A friend of mine, who is also a very good soccer player and coach, strongly suggested that I remind folks of the critical importance of fluid intake, especially for youth players. Here are the US Soccer Federation guidelines regarding fluid intake:
For ease of reading I am quoting here key passages from the first document:
Heat-induced illness is one of the most preventable sports injuries. Parents, young athletes
and coaches need to understand the factors that put children and adolescents at risk for heat related illness and take steps to prevent it. Children face unique stresses when they exercise in the heat. Here are physiological/psychological reasons placing children at risk:
1. Children absorb more heat from a hot environment because they have a greater surface area to body-mass ratio than adults. The smaller the child, the faster they absorb heat. They also have a reduced ability to lose heat through sweating.
2. During prolonged exercise, children and adolescents frequently do not have the physiological drive to drink enough fluids to replenish sweat losses.
3. Some youth athletes may be under intense pressure to make a competitive squad and may not want to report feelings of heat distress or take the appropriate amount of time to rehydrate.
According to the American Academy of Pediatrics:
• Before prolonged physical activity, the child should be well hydrated. The child should drink 12-16 ounces of fluid approximately 30 minutes before getting to the field.
• During the activity, periodic drinking should be enforced even if the child does not feel
thirsty. Each 15-20 minutes the child or adolescent should consume:
− 5 ounces of fluid for a player weighing 90 lbs or less
− 9 ounces of fluid for a player weighing more than 90 lbs
• Once the activity is over, players should drink water or a sports drink every 15-20
minutes for the first hour after activity. The rate of fluid ingestion is generally 1.5 pints
of fluids for each pound of weight lost.
• Adolescent males typically lose 1-1.5 liters per hour when performing intense soccer practices/games in the heat, while younger males and females will lose from 0.6 to 1 liter per hour.