During summer months, extreme heat presents a significant health concern for individuals engaging in outdoor physical activity. According to experts at the UCLA Heat Lab, temperatures above 90 degrees Fahrenheit (32°C), especially with high humidity, can push the body past safe limits. The National Oceanic and Atmospheric Administration classifies heat index levels between 90 and 103 degrees Fahrenheit as requiring extreme caution, while values exceeding 103 are categorized as dangerous or extremely dangerous. This is because the body struggles to maintain its normal temperature of 98.6°F (37°C) by producing sweat. When the air contains a lot of moisture, sweat does not dry quickly. This prevents the body from losing heat and staying cool. This can lead to dehydration or more serious conditions such as heat exhaustion and heat stroke.

The Centers for Disease Control and Prevention (CDC) emphasized that heat affects multiple systems in the body, including the heart, lungs, and muscles. Heat-related illnesses often begin with symptoms such as muscle cramps, dizziness, or nausea and can escalate to life-threatening conditions like heat stroke or rhabdomyolysis, a rare disorder involving rapid muscle breakdown. Health professionals advise limiting exercise to cooler times of the day, staying in shaded areas, taking frequent breaks, and drinking adequate fluids. Experts have warned that individuals tend to underestimate the severity of heat stress, which makes self-assessment unreliable. Preventive measures, hydration, and awareness are paramount to avoid heat-related complications during strenuous activity in hot weather.