By Stephanie Dang, Registered Dietitian





Now that summer is here, you’re going to be sweating a little more and needing some extra fluids. Staying hydrated is important for athletic performance, but it’s also crucial for your overall health. But how much fluid do you need for adequate hydration? What is the best way to rehydrate yourself? How do you know if you’re drinking enough? Let me break it down for you.




The first question is: why do we need fluid? Let’s put it this way, lack of fluid can be fatal within as little as a few days, whereas lack of food isn’t fatal for several weeks. In other words, fluid is very important for daily bodily functions! Fluid is involved with regulating body temperature, digestion, facilitating the absorption and transportation of nutrients throughout the body, helping rid waste products from the body, keeping bowel movements regular and soft, and also cushioning organs and joints, to name a few.

Now you may be asking yourself…how much fluid do I need? Does it have to be water? The answer is that water, milk, tea, coffee, sports drinks, smoothies, juice, soup, and even pop counts towards your daily fluid intake. However, juice and pop both contain around 23 grams of sugar (6 teaspoons) per cup, so I don’t generally recommend using either as a primary hydration source due to their high sugar content. That being said, athletes do sometimes need the fast-acting sugars found in juice/pop/sports drinks. In that case, I recommend juice or sports drinks vs. pop. Juice contains some vitamins and minerals, and sports drinks contain electrolytes. Since we lose electrolytes in our sweat, it is important to replenish these. The sugar in the sports drinks also acts as a fuel during exercise. Additionally, the sodium in sports drinks increases our drive to drink, and helps “hold-on” to the fluid more effectively. The general guideline is if your exercise lasts less than a hour, you probably don’t need a sports drink (water will do). If your activity lasts longer than an hour, then a sports drink may be beneficial.

Another great fluid choice is milk, as it contains protein, calcium, and vitamin D. These nutrients are all essential for bone health. Smoothies can also be a good choice since liquid meals are digested faster. Therefore, they may be a better option when you don’t have a lot of time to digest before a game or practice. In addition to these fluid choices, make sure you’re also drinking water! It’s sugar-free, fat-free, sodium-free, and well…free! 

When it comes down to how much fluid you need, this really varies depending on the person. It also depends on the environment (hot or cold), and activity level. Athletes should aim to drink the equivalent amount lost in sweat, which can be calculated by figuring out sweat rate.** The easiest way to assess your hydration level is checking your urine! (see chart below).


Other signs of dehydration include feeling thirsty (or sometimes even hungry), not peeing frequently, feelings of dry mouth, headaches or feeling faint, flushed (red) skin, elevated body temperature, and fatigue or low energy. Losing as little as 2% of your body weight as sweat can have detrimental effects on your performance, so you definitely want to be hydrated at all times. Some tips to stay adequately hydrated throughout the day include:

– Try carrying a water bottle with you everywhere (school, work, gym, in the car)
– Drink water every morning when you wake up
– Drink a glass of fluid with all of your meals and snacks
– Always bring a water bottle (at least 1 litre) when exercising
– Change things up! Try sparkling water instead of plain, or flavour your water with a slice of lemon or lime, adding other fresh fruit (such as grapefruit, watermelon, or cucumber), or herbs (like basil or mint)

Staying hydrated isn’t only important for athletic performance, it’s important for overall health. It’s going to be a hot summer, so go out and buy some more deodorant and a reusable water bottle – you’ll need both!


**Want to know how to calculate your sweat rate or have other sports nutrition questions? Email me at stephmariedang@gmail.com to book a nutrition consultation today!
Many extended healthcare plans will partially or fully cover the services of a Registered Dietitian


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