There are a few main things that affect performance on game day: dehydration, nutrition, and stress. Athletes could be in the best physical, mental, and emotional state of their entire season; however, if athletes do not hydrate efficiently, all of the time and effort they have sacrificed will be put in jeopardy.
Athletes MUST drink fluids to stay adequately hydrated. The best way to prevent dehydration is to maintain body fluid levels by consuming plenty of fluids before, during, and after a training/competition. Approximately 60 percent of a body's weight is water. As an athlete trains or competes, fluid is lost through the skin via sweat and the lungs while breathing. If this fluid is not replaced at regular intervals during training and competition, it can lead to dehydration. Proper fluid replenishment is the key to preventing dehydration and reducing the risk of heat-related-illness in athletes engaging in performance-related activities.
More often than not, athletes do not realize the impact proper hydration has on their performance, and thus they usually wait to drink until they are thirsty. By this time, it is already too late. An athlete who waits until thirst to replenish their body fluid is already dehydrated. Most athletes do not become thirsty until more than 2% of their body weight is lost, which can cause a noticeable decrease of physical and mental performance as well as work capacity.
Dehydration affects the body by decreasing the volume of blood in circulation, leading to a decrease in blood to the heart, oxygen to the muscles, and overall athletic performance. Decreased sweat rate, decreased heat dissipation, and increased core temperature also occur when there is less blood circulating. In hot and humid conditions, heat exchange between the body and environment is impaired, which leads to performance reductions and increased risk of heat illness. If athletes do not prepare themselves for this sweat loss, their core temperature usually increases and leads to side effects such as dizziness, disorientation, nausea, diarrhea and gastrointestinal problems.
Athletes who are not sure how much fluid to drink can monitor their hydration using a couple different techniques. One is monitoring the color of their urine. Urine color ranging from a light yellow to dark gold indicates dehydration. Another way to monitor hydration is to weigh athletes before and after practice to calculate fluid loss during activity.
Here are two equations for body fluid requirements-
- NON TRAINING DAYS : 0.5 ounces x body weight in pounds = daily requirements in ounces
-TRAINING / COMPETITION : 1.5 liters for every - 2% of body weight loss (In addition to your daily requirements)
When athletes sweat, their body loses essential electrolytes (mineral salts): sodium, potassium, magnesium and calcium. These electrolytes are important for maintaining normal muscle function (preventing muscle cramps) and for supporting the immune system. Therefore ideal nutrition strategy for training and competing in hot and humid climates should be focused on combining 3 key elements, (water, electrolytes, carbohydrates) not at the exclusion of each other.
Water is a sufficient fluid for hydration in most cases, although there are electrolyte and carbohydrate replacement drinks that are beneficial as well. Adequate intake of these replacement drinks during long or intense training and competition can help to prevent side effects and maintain a safe core temperature, allowing their bodies to work more effectively. Athletes should be consuming at least 16 ounces of fluid two hours prior to exercise, and 5 to 10 ounces during exercise, taken every 15 to 20 minutes. During intense training or long workouts/competitions (longer than 1 hour), a replacement drink containing approximately 6-8 percent carbohydrate is typically most effective in maintaining fluid balance while supplying the muscles with fuel. The replacement drink should also contain a small amount of sodium and electrolytes to assist in retaining water in the body, allowing for increased hydration and quicker absorption into the muscles.
So what is the ideal fluid replacement beverage? It is one that tastes good, provides energy to working muscles during intense training and competition, does not cause stomach/GI discomfort and promotes as well as maintains fluid absorption for the body.
If you have never used a replacement drink before, DO NOT try it for the first time during a competition. Introduce the fluids during your training. Use a trial and error approach until you discover the fluids that work well for you and the timing of fluid replenishment.
Staying educated is your responsibility, providing evidence based information is ours.
6. Jeukendrup, Asker, and Michael Gleeson. “Dehydration and Its Effects on Performance.” Humankinetics. N.p., n.d. Web. Retrieved 12/28/18