Summer running has us working up a sweat. But between humidity and heat and lack of shade it’s really easy to go from “this is a run workout” to “I’m miserably hot—and dehydrated” fast. This is why it’s important to know just how to get the body used to running in the heat.
For those who live in areas with changing temperatures with each season, it’s easy to want to get outside for a run once the weather warms up. But if you live on the East Coast of the United States you know that it can go from mild, yet still chilly spring to full blown summer temperature in a day.
It takes at least five and up to 10 runs that last an hour or more to get used to the heat. The good news is that cardiovascular adaptations begin within the first three to five days of running.
The Body During A Summer Run
It’s important to understand what is happening biologically when running in the summer heat to prevent dehydration or heat stroke.
Ever notice that your heart is beating faster and you struggle for oxygen more during a run in the heat? This is because oxygen uptake increases when exercising in the heat.
During the summer there are higher temperatures, plus the runner is faced with solar radiation from the sun, and the humidity in the air. Not only that, but solar and thermal radiation also is reflected from the ground. This all further adds to the increase core body temperature, which is already increasing from running.
The body needs to cool down. This is where conduction and evaporation comes in, where the heat produced in the muscle is released by the sweat glands, which then is evaporated from the skin.
Once your body is acclimated to running in the heat it will be better at managing body temperature. This means you will sweat sooner to cool core temperature and the number of sweat glands activated will be increased.
Your heart rate will also not increase as much, yet blood volume will increase to oxygenate the muscles for better performance.
Tips For Beating The Heat
- Run Early or Run Late. The best way to get a good run in during the summer is to beat the beat. Wake up early before the sun rises or after the sun sets when it is the cooler parts of the day. Try to limit the time spent sweating in the sun when it’s the strongest, from noon to 3 pm.
- Hold Back. Scale back on intensity those first few runs to better get acclimated to the heat. Slow down the pace to not go out too aggressive and find your cardiovascular system can’t keep up with the change. Expect performance to degrade 10 percent when running in 86 degrees F.
- Drink up. Hydrate, hydrate, hydrate. Before, during and after the run. You need extra fluids for summer running because you sweat more. Also make sure replenish your elctrolytes. Now is the time for Nuun or Kramp Krusher.
- Dress Right. Now is not the time to layer up. Think light running clothes with plenty of breathability and moisture-wicking properties. You may also want to wear sunglasses or a hat to be able to see when the sun is bright. Apply sunscreen before a run to prevent sunburn. I even recommend having a running belt or vest for even short runs to have water and electrolytes on hand in case of emergency on those really hot days.
- Avoid High Humidity Days. Running in the heat is possible and doable. It isn’t as difficult once you are acclimated to it. But avoid running on days where it is both hot and very humid. If it is 85 degrees F outside but with 100% humidity, it will feel like 108 degrees. This temperature as an increased risk fo heat exhaustion. But if it is 95 degrees F out with 80 % humidity, it will feel like 136 degrees out and anything over 130 degrees F means heat stroke is very likely.
Signs Of Heat Stroke
These tips will help you get used to running in the heat. But they also will help prevent against heat stroke, which is a very serious medical emergency and can be life threatening.
Some runners experience muscle cramps when running in the heat. This warning sign isn’t cause for immediate alarm. It’s common to feel thirsty and sweat a lot when running in the heat. The problem starts when you start sweating too much, with the skin becoming pale and cool. You might start to feel tired and weak. These are sign of heat exhaustion and you need to immediately stop the run, find some shade, sit down, cool down and hydrate. Go inside somewhere with air conditioning or immediately cool off in the shower. If managed right, there is no need to call for emergency help.
The danger is present when this leads to chills or goose bumps, the loss of sweating, dizziness, and a headache. These are serious warning signs of heat stroke. These symptoms then also include confusion, dry skin and a rapid pulse. It’s important to call 911 or for help, to drink water and pour water over the head and body to cool off. Wait somewhere cool and out of the sun for medical attention.
Make sure to check out my ebook Running From Covid19 to get more tips about running outside during the pandemic including whether or not you need to run with a mask.