Why Do I Get Dehydrated During Cold Winter Weather?
Temperatures may be dropping but your need for hydration isn't
It’s that time of year again, the days are growing shorter, and the temperatures are cooling down. For me, that means throwing on a cozy sweater and taking my dog on a long stroll through the park as the autumn leaves begin to change color. But with the change in temperature, I tend to feel less parched and forget to bring my water bottle.
Is Hydration Really THAT Important During the Winter?
While you may not be sweating as intensely when the cold weather rolls in, remaining hydrated is just as important. Drinking an adequate amount of fluid before, during and after a workout is crucial to achieving optimal performance. Even on a rest day, it is just as important to stay hydrated so your body can perform all of its functions properly.
Simple rule of staying hydrated: The amount of water that you lose through breathing, sweating, and using the restroom should be equal to the amount that you take in.
Let's talk about dehydration. Have you ever been so thirsty that when you finally drank some water, it was the best thing you have ever tasted? This probably means you were in a state of dehydration and your body did not have enough water to properly function. Some signs that you may be dehydrated include headache, tiredness, cramping, dizziness, and dark colored urine.
Water is not the only thirst quencher needed to maintain hydration, electrolytes are also a key element. Electrolytes are minerals with an electrical charge that are consumed from food and beverages. After consumption, they can be found in your blood, urine, tissues and other fluids. They are important for hydration because they aid in balancing the amount of water that is in your body.
What causes dehydration in cold weather?
While your sweat rate might not be as high as it is in the middle of a humid July day, there are still many factors that may cause you to become dehydrated during the colder months. Some are related to loss of fluid and others are related to your intake. Let’s take a deeper look into what the causes are.
Cold-induced diuresis is a phenomenon discovered by scientists, simply put, it means an increase in urine output due to cold temperatures. When you are outside on a cold winter day, your blood vessels begin to narrow in order to increase blood flow around your vital organs leading to a rise in blood pressure.
Now you may be wondering, what does this have to do with increased urination? If you didn't already know, your kidneys play a large role in blood pressure regulation, in addition to filtering waste out of your blood which creates urine.
When you are cold, and your blood pressure increases, your kidneys work harder to keep your blood pressure in check. More blood is being filtered, therefore more urine is being produced causing you to need to use the restroom more, thereby releasing more fluid.
Respiratory water losses
Believe it or not, we lose more water through respiratory losses on colder days than on hot days. Picture yourself outside on a cold day where you can see your breath. What you are actually seeing is water vapor leaving your body. Studies have shown that you lose more water while exhaling in colder temperatures than in warmer temperatures.
As the temperatures outside drop, the air around us tends to be drier. When dry air enters a humid environment like your respiratory tract, it can cause further fluid losses. In some cases, this can even lead to respiratory problems such as asthma, bronchitis, sinusitis and nosebleeds.
If you have done an outdoor workout in bitter cold temperatures, you are aware that you will start out shivering. However, within minutes of physical activity your body begins to warm up. In response to the warmth, you will begin sweating so your body can cool off.
The type of clothing you wear in the winter can impact how much water is lost via sweat. For example, if you are wearing a big puffy winter coat while exercising, your body will become hotter quicker, causing your body to produce sweat in an attempt to keep your core body temperature down.
Excess sweating can quickly saturate your clothes, which is not ideal in cold temperatures. This can cause a loss of body heat, making you more susceptible to a cold-related injury and further complications.
When you are going to be outside in cold temperatures, it is best to dress in layers and adjust according to the activity and your body’s physiological responses throughout the workout.
It’s no secret that the intensity of your workout plays a role in the amount you sweat. The higher the intensity, the more you will sweat. This means you will have to drink more to replace the fluid that was lost through sweat.
A study was conducted to determine how workout intensity is affected by temperatures. Results concluded that the energy output of a workout is higher in cold weather rather than warm weather due to the amount of clothing worn.
This further highlights the importance of making sure you dress appropriately for the activity you are doing. The more intense the workout, the less clothing you should wear to decrease the amount you sweat.
Reduced fluid intake
When the temperatures are cold, it can be more challenging to hydrate yourself because you simply don’t feel as thirsty.
In the winter, your sweat evaporates much faster due to the cold dry air. Sweat is typically an obvious cue to us that we are losing fluid and need to drink water. However, with the fast evaporation of perspiration, we are less likely to notice this cue.
It is safe to say that staying hydrated in cold temperatures is just as essential as on a scorching summer day. Your hydration status in cold weather is dependent upon multiple factors, and further studies need to be conducted to determine which factor is the greatest cause of dehydration in cold weather. It is important to be aware and stay on top of your hydration status during the colder months since your body is not providing obvious cues that indicate dehydration.
About the Author
Ann Gardner is a 2020-2021 Dietetic student intern who completed her final undergraduate year at the University of Cincinnati in preparation to become a Registered Dietitian Nutritionist. INFINIT Nutrition is proud to partner with the University of Cincinnati's Coordinated Program in Dietetics (CPD) to provide our next generation of nutrition professionals an opportunity to spend time with the INFINIT Team and gain real-life experience working at a sports nutrition company.
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