Summer Hydration

Proper hydration is key for anyone, but especially impactful for athletes. The average person is about 60% water and, as a result, hydration impacts many basic functions. This includes (but not limited to): regulation of body temperature, absorption of water-soluble nutrients (including minerals, Vitamin C, and B Complex vitamins), shock absorption, and keeping your joints moving freely. With improper hydration, people will see elevated heart rate, reduction in blood volume, higher rates of perceived exertion (RPE), less efficiency in using energy stores, and more. This is also just a baseline. Severe dehydration can have serious health impacts. I’ve heard plenty of people cite the fact that sever over-hydration can also have serious health impacts, but the reality is that is not very common. Most people trend towards chronic dehydration rather than over-hydration.

So, what can you do to stay properly hydrated? The National Academy of Medicine (formerly Institute of Medicine) recommends 15.5 cups/day of fluid for adult men and 11.5 cups/day of fluid for adult women. A couple of things to note. This refers to fluid amounts, not just cups of water. That said, water is the most effective fluid for rehydration. And also, it’s important to take environmental factors into account. This is an average baseline. Higher than average temperatures, high humidity, exercise, diet, etc. will all impact the fluid needs for individuals. Not to mention height and weight of any particular person.

A few general tips for staying hydrating in the summer:

-Keep a water bottle handy and drink regularly. Waiting until you are thirsty can lead to being slightly dehydrated. You only need to drink until you are satisfied. You do not need to force yourself to drink excess water.

-If you’re exercising during hotter times of the day, or exercising more than normal, a sports drink with electrolytes is a good idea. Electrolytes (Sodium, Potassium, Calcium, Chloride) help your body retain fluid and also help transmit signals from your brain to your muscles. So, having these in an easy to consume format (sport drink) is a good way to prevent cramp and can help reduce the chance of injury.

-Eat plenty of fruits and vegetables. Many of these foods have a high water content. Strawberries, watermelon, lettuce, cantaloupe, squash, and a few others all have 90-99% water content. Grapes, yogurt, carrots, and pineapple (among others) are in the 80-89% range. So eating healthy also helps keep you hydrated. I could keep going but that seems like a good starting point.

-Pay attention to your body! If you feel thirsty, drink water (or maybe sports drink). Coffee and beer also have high water content but caffeine and alcohol are natural diuretics so also can contribute to fluid loss. If your urine is dark yellow (or darker) make sure you drink water!

-Remember that being outside in the sun also places a higher fluid demand on your body, even if you’re not working out.

-If you lose more than 4% of your body weight during exercise (because of fluid loss), you are at risk for heat exhaustion and heatstroke.

For those who are nerdier about this stuff, here’s a great review of a lot of scientific literature around hydration: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2908954/