Signs of Dehydration for Runners & How to Avoid It

For runners from the Pacific Northwest, running in the heat can be a foreign sensation! As the days only get hotter year after year, it’s important to be equipped to run safely all summer long.

One of the largest threats to summer runners is dehydration. Not only does dehydration makes running harder, it can also be dangerous. Discover the signs and how to avoid dehydration during your next summer run.

Signs of Dehydration

If you are exhibiting the signs below, you may be experiencing dehydration.

  • Feeling thirsty

  • Fatigue

  • Dry eyes and or/dry mouth

  • Cramps

  • GI distress

  • Headache

  • Confusion

  • Muscle spasms

  • The feeling that exercise is much harder than it usually is

  • Lethargy

What Dehydration Does To Runners

When you’re dehydrated or even just aren’t drinking enough water, your body has to work much harder on everything, especially running.

Your heart has to work harder to pump blood throughout your body. When that happens, it makes it more difficult for your body to regulate its temperature.

That extra work has a significant impact: runners slow their pace by 2 percent for each percent of body weight lost through dehydration.

Dealing with the signs of dehydration alone can derail your run and even the rest of your day. Don’t be caught off-guard by dehydration.

How to Measure Hydration Levels

When you measure your fluid intake and sweat output, you can get a sense of how much more hydration you require.

Start by weighing yourself before your run. After you run, wipe off your sweat and weigh yourself again, adding the weight of any fluid you had running.

If you lost one pound over your run, and drank 8 ounces of water during the run, that adds to 24 ounces of total sweat loss. Divide that by the amount of time spent running to determine your sweat rate. If you lose more than 2-3 percent of your body weight in seat during your run, you need to drink more fluids.

How to Stay Hydrated & Safe Running in Summer

Drink water early and often. Don’t wait to drink all your water until right before you run!

Generally, the National Academy of Sciences recommends:

  • About 15.5 cups (3.7 liters) of fluids a day for men

  • About 11.5 cups (2.7 liters) of fluids a day for women

If you believe you are drinking enough water but still struggling when you run, reconsider your running schedule. Try running earlier in the morning or at night, or switch to running indoors on the treadmill. Remember that no running gains are worth suffering from heat exhaustion!

If you have any questions, please contact us.

Charlotte Spangler