When you run, you sweat, or at least I hope you do. How it works is that the sweat cools our body down when it evaporates off our skin. That's the problem with humidity. Because the moisture content is so high, the sweat just sticks around. Couple that with a lack of breeze, and you're not going to have any hope of cooling down, at least not to the extent you would on a day with less humidity.
I also struggle to breathe with humidity, seriously struggle. Even people with healthy lungs can find some small amount of restriction to their airways, but people with traditional Asthma or Exercise Induced Asthma will really feel it, because the elevated heat causes airway constriction just as cold dry air. I can go do a five mile run on an inside track with air conditioning, and feel great. But even late at night, a two and three quarter mile run leaves me gasping for breath. Even running a full mile without stopping is hard because within minutes of starting, my chest and shoulders get sore from trying to hard to pull air into my lungs. It makes for a miserable run if I don't use my inhaler. So if you have one, be sure to use it prior to your run!
On top of that, it can be very dangerous, even for those conditioned to run in the heat like this. Choose to run during the cooler parts of the day such as early morning or, if you feel safe doing so, after sun set. If all else fails, you can run on a treadmill or an indoor track. That is unless you are stubborn like me! I insist on running outside, no matter how much I hate the humidity because I get absolutely bored to tears on an indoor track, and end up psyching myself out into a bad run.
Most of all, try to be patient with yourself. I know that I get incredibly frustrated this time of year when I am unable to run as far, as fast, or as long as I do during the cooler seasons. I often feel like I am regressing instead of making the progress that I was hoping for. At least until I run on an indoor track, and realize that pushing myself through the humidity has actually helped condition me to be stronger. It is so hard to feel the progress you are making in the miserable temperatures of summer, but I can promise you that if you are running regularly, you ARE making progress. Humidity just does a really good job of hiding it.
Which brings me to my final point. The really big issue with heat and humidity is not how it affects your run quality, though my frustration would say otherwise, but it is instead the danger of heat related illness. If you've ever had a bad night of cramping after a run during a hot day, you have experienced Heat cramps. They can come on during or after a run, and they are miserable. I had one last year that pretty much left a knot in my leg for three days. If you're having these cramps, I would highly suggest some Gatorade and a banana. Nothing helps heat cramps more, at least in my experience! Before your next run, be sure to charge up on fluids, because heat cramps can easily become something worse.
Heat exhaustion, though scary, usually doesn't require a trip to the ER, yet it is not to be taken lightly. Without treatment it can progress quickly to heat stroke. If you suspect heat exhaustion then it is time to stop. Go inside into a cooler area, or if possible, a place with air conditioning. Drink lots of fluids, but avoid caffeinated drinks or alcohol which can dehydrate you further. Remove any unnecessary clothing as well as shoes and socks. A cool shower, ice packs, ice towels, or other cooling measures would also help. Heat exhaustion can also last more than a couple of days, so take it easy for a while and let your body recover!
- Severe muscle cramps
- Drenching sweat and clammy skin
- Slow/Weak heartbeat
- Nausea and vomiting
- Flushed or dry skin
- Lack of sweating
- Increase in urination
- Shortness of breath
- Elevated body temperature
- Confusion or delirium
- Loss of consciousness