What Exactly Is Heat Stress?
Think of your body as a finely tuned engine. During exercise, it generates a significant amount of heat. To prevent overheating, your body's primary cooling mechanism is sweating. As sweat evaporates from your skin, it takes heat with it, helping to maintain
a stable internal temperature. Heat stress occurs when this system is overwhelmed. This often happens in hot, and particularly humid, conditions where sweat can't evaporate effectively. Your body then has to work much harder, diverting more blood to the skin to try and cool down, which puts a strain on your heart and muscles.
From Exhaustion to Emergency
Ignoring the early signs of heat stress can lead to more serious conditions. The first stage is often heat exhaustion. This happens when your body has lost too much water and salt through sweat. Symptoms include heavy sweating, dizziness, headache, nausea, and cool, clammy skin. While serious, heat exhaustion is usually reversible if you act quickly. However, if left untreated, it can escalate into heatstroke. Heatstroke is a life-threatening medical emergency where the body's temperature regulation system fails completely, causing the core temperature to rise to 40°C or higher. This can cause permanent damage to your brain and other vital organs.
Know the Warning Signs
Being able to distinguish between heat exhaustion and heatstroke can be lifesaving. For heat exhaustion, look for symptoms like fatigue, faintness, excessive thirst, muscle cramps, and a weak, rapid pulse. The person will likely be sweating heavily. With heatstroke, the signs are more severe. The person may stop sweating and have hot, red, dry skin. They may become confused, agitated, or lose consciousness. A rapid heart rate, breathing difficulties, and seizures are also common signs of heatstroke. Any sign of confusion or altered mental state is a major red flag indicating a medical emergency.
Smarter, Safer Summer Workouts
Prevention is always the best strategy. First, stay hydrated by drinking plenty of water throughout the day, not just during your workout. For longer sessions, a sports drink can help replenish lost electrolytes. Time your workouts wisely, opting for cooler parts of the day like the early morning or late evening. Dress in light-coloured, loose-fitting clothing made from breathable, moisture-wicking fabrics to help sweat evaporate. Finally, listen to your body. Reduce the intensity and duration of your exercise, and don't be afraid to take extra breaks. If you feel dizzy or overly fatigued, stop immediately.
What to Do in an Emergency
If you suspect someone has heat exhaustion, move them to a cool, shaded area immediately. Have them lie down and elevate their legs slightly. Encourage them to sip cool water or an electrolyte drink. Applying cool, wet cloths to their skin can also help lower their body temperature. Symptoms should improve within 30 minutes. If they don't, or if the person shows signs of heatstroke like confusion or loss of consciousness, call for emergency medical help immediately. While waiting for help, do everything you can to cool them down rapidly: apply ice packs to the neck, armpits, and groin; sponge them with cool water; or place them in a cool shower or bath.
