A heat wave can be dangerous because as our body temperature rises due to persistence in a hot environment, our vital body functions—such as enzymes and organs—begin to malfunction. This leads to organ failure, and if untreated, can be lethal. Higher temperatures, higher humidity or longer exposure time in heat directly impacts the risk of overheating and the associated complications.
Any extreme of temperature—cold or hot—requires special adaptations to stay safe. In the cold, we can shiver to generate heat and we can put on layers of clothing and find a heat source. In the heat, however, the options to cool are more limited. We sweat to help lower our body temperature, but this effect is limited. We can wear lighter clothing, move activities to cooler indoor environments and drink fluids to maintain our ability to sweat effectively.
Keeping cool and safely hydrated is most important. Avoiding activity in the hot environment will help to prevent a dangerous rise in body temperature, but if unavoidable you should monitor—or have others monitor—your behavior and performance to assess if you need to be cooled.
Can you exercise during a heat wave?
You want to stay inside in the air conditioning during peak heat hours. However, you can still exercise as long as the indoor space is cool or air conditioned or the outdoor environment is cool, such as in the morning. This will mitigate a rise in your body temperature.
How much should we hydrate?
Maintaining adequate hydration is important, but it is equally important not to overdo it. When we sweat, we lose salt and water, and if we only drink water without electrolytes we run the risk of lowering our body sodium to concerning levels. Eating regularly along with drinking water or drinking electrolyte-containing beverages should help to reduce the risk of developing hyponatremia [low sodium in the blood].
Can what we wear help us stay cool?
Yes. Light-colored clothing tends to reflect sunlight and helps keep your body cool. Lightweight and loose-fitting clothing allows air currents to accelerate sweat evaporation—an important form of cooling.
What should we do if we develop symptoms of a heat-related illness?
One of the primary symptoms of heat-related illness is altered mental status, which can manifest as confusion or lethargy. In these cases, consulting a doctor is critical to preventing short- and long-term complications.
Lewis Nelson, chair of the department of emergency medicine at Rutgers University-New Brunswick,