PEN® eNews 15(8) August 2025 - Hydration

Do You Need an Electrolyte Beverage? 

Are electrolyte beverages (e.g. sports drinks with or without caffeine, coconut water) safe and effective for improving athletic performance in athletes?

Sports Drinks Without Caffeine
For healthy young adults performing endurance activities (e.g. cycling, running), hypotonic sports drinks (<275 mOsmol/kg) consumed throughout exercise may hydrate better than iso- and hypertonic sports drinks or water.

Water is the best beverage for children and youth engaging in routine physical activity and play-based activities, although sports drinks may be appropriate for children and youth participating in physical activity lasting longer than one hour and/or when activities take place under hot, humid conditions.

Energy Drinks and Sports Drinks with Caffeine
Sports or energy drinks containing 3 mg/kg body weight of caffeine probably improve athletic performance in healthy, active adolescents and adults compared to taste-matched, non-caffeinated drinks. Adverse effects are not known.

Remarks

Hypotonic sports drinks contain carbohydrates and electrolytes in lower concentrations than human body fluids (i.e. <275 mOsmol/kg). They help maintain hydration during exercise by increasing blood volume and reducing diuresis. Caffeine may improve athletic performance because it reduces the level of pain and exertion the athlete experiences.

To see the full practice question, including Recommendations for adults at risk of hypertension, Evidence Statements, Remarks and References, click here. 

Hydration for Sports Nutrition

We know that hydration is important, especially for athletes. But how much fluid should you drink, and what types of fluid are best? Here are some practical tips from the PEN System’s Sports Nutrition - Hydration for Adults handout.

• Before exercise: Aim for 5 to 10 mL (1 to 2 tsp) per kilogram (kg) of body weight.

• During exercise: Sip fluid during your activity. Avoid gulping or drinking too quickly as this can lead to over-hydration.

• After exercise: Drink 1.25 to 1.5 L (4 to 6 cups) of fluid per kg of body weight you lost.

How do you know if you’re dehydrated? One tip: check the colour of your urine. Light yellow and clear urine is a sign you are well hydrated. Dark yellow (apple juice colour), strong smelling urine could mean that you are dehydrated.

Drinking Fluid to Staying Hydrated

Even if you aren't an athlete, it can be difficult to stay hydrated in the summer. How much fluid you need every day depends on your age, sex and activity level. Here are some practical tips from the PEN System’s Guidelines for Drinking Fluids to Stay Hydrated (Adults) handout.

• Adult males need approximately 3 L (12 cups) fluid each day.

• Adult females need approximately 2.2 L (9 cups) fluid each day.

• Fluid needs increase during pregnancy and lactation.

Fluids include water and other beverages such as milk, juice, broth or soups, coffee and tea. Water is one of the best fluid choices, but it is a myth that you need 8 cups a day to stay healthy.

Seeking Canadian PEN Client Handout Reviewers

Do you specialize in pediatric dyslipidemia, multiple sclerosis, gallstones or peptic ulcer disease? If so, we need you to review related PEN System client handouts!

We are looking for Canadian dietetic specialists to volunteer to review some of our PEN handouts for clients. We are looking for reviewers for these specific handouts below:

• Eating Guidelines for Multiple Sclerosis

• Eating Guidelines for Peptic Ulcer Disease

• Eating Guidelines for Gallbladder Disease

• Heart Health (Children with High Blood Fats)

Key aspects of the review include:

• Using your professional knowledge/ clinical expertise to provide feedback on the information/ content provided in the handout.

• Based on interactions with your clients and questions they may have about the related diet in your practice, what information is missing in the handout that we should consider adding.

• General feedback - flow of information, clarity, what doesn't work well.

If you are interested please email jane.bellman@dietitians.ca with the handouts you would be interested in reviewing and your timelines for availability.

Thank you to our valued contributors!