In these hot, humid days, maintaining fluid balance should be the #1 priority for all endurance athletes. No other physiological parameter causes as rapid and significant drop in exercise performance as dehydration. As little as a 2% drop in body weight through sweating results in a decrease in exercise performance. That isn’t very much. It’s not uncommon for an individual weighing 150 lbs. to lose 3 lbs. during an endurance bout lasting 45 minutes. Dehydration causes:
- The heart to work harder
- Muscles to fatigue quicker
- Increased levels of the stress hormone cortisol
- Greater depletion of muscle glycogen.
That’s why the number one objective in sports nutrition is maintaining fluid balance and based on sales, water is our number one choice. But there are many reasons why water is not the best sports drink. The key to rehydration is to maintain the fluids you drink. Studies have shown when water is compared to a sports drink, less fluid is retained. The reason being that water can drops plasma sodium levels in the blood which initiates a sequence of events resulting in greater excretion of fluid, which is the last thing you want when you are trying to rehydrate.
Another disadvantage of water is it doesn’t encourage consistent drinking. The salty taste of a sports drink stimulates the thirst mechanism and you continue to drink, which is vitally important during extended exercise in hot and humid conditions. Finally, water doesn’t provide additional energy. Your muscle cells store a finite amount of energy in the form of glycogen. When that is depleted, you bonk or hit the wall. Unlike water, a sports drink provides a continual source of energy in the form of simple sugars that your muscles can draw on and maintain working capacity.
The bottom line is you must rehydrate during extended exercise on hot and humid days and water can help you maintain body temperature and depletion. However given a choice, a sports drink particularly an electrolyte-carbohydrate-protein sports drink such as Accelerade, offers so many additional advantages, it should be your #1 choice.