Cold + Dehydration

Cold + Dehydration

Combatting the cold weather with… more water?

by Richard Fineman and Greg Grosicki

The beginning of a New Year often provokes the realization that race season is right around the corner. After taking some deserved time off, fitness enthusiasts everywhere have begun to make a push to get back in shape. As if early morning alarms weren’t bad enough, the east coast has been struck with a particularly cold winter this year (proof that Global warming is an alternative fact). Unfortunately there are only so many sessions on the indoor hamster wheel (treadmill) one can take before deciding to brave the frozen tundra in hopes of preserving some semblance of sanity. So you spend 10 minutes gathering your winter gear and putting it on, layer after layer. After what feels like an eternity you finally get your shoes on after taking that selfie to brag about what a bad ass you are for running in negative degree temperatures you head out the door. Freezing your ass off you wait for your Garmin to find satellites and like clockwork that’s when it hits REALLY need to pee. Sound familiar? While we can’t tell you how to stop this, because if you did it would be really bad if you did, like kill you bad, we can tell you that if this series of events hits close to home you aren’t alone.


If there is one thing we’ve learned in ten years of studying human physiology its that the human body is amazing capable of protecting itself. Interestingly, that urgent need to pee when you step outside in the cold is just one of many intricate mechanisms through which our body protects itself. Sensing the cold environment, all of the blood in our distal extremities (arms and legs) is forced to our core to prevent a drop in temperature. For a real-life example, think about the rate at which water in a puddle freezes in winter vs. the Atlantic Ocean; your core is now the Atlantic Ocean. As a result, the amount of blood in the internal organs is now greater, just as if you were to consume a big glass of water. Sensing this increase in blood volume, the heart releases a special hormone called atrial natriuretic peptide or ANP. ANP is the hearts way of communicating to the kidneys that they need to get rid of some water. So sensing this increase in ANP levels the kidneys filter “excess” fluid into the bladder leaving you debating a return to the toilet while you wait for your Garmin to find satellites.


In summary, the cold triggers a series of events that leave your body thinking it has too much fluid and telling it to pee. People also often tend to drink more alcohol and coffee (or maybe this is just graduate students) and less water during the cold winter months. It is important to stay hydrated, especially in the cold! Not enough water can lead to headaches, dizziness, and trouble sleeping, so here are a few tips to help you stay hydrated during winter:


  • Drinking warm water can help! Not only does it hydrate, but helps keep you warm and toasty.
  • Try to avoid drinking teas, coffee and other caffeinated products because caffeine acts as a diuretic and makes you pee even more
  • Encourage yourself to drink by finding a fluid replacement that appeals to your taste, personally we love DRINK Simple, an all-natural product loaded with electrolytes to help replace key minerals!


Richard Fineman attended Columbia undergrad where he swam for the varsity swim team. He is currently in the final year of his PhD at MIT where he studies human biomechanics and wearable devices (Garmin 2.0). He is also an amateur triathlete racing for Team Wattie Ink and yoga instructor.


Greg Grosicki has a PhD in Human Bioenergetics and is current working as a Post-doctoral fellow in Tufts Medical Center. Greg is an amateur triathlete racing for Team Every Man Jack and he is looking forward to racing Ironman Kona in 2018 where he doesn’t expect cold weather to be much of a problem.

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