature, impaired exercise performance and can contribute to serious heat illness. Added to this, dehydration increases the athlete’s perceived exertion. In other words, in a given exercise session, the dehydrated athlete will perceive the exercise to be more challenging than if the same session was undertaken well hydrated.
“Athletes are recommended to not only rely on thirst as an indicator of dehydration. A good tip for athletes is to monitor changes in body weight during training sessions as a way to estimate their individual sweat rate. This can be done by measuring weight before and after training, taking into consideration any fluid consumed during exercise. A sports dietitian can assist in customising the athlete’s fluid plan,” says Monique dos Santos, a registered dietitian and nutrition consultant.
It is common practice to supplement electrolytes (sodium, chloride and potassium) during endurance exercise to prevent muscle cramps. Interestingly, muscle cramps and fatigue may also be associated with dehydration and depletion of energy stores (glycogen). Sports drinks containing electrolytes, fluid and carbohydrates are ideal supplements for endurance athletes, as they can help sustain fluid-electrolyte balance and exercise performance.
Carbohydrate-based sports drinks can be used to meet fuel (carbohydrate) needs, while attempting to replace water and electrolyte losses. As the muscle uses different carbohydrates at different rates, a sports drink that contains a mix of sugars, such as glucose, sucrose, fructose and maltodextrin, will deliver the highest rates of carbohydrate to exercising muscle. Glucose, sucrose and maltodextrin are quickly used, whereas fructose and galactose are slowly used. The advantage of this is that more energy can be delivered to exercising muscle, therefore potentially improving performance.
What should you drink before you exercise?
Athletes should consume a drink about 20 to 40 minutes before the start time, so that potential digestive problems can be avoided. Choosing a low-GI drink is important. If a drink is too high in carbs it can lead to a rise in blood sugar, which has the potential to inhibit the use of fatty acids during exercise and can cause reactive hypoglycaemia. This occurs when high-GI carbs are rapidly absorbed by the body, as can be the case with some drinks that contain large quantities of glucose, sucrose or maltodextrins. For example, a 300 ml sports drink that contains 6% carbohydrates with a high GI can lead to significant insulin stimulation, which has the potential to negatively affect the body’s ability to oxidise fats during exercise.
Oxidisation of fats occurs when an athlete’s body burns fat (instead of carbs) and uses it as a source of energy. Weight loss and increased lean muscle mass are associated with fat oxidation, all of which are advantageous to athletes. Therefore, athletes who train regularly will have an improved ability to oxidise fat when carbohydrate stores are low.
What should you drink during exercise?
A drink consumed immediately before or during exercise should replenish what is going to be lost in sweat, in the shortest time possible. It must pass quickly through the stomach, be absorbed rapidly in the intestine and should supply a limited level of carbohydrates to the body. The time a drink spends in the stomach depends on its concentration of carbohydrates. A quick passage through the stomach is possible when it contains 5% or less of carbohydrates and has the right levels of minerals.
Depending on the intensity of the exercise, isotonic drinks (contains similar concentrations of salt and sugar as cells in the human body) are best for fast absorption of water. For less intense physical activity, hypotonic drinks (contains a lower concentration of solutes outside the cell than inside the cell) should be consumed. Plain water is absorbed more slowly compared to some saline-energy drinks, even though a person who has sweated intensely should rather drink water versus not drinking at all. Drinks should also be cool, especially if the temperature and humidity are high, as those drinks with a temperature below 15°C spend less time in the stomach compared to those that are warmer. However, make sure the drink is not too cold, as this can cause gastric or abdominal cramps.
What should you drink after you exercise?
After exercise, you should ideally consume a drink that replenishes the water and minerals lost through sweating. It should provide a higher level of carbohydrates than pre and during drinks, branch chain amino acids and vitamins to help the body recover quickly. The body needs fast absorbing carbohydrates, such as maltodextrin and dextrose, to help re-synthesise the glycogen consumed by muscles. This is especially important when you are exercising regularly, to keep your body in tip-top shape.
Branch chain amino acids help to repair muscles and promote the recovery of protein stores and vitamins C, E and B6, which all help with fatigue, metabolism support and quick recovery. Make sure you consume a drink within 30 minutes of physical exercise – this is the first step towards optimal performance in your next challenge.
Dehydration affects performance, particularly during the hottest times of the year and during high-load periods, when you train for many hours every day. To keep your body optimally hydrated and performing at its best, ensure that you are hydrating properly with the right fluid-electrolyte supplementation before, during and after exercise, as well as avoiding any unnecessary sun exposure. Enervit Sports has a sport and recovery drinks, as well as a complete line-up of endurance sports nutritional supplements that provide specific products for every step of an athlete’s performance strategy: before – to increase the availability of energy; during – to combat fatigue; and after – for a quick and optimal recovery.
About Enervit’s sport and recovery drinks
The Enervit G Sport drink is an energy-providing saline solution supplement that contains real dehydrated juice, available in orange and lemon flavours. It can be prepared as an isotonic or hypotonic saline supplement solution. It contains an ideal mix of maltodextrins and glucose, which are assimilated at different rates in the body for prolonged performance. It provides the body with essential mineral salts, including sodium, chlorine and aspartates, potassium and magnesium as well as essential vitamins needed for the body to produce energy. For more information visit http://www.enervitsport.com/za/products/enervit-g-sport-drink-orange-420…
The Enervit R1 and R2 Sport Recovery drinks are energy supplement drink solutions for rapid recovery after intense training or competitions. Both drink solutions rebalance the body’s water and mineral content when they have been depleted by heavy sweating and contain fast absorbing carbohydrates, branch amino acids, L-glutamine, vitamins and minerals. Branch chain amino acids (leucine, isoleucine and valine) help to repair muscles and promote the recovery of protein. Glutamine helps to combat fatigue and counteracts the effects of burnout. Vitamins C and E assist muscle recovery after training, help with and fatigue, help to protect cells against oxidative stress and contribute to normal energy metabolism and vitamin B6 helps with the normal metabolism of glycogen and proteins. R1 Sport Recovery is suitable for recovery after less intense or shorter workouts, whilst R2 has a higher concentration of ingredients for recovery after more intense or longer workouts. For more information visit http://www.enervitsport.com/za/products/pag-1084#3:1084
The Enervit product range is available at Dischem stores nationwide, at selected independent sporting retailers or online at www.enervitsport.com/za.
For more information about Enervit’s range of products, visit www.enervitsport.com/za or follow them on Facebook: www.facebook.com/enervitsa and Twitter: www.twitter.com/EnervitSA