I frequently get asked about hydration. Generally, most people assume we need 8 cups of fluid per day. However, the Canadian Society for Exercise Physiology (CSEP), the leader in exercise and personal training research in Canada, recently released new guidelines on this topic.
According to the Institute of Medicine (IOM), we get about 20% of our fluid intake from food and 80% from beverages (all forms, not only water). That being said, we must ensure we are drinking enough beverages to meet the our fluid needs.
Men: 3L (~13 cups) of fluid/day
Women: 2.2L (~10 cups) of fluid/day (with the requirement increased to 2.3L for pregnant women)
During exercise: 250mL (1 cup) of fluid every 15 minutes
note that these guidelines vary as you take into account how much you sweat, type/duration/intensity of exercise, your fitness level, your age, and the environment you’re training in
Where does all this water go?
We lose fluid through sweating, urination, digestive processes, breathing, and through the skin.
Does it have to be water?
According to the IOM, milk, juice, coffee, and tea all count. My personal preference is that water make up the majority of your fluid intake, but if some juice and coffee will help you meet your hydration needs, then go for it (just mind the sugar and cream). Most studies now show that intake of less than 180mg of caffeine (one coffee has ~135mg) per day will not have a strong enough diuretic effect to increase urine output or cause dehydration (American College of Sports Medicine, American Dietetic Association, Dietitians of Canada).
When do I need a sports drink?
If you take part in endurance activities involving bouts of intense effort and lasting more than an hour, a sports drink may help keep you hydrated and fuelled (American College of Sports Medicine, American Dietetic Association). There is a tendency to reach for sports drinks during moderate short-medium length exercise bouts – all you’re doing here is giving your body carbs to burn off, instead of taking from your body’s stock.
Make your own sports drink!
1L water, chilled herbal tea, or coconut water (or any combination of these)
1/4 tsp sea salt (can use less if using coconut water as base)
2 tbsp maple syrup or honey (optional)
(pure coconut water or Emergen-C packs are also great and easy options)