Passengers on the London Underground during the heatwave on June 26th
Guy Bell / Alamy
The June heatwave that gripped Europe was historic, following closely on the heels of a record-breaking heat event in May. With another prolonged heatwave underway, temperatures in the UK are soaring to 34°C (93°F).
To explore the impact of this extreme heat, I visited the University of Brighton’s Environmental Extremes Laboratory, located adjacent to the Brighton & Hove Albion Football Club’s stadium. This facility collaborates with athletes to assess fitness levels under various environmental conditions. After merely 10 minutes in their heat chamber, it became clear that most of us are unprepared for the increasing frequency and severity of heatwaves.
The heat chamber features windows that enable researchers to manipulate temperature, humidity, and oxygen levels to mimic the conditions found in high-altitude venues or during European heatwaves.
“Heatwaves are a growing reality, and we need to equip people with the tools to adapt and manage these conditions repeatedly throughout the year,” said lab director Neil Maxwell.
With the temperature set to 35°C (95°F) and humidity at 50%—similar to London’s conditions during June—my heart rate and blood oxygen levels were monitored using a fingertip pulse meter and my skin temperature with an infrared thermometer. Participants were also asked to rate their perceived heat and activity level.
Upon entering the chamber, the heat enveloped me like a wall. What was I about to endure for the sake of science?
To simulate outdoor movement, I walked on a treadmill set at a 1% incline. Sweating commenced immediately, but high humidity hindered evaporation and cooling. Even this moderate activity soon became uncomfortable in the oppressive heat.
After 5 minutes, my skin temperature surged from 33°C to over 36°C. Maxwell mentioned that my body was striving to dissipate heat by circulating warm blood from my core to my skin.
Reporter Alec Luhn in the heat chamber at the University of Brighton’s Environmental Extremes Laboratory.
Bill Norton
My heart rate spiked from 72 beats per minute to 81. As the body sweats and becomes dehydrated, the blood thickens, placing additional strain on the heart.
After 10 minutes of slight exertion, I felt exhausted, with my heart rate reaching 95 beats per minute. I experienced dizziness when Maxwell guided me back to a chair outside the chamber.
I inquired about my performance. “You’re not heat acclimatized,” he informed me. Even those in relatively good shape can be at risk.
Maxwell offered me a strawberry popsicle, which not only tasted delightful but also initiated internal cooling. He then instructed me to submerge my hands in a tub of cold water. The blood vessels in the hands, feet, and ears facilitate quick cooling of the blood flow.
“This method allows us to lower body temperature more efficiently,” Maxwell explained.
Simple actions like a cold shower can be remarkably effective. However, if the water is too cold, the blood vessels constrict. Research by Maxwell and his team indicates that only a small fraction of the UK population takes sufficient precautions against heat exposure. He noted that I arrived without a water bottle, even though it was a warm day.
In the long run, Maxwell emphasizes the need for public education on enhancing heat tolerance. Basic aerobic exercises like jogging improve the heart’s capacity to circulate blood to the skin. Regular heat exposure is also crucial; a personal sauna adjacent to the lab can rapidly expand blood vessels and increase sweat production, all while maintaining electrolyte levels and regulating sweat’s salt concentration.
“We need to redefine the current narrative. Fever can be safe and even therapeutic,” Maxwell asserted.
Upon returning home, I found myself with a headache, feeling hot and parched. I realized I should incorporate more saunas into my routine. As for jogging, I’ll give it my best effort.
Topics:
Source: www.newscientist.com