Heat and Hydration
I went backpacking this weekend in unexpected temperatures of 85 degrees above 8,000ft. Luckily with our late snow pack there was plenty of water, but I still felt the burden of trying to stay hydrated in a hot, arid climate. It got me thinking about hydration and why it is so personal. How can what works for one not work for another? Well, we are not robots and we all need to figure out our own personalized nutrition. Without having a lab to explore your personal needs, we can explore the general needs of an active human and go from there, making tweaks to how we respond in different conditions. Still, the question remains: what is involved in hydration and how do we hydrate on a cellular level?
Water is the fourth macronutrient and the most critical one. Our bodies are comprised of 60% water and our brains are over 75%. Chronic low-level dehydration can lead to many health problems like high blood pressure and reduced kidney function. We obtain 20% of our water needs from food while the rest must come from fluids. We all know to bring water when we exercise but how much do you need? The rule of thumb without exercising is to drink the same amount of water (in mL) as kcals you take in, but most likely you are not keeping track. Again, there is no one size fits all with hydration; needs are very personal based on activity and sweat response, age, hormones etc. The average recommendations are 90oz or 2.6 L for women and 125 oz and 3.5 L for men. Signs of acute dehydration range from nausea, dry eyes, mouth, or lips, to feeling dizzy or light headed.
IT was HOT out there!
When you are exercising this summer, begin thinking about hydration prior to activity to make sure you are getting the minimums listed about for you weight or sex. Then, two to three hours prior to activity drink an additional 16 oz or 500ml of water and 15 min before the activity an additional 8oz or 250ml. During the activity it is important to consume 4 oz every 15-20 min (about 3 to 4 big gulps). Adding electrolytes to your water helps your body absorb the precious fluid so think about adding salt, lemon, lime and orange juice to your water or an electrolyte powder of your choosing.
If dehydration happens, high water content food like fruits, broths, and vegetables assist in rehydrating on the cellular level.
This explains why when I am backpacking the fresh foods taste best: I am hydrating my cells!
Some other tips:
You’ll sweat less at lower intensity, so if you start to feel dehydration symptoms, slow down.
Fill bottles with water and ice so that as you go, the ice melts. If you wear a hydration vest with front pockets for water, that will also help keep your core cool.
It takes a couple of weeks to physiologically adapt to heat, so don’t fret if you feel bad at the beginning of hot weather; it will get better!
When in doubt, plan your routes around alpine lakes. :)
Enjoy the summer activities and stay safe and hydrated!
