input: [Recommendation] Hydrate, hydrate, hydrate [Why] 
output: Loss of water and electrolytes due to sweating during exercise can result in decreased performance and other problems, so remember to drink plenty of water and electrolyte-balancing sports drinks prior to, during, and after exercise. Water is the most abundant substance in the human body and is essential for normal physiological function. Water loss due to sweating during exercise can result in decreased performance and other problems. The American College of Sports Medicine's recommenations for fluid consumption by exercisers were updated in 2007.36 Fluids should be consumed prior to, during, and after exercise, especially when extreme conditions of climate, exercise intensity, and exercise duration exist. Enough fluids should be consumed up to two hours before exercise begins to produce urine that is not too dark or concentrated. The amount of fluid that should be consumed during exercise will vary depending on many factors, including personal sweating rate, climate, and type and duration of exercise. Exercisers should generally drink to satisfy their thirst, and should also monitor changes in their body weight during exercise. If weight loss approaches 2% of body weight, then fluid consumption has been inadequate to prevent dehydration. After exercise, enough additional fluid should be consumed to equal 150% of weight lost (24 ounces of fluid for each pound of weight loss). Some individuals may experience an increase in body weight during exercise; this can indicate that too much fluid has been consumed, which can lead to a potentially dangerous condition called hyponatremia (low blood sodium levels) even if electrolyte-containing sports drinks are used. A professional knowledgeable in sports medicine can help formulate an individualized plan for fluid consumption during exercise. Flavored sports drinks containing electrolytes are not necessary for fluid replacement during or after brief periods of exercise, but they may be more effective in encouraging the athlete to drink frequently and in larger amounts when needed.37 Consuming fluids along with meals or salty snacks before and after exercise will also encourage sufficient fluid intake and may improve fluid retention in the body.38