Hydration While Running

Lait au chocolat

Published on 5 July 2017
by Ariane Lavigne
When you go for a run, you always wonder if it is necessary to wear a hydration belt or to bring a bottle. Although it is true that our level of hydration can influence your performance, depending on the length and intensity of your run.


The first step is to get hydrated before you run.

Pay attention to your thirst signals and drink anywhere from 5 to 10 ml per kilogram of body weight per hour (300 to 600 ml per hour for a person weighing 60 kg). A great clue whereas you had enough water or not: your urine should be almost clear, similar to lemonade [1]!

If you drank sufficiently before leaving, drinking while running will be of less importance if your run lasts one hour or less. However, if the weather is hot and humid, or if your run lasts for more than one hour, you will need some fluids, around 7 to 10 ml per kilogram of body weight per hour.


For Runs That Last Less Than an Hour

Generally, it is less critical that you drink if you are leaving for less than one hour. Scientific studies proved that rinsing your mouth every ten minutes for ten seconds with 20 to 25 ml of a sports drink containing carbohydrates allowed increasing performances without causing any gastrointestinal issues [2]. However, if you are training to participate to a half or a full marathon, it is important you get used to wearing a hydration belt, even if you run for a short period of time.


For Longer Runs (1.5 Hours or More)

The general practice is to drink 7 to 10 ml liquids per hour, intakes of 30 to 60 g of carbohydrates, and 500 mg of sodium per hour to maximize performances. You will need to adjust those quantities according to the efforts, intensity, outside temperature and your personal tolerance. It was also suggested for a long time, to avoid weight loss through dehydration of more than 2% of body weight during a run. However, the subject is still controversial as it was proven, in a recent study, that marathoners with the best results had lost over 3% of their body weight, and that the slowest runners were less dehydrated [3]. Therefore, it would be crucial to trust your thirst signals, and drink as soon as you feel a dry mouth or thick saliva. This last criterion is less precise, however, I suggest that you take note of what you drink when training in order to establish the right quantity, type of drink, bottle, or hydration belt that best suits your needs and which allows you to run faster!


Carbohydrate content: Sports drinks, gels, gumdrops and fruits

Gel (example: Gu) 1 gel = 20 g
Sports drink (example: Gatorade) 500 ml = 26 g
Gumdrops (example: Honey Stigner) 1 packet = 39 g
Fruit compote (example: GogoSqueez) 1 pouch = 15 g
Banana 1 medium = 30 g

[1] Armstrong LE, Soto JA, Hacker FT Jr, et al. Urinary indices during dehydration, exercise, and rehydration. Int J Sport Nutr. 1998; 8:345–355.
[2] Rollo I, Williams C. Effect of mouth-rinsing carbohydrate solutions on endurance performance.
Sports Med. 2011. 1; 41 (6):449-61.Review.
[3] Goulet ED. Dehydration and endurance performance in competitive athletes. Nutr Rev. 2012; 70 Suppl 2:S132-6. Review.


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Ariane Lavigne
Nutritionist at VIVAI and a member of the National Snowboard Team