Role of Hydration in Successful Workouts

The main reasons dehydration has an adverse effect on exercise performance can be summarized as follows:

• Reduction in blood volume
• Decreased skin blood flow
• Decreased sweat rate
• Decreased heat dissipation
• Increased core temperature
• Increased rate of muscle glycogen use

Before Activity
The goal is to be hydrated well before you even begin your physical activity. Don’t wait to hydrate until your body is telling you that you are thirsty. Anticipate your thirst and take a sip of water to stay ahead. Plan your activities a day in advance and properly hydrate the evening prior to put yourself in the best possible position to succeed.

During Activity
To keep up with your hydration throughout your activity, make sure to be drinking enough fluid to combat the water lost through sweat while also avoiding excessive body fluid loss and over-consumption of fluids.3 The American Academy of Pediatrics recommends young athletes to drink 1 – 1.5 liters or 34 – 50 ounces of water per hour during the activity. 50 ounces of water is equal to a little more than 3 disposable water bottles. Activities lasting longer than 90 minutes require electrolyte replenishment. Having a sports drink along with your water is helpful and will provide additional benefits in staying hydrated.

Post Activity
The goal of hydration post activity is to replace any fluid deficit you lost during your activity. Replacing these fluids after your workout or game will restore hydration, improve recovery, reduce hypo-hydration symptoms, and decrease post-exercise fatigue. 3 In terms of how much you should hydrate post activity, keep a close eye on your body weight to help monitor how much sweat you lost. If you lost plus or minus 1.5% body weight, you are good to go and properly hydrated. If the number is greater than 1.5%, then you are leaning towards dehydration and should start hydrating as soon as possible.