Water is essential to our body. It helps to digest foods, makes up a large portion of our blood volume, helps maintain our blood pressure, is a large component of our muscles (~80% of your muscles are water!), and helps to regulate our body temperature. Not only can dehydration impact your mood, but it can also impact your work in the heat.

Working in the heat is already hard enough mentally and physically. But if you’re dehydrated on top of that, you will experience even greater physiological strain, and you might notice that your mood and cognition are worse too. This combination of being dehydrated AND working in the heat will increase the odds of accidents at work, decrease your performance, and increase your risk for heat-releated injuries and illnesses. But don’t worry, there is an easy fix for this…. drinking water!

So how do you stay hydrated throughout the work day?

  • Start by drinking a glass of water when you wake up in the morning. Starting your day hydrated will help to keep your core temperature lower by allowing for your body to sweat adequately (and get rid of heat) throughout the work day.
  • If possible, carry a water bottle with you throughout the day to make drinking water easy and accessible. If it’s not cold water, don’t worry about it. Although it may not be pleasant to drink, warm water won’t necessarily make you hotter.
  • Don’t limit your water intake and always drink when you’re thirsty.
  • NIOSH & OSHA recommend drinking ~8 oz water (1 cup) every 15-20 minutes. But may not be the correct amount for you. For a more accurate hydration plan, you’ll need to calculate your normal sweat rate. Kenzen can help you & your team with this. But for right now, you can weigh yourself before vs. after your workday to figure out exactly how much water you lost (through sweating).

Rule of thumb: you need to drink 20 oz. (about 1.5 water bottles) of water per pound of body weight lost through sweating.

  • Limit alcohol intake. Alcohol dehydrates you and impacts your body’s ability to properly regulate body temperature.

  • Good news: if you regularly consume caffeine, it will not impact your hydration or your ability to work in the heat. So don’t worry about having your 2-3 cups of coffee or tea each day.

How can you check to make sure you’re staying hydrated?

Your urine color (in the toilet bowl) should be a lemonade color (or lighter). This is the easiest way to check that you’re hydrated.

If you’re using a porta-potty where it’s hard to see your urine color in the toilet bowl, you can count how many times each day that you have to use the restroom.

If you’re urinating at least 7 times per day, you’re hydrated. Any less than 5 times per day and you’re likely dehydrated. This would mean that you’re urinating at least once every 2 hours or so.

Glass of water

Three tricks to increase your water absorption:

  1. Lightly salting your foods (especially during the first two weeks you’re working in the heat) can help your body to absorb more water.
  2. Drinking fluids with electrolytes (especially sodium) will help to absorb the water you drink. Just watch those sugars in the drinks- you don’t need them!
  3. Your body can only absorb water at a certain speed… what that means is that you need to pace yourself in drinking the water back after working hard in the heat. You can’t just “chug” a bunch of water at the end of the work day— you will just urinate it out.

Rule of thumb: your body can absorb ~8 oz. (half of a water bottle) every 15 minutes, so try to pace your water drinking to that rate.



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  • Tucker, M. A., et al. “Reliability of 24-h void frequency as an index of hydration status when euhydrated and hypohydrated.” European journal of clinical nutrition (2016).
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  • Armstrong, Lawrence E., et al. “Mild dehydration affects mood in healthy young women.” The Journal of nutrition 142.2 (2012): 382-388.
  • Shirreffs, Susan Margaret, et al. “Post-exercise rehydration in man: effects of volume consumed and drink sodium content.” Medicine and Science in Sports and Exercise 28.10 (1996): 1260-1271.
  • Bain AR, Lesperance NC, Jay O. Body heat storage during physical activity is lower with hot fluid ingestion under conditions that permit full evaporation. Acta Physiol (Oxf). 2012;206(2): 98–108.
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