Hydration tips for exercise

You’ve been training for the last 45 minutes. Shirt is drenched. Mouth is dry. Heart is pounding. Every rep you’re trying to muscle out is getting tougher and tougher. Think…if only you had hydrated properly, you would feel half as tired and be able to perform each rep with ease….

Athletes lose sweat at a variety of rates and concentrations depending on environmental conditions, training attire, and the duration/intensity of exercise. Sweat rates can range between 0.5-2.0 L per hour. The ability to recognize your own sweat rate can mean the difference between winning and losing. With excessive sweat losses, athletic performance will be compromised.


Hydrating BEFORE Exercise: Time to top off fluids to ensure you start a training session hydrated. Proper hydration before exercise is key to avoiding muscle cramps and heat-related illnesses

–          At least 4 hours before exercise: slowly drink 5-7 ml/kg of fluids*

–          2 hours before exercise: if your urine is still dark, drink 3-5 ml/kg fluids*

* Consuming a sport drink or salted snacks (e.g. saltine crackers) can help stimulate thirst and retain consumed fluids – higher electrolyte sport drinks will be required if heavy sweating is anticipated.


Hydrating DURING Exercise: Hydration needs varies greatly depending on the individual and their sport/training environment. The goal here is the minimize dehydration and prevent over-hydration. Both will negatively impact sport performance.

* A Sports Dietitian can help to calculate your individualized sweat rate and build an individualized hydration schedule to minimize the impacts of dehydration to performance.

–          Generally, a sport drink of 5-8% of mixed carbohydrates with electrolytes (especially sodium and potassium) from sport drinks and sport gels (with water) are great to maintain hydration. Heavy sweaters will require a higher electrolyte sports formula.

–          Exercise exceeding 1 hour: aim for 30-60 grams of mixed carbohydrates (e.g. glucose, fructose, sucrose and maltodextrin) to help maintain blood sugars and exercise performance. 0.5-1.5L/hour of a standard sport drink can help achieve this.


Hydrating AFTER Exercise

  • This is the time to replace all fluid and electrolyte (e.g. sodium and potassium) losses. For every kilogram of bodyweight lost, replace this with 1.5L of electrolyte-containing fluids. Do this over time instead of doing this in a short period to help enhance fluid retention. Water alone is a poor fluid medium to replace fluid losses as water will simply leave the body as quickly as it entered into it – this means you will see large amounts of urine being produced well before hydration is re-established.
  • If one is to perform or compete again within 12 hours, more aggressive and individualized rehydration strategies will be required.


What you can do to monitor your hydration status:

– Take several days of nude weights first thing in the morning. This can give you an indication of sweat losses and how well you’ve rehydrated during times of heavy training or training at high temperatures.

–  Weigh yourself nude before and after a training session – ENSURE body weight loss never exceeds 2% of your starting weight. When this 2% is exceeded, aerobic, cognitive and mental performance (e.g. skilled and tactical tasks) deteriorates. This is due to: higher glycogen (aka. muscle fuel) use, increased heart rate, increased core temperature and increased central nervous system strain.

– Work with one of our Sports Dietitians to receive a personalized glycogen repletion and hydration schedule. Book and appointment here or call us at 780-450-2027. We do Skype and telephone appointments too!