Hydration and the Young Athlete
September 23, 2019 03:00PM
Fall sports are in full swing and youth athletes of all ages are busy with both school and activities. With tight schedules and cooling weather, kids in youth sports often overlook the importance of proper hydration. When the body loses excess fluids during activity, both health and performance will suffer. Losing as little as 2% of body weight can lead to impaired performance. For a 75 pound 10 year-old, that is just 1.5 lbs. lost during a couple of hours of sports or physical activity.
It is important to practice good daily hydration habits. While there is no “magic number” when it comes to daily fluid intake, it is important to drink often and enough during the day so that urine is clear to light yellow as the day progresses. Kids and teens should be using the bathroom at school at least once daily. I’m often surprised to learn that the kids and teens I work with go 7-9 hours without using the restroom! That is a sure sign that they are not taking in enough fluids.
Fluids come from milk, water, beverages and food. Foods such as fruits, vegetables, soups, smoothies and yogurt contain a high percentage of water.
In terms of daily fluid needs, a simple rule of thumb is to take body weight in pounds and divide by 2 to get a starting point for total fluid needs. For instance, a 60 pound child will require roughly 30 oz. daily for basic body processes. Physical activity, heat, humidity, fevers and gastrointestinal illness are common factors that increase this requirement.
When your child or teen is not well hydrated, they may experience low and/or dark urine output, thirst, headaches, muscle cramps, and irritability. Thirst is a late indicator that body water stores need replenished so sipping water throughout the day is optimal.
Before, During and After
Guzzling water or other beverages right before activity is not advised. A sloshy stomach will feel uncomfortable and the fluid does not have time for absorption. Full hydration means that cells, muscles, and organs have enough water to fulfill important body functions during exercise.
While fluid needs will vary with the individual, it is generally advised to drink at least 2 cups of water (16 oz.) 2-3 hours before training. Shortly before practice or a game, young athletes are advised to drink another 8 oz. of water.
During Sports and Activities
Kids and teens should always have access to fluids during practice, games and events. They will ideally drink around 4-8 oz. of water every 15-20 minutes. While water should be the fluid of choice, there are times when a standard sports drink is needed to optimize hydration and assure that body sodium does not fall to a dangerous level. Adding a sports beverage is generally advised if an activity is in extreme heat, a child or teen sweats excessively, or the activity is continuous for more than one hour.
These are general guidelines that should always be individualized for the athlete. When exercising in hot, humid or extreme conditions such as high altitude, a teen may require a quart or two of water per hour. In these conditions, it is also important to replace sodium so include a sports drink every hour. In addition to fluid and sodium, sports drinks often contain potassium, chloride (both electrolytes), and sugar to supply energy.
Recovery and Rehydration
For every pound of fluid lost, it takes 1.25 to 1.5 times the fluid to fully replace losses. Weighing your child before and after practice will give an indication of the amount of fluid loss. For instance, if your child loses 1 lb. during practice, they will need 20 - 24 oz. of fluid to fully rehydrate.
If Your Child is Sick
Dehydration can be dangerous in kids or teens who are recovering from an illness. According to guidelines from the American Academy of Pediatrics, “Any child or adolescent should avoid or limit exercise, sport participation, or other physical activity in the heat if he or she is currently ill or is recovering from an illness, especially those involving gastrointestinal distress (e.g., vomiting, diarrhea) and/or fever.“
Where to Find Expert Advice
If you have questions or concerns about proper hydration or sports nutrition for your child, be sure to talk to your pediatrician and dietitian. A registered dietitian with expertise in working with young athletes can conduct a thorough assessment and make individualized recommendations about optimal foods and fluids.
Registered Dietitian Connie Liakos, MS, RDN, CSSD, LD, is board certified as a sports science dietitian. She is available to counsel child and teen athletes from the Portland metro area. Connie has worked with all types of athletes from recreational to elite competitors.
USOC Sport Nutrition Team, Hydration Factsheet 2015, https://www.teamusa.org/nutrition
Council on Sports Medicine and Fitness and Council on School Health, Pediatrics Sep 2011, 128 (3) e741-e747; Climatic Heat Stress and Exercising Children and Adolescents, https://pediatrics.aappublications.org/content/128/3/e741