The heat has finally set in, and here in muggy Virginia, the humidity is pretty high. I thought it would be pertinent today to lay out some hydration strategies and information to prevent dehydration.
- The body is 60-75% water, depending on who you ask.
- Water acts as a solvent and dissolves and/or transports various proteins, nutrients, and chemicals to the cells. It also carts away the waste products.
- Water is also the medium in which various chemical/enzymatic intracellular reactions...aka, it's how stuff gets done.
- Water lubricates the joints and acts as a shock-absorber for the eyes and spine. I'd say that's a pretty important job, don't you?
- It is the temperature regulator of the body- that is, it comprises most of your sweat.
Clearly, water is essential to proper bodily functions, to say nothing of athletic performance! Therefore, it's imperative that you maintain your fluid balance (fluid balance is simply the relationship between water in and water out).
While we acquire water from our food (it ain't called watermelon for nothing!), most of our fluid intake comes from the beverages we consume. Exercising during summer creates a new best friend for you: your water bottle. Actually, even when you're NOT exercises, the summer means sweating while you're just sitting around so drinking water throughout the day is a wonderful idea.
That said, here is a really, really important factoid to keep in mind: thirst is a poor indicator of hydration status. Typically thirst isn't perceived until 1-2% bodyweight is lost, at this point, performance has already begun to suffer and it will take an effort to gain it back.
What is dehydration?
Dehydration is when you've lost more water than you've taken in. I'd wager that most people are walking around in some level of dehydration, especially during the summer. There are lots of ways to lose water, but since this is a strength coaching writing this, we're going to focus on the sweat-induced dehydration.
Sweat is hypotonic (more water than dissolved particles) so athletes lose both water and electrolytes (because I like to share information, the main electrolytes in the body are: sodium, potassium, chloride, calcium, and magnesium) as they sweat; but they will lose more water that electrolytes because of the proportion of water:electrolytes. However, if athletes are sweating at a high rate, they'll be losing both pretty quickly.
The body has strategies to make up for small electrolyte losses- so if you're only at practice for 1-2 hours inside, you'll probably be ok through the duration of the practice drinking water- just be sure to replace them afterwards.
Just for kicks, here's a chart that shows pee color and the corresponding effects at the various stages of dehydration.
Aside from performance decline, here are a couple other nasty symptoms of dehydration: headache, fatigue, low blood pressure, dizziness, fainting, nausea, rapid heart rate, and constipation.
There is something called hyponatremia where the electrolyte concentration is very low relative to the water concentration. This doesn't happen too often, unless you're drinking gallons of water every day, but it can if athletes have looooong days outside and they don't drink anything that can replace electrolytes. For example, day camps when athletes are outside for several hours is a perfect time to to intersperse sports drinks with water.
So how do we avoid all that and still dominate during the heat?
Before and during practice/sporting event/outdoor event
Start drinking water BEFORE. You should shoot for at least 8-16oz prior to event. (That number will depend on things like bodyweight, climate, activity level, etc. but it's a good starting point.)
During practice/games/tournaments, especially if they're outside, athletes need about 4-8oz of water every 15 minutes.
Drinks with carbohydrates (aka, sugars) are very efficient at delivering electrolytes to body. Most sports drinks include some form of sugar along with electrolytes. However, the concentration of sugars + electrolytes to water is important. 6-8% concentration seems to be ideal, as anything over 10% isn't absorbed will and can cause GI upset. What does that look like?
6% = 30 g sugars/ 8 oz water
8% - 40 g sugars/ 8 oz water
Again, most sports drinks maintain this ratio, but it's always good to check.
Obviously, there are some liquids that are more efficient than others at replacing water: namely water itself. That should be the FIRST thing your reach for, followed by things like sports drinks (that have some sugars and electrolytes in them). Juices, while not a bad option, tend to have too high of a sugar content and can cause GI upset, as can dairy products (at least if consumed before or during exercise). Under NO circumstances should soda be consumed to rehydrates. That's just silly.
So chug that water! Not really, but do drink plenty of water after training. The max absorption rate is around 24oz/hour, so sipping is a much better idea. For the applicable situations, a sports drink can be consumed along with water. You'll know you're done when your pee reaches a pale color again.