5 days ago
- Climate
- South China Morning Post
Why is humid heat so hard to beat? Here's the science behind hot, wet weather
Extreme heat makes it especially hard for your body to cool down, so you need to be extra careful if you exercise or play sports when temperatures are high.
Your brain tries to keep your body within a degree or two of 37 degrees Celsius, and it does so in part by producing sweat (see graphic).
Sweat cannot do its job when your body is creating a lot of heat or it is too hot and humid to cool down. This can cause you to be dehydrated or even get a heat-related illness such as heat exhaustion or heatstroke.
According to Bharat Venkat, an associate professor at the University of California, Los Angeles (UCLA) and the director of the UCLA Heat Lab, heat can affect the entire body, including our hearts and lungs.
The higher the temperature, the harder it is for the body to stay cool. Humidity, the amount of water vapour in the air, plays a big role too.
High humidity makes it feel hotter than the actual temperature because it makes sweating less effective. There is so much water in the air already that the air cannot take up the water in your sweat.
If you want to exercise in the heat, here are some tips to stay safe, according to the United States' Centres for Disease Control and Prevention.
Time your exercise and outdoor activities for the coolest parts of the day.
Try to exercise in the shade as much as possible.
Take frequent breaks.
Drink lots of fluids, and limit drinks that are high in sugar. Do not wait until you are thirsty to drink more.
Exercise with someone so you can check on each other, or pair up with a teammate.
