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Eight glasses of water a day, right? Not so much when you’re a runner.
Runners need to hydrate before, during and after our runs, but most of the time, we’re not going to take a water bottle or hydration pack for a short 30- to 60-minute jaunt.
There is no single rule for how much water to consume during a run because everyone’s body is different.
That being said, when temperatures and humidity spike, you definitely need to drink more to make up for how much more you’re sweating. And even if it’s cold out, that doesn’t mean you don’t need any water–you’re still sweating and need to replace what you lose.
Here’s what you need to know to stay hydrated.
Hydrate before you hit the road.
Consume at least 6-8 ounces of water before you go out for a run. This will keep you hydrated for a short workout, and if you’re going out a little longer you won’t be too thirsty when you get back. If you have a bit of time before you need to hit the pavement, you can drink more water a couple hours out – to give it time to get through your system — then 6-8 ounces shortly before you head out the door if you need a bit more.
Drink when thirsty.
Most experts no longer recommend a specific water amount per length of time you’ve been working out. Instead, they recommend drinking any time you’re thirsty. If you have a hydration pack, it’s easy to just take small sips here or there. But if you’re counting on water fountains, you made need to get a little bit more into you if they’re spaced far apart or it is super hot and humid out.
Pay attention to post-workout hydration.
Just because you’re done with your run and drank water during your workout doesn’t mean you don’t need more. Check in with yourself when you get home – you’ll likely find you need a couple glasses, particularly if you weren’t drinking on the run.
Check your urine color.
You want your urine to be a light yellow color – not dark yellow (a sign of dehydration) or completely clear (a sign of overhydration).
Consider sports drinks.
Water is very important, but you can also supplement your workout with a sports drink that will help replace some of the electrolytes you’ve lost during your sweat session. This is particularly key for longer runs (more than an hour) and races, especially if you’re not eating a snack or gel on the go.
Watch for signs of dehydration.
Symptoms of dehydration include dry mouth, thirst and headache. You may also find your performance starts suffering as you become dehydrated. Severe dehydration can cause vomiting and dizziness. In extreme heat, also watch out for heat stroke and heat exhaustion.
Check your weight before and after runs.
If you want to know how much you’re sweating, weigh yourself right before you go for a run, then immediately when you get back (before going to the bathroom). If you’ve been hydrating along the way, you shouldn’t see much of a change, but if you’re dehydrated, the scale will likely read lower – an indication you need to drink more.
There is such as thing as too much water.
Drinking too much water during exercise is dangerous – and even deadly. Hyponatremia is a condition that happens when the sodium level in your blood dips too low. Cells try to absorb the excess water, leading to swelling, which can threaten the brain. Symptoms include nausea, vomiting, headache, confusion, loss of energy, seizure and coma. The condition does not always lead to death, however, runners have died during or after major races such as the Boston Marathon and Marine Corps Marathon.
For more from Katharine Lackey visit Kat Runs D.C.