Large swaths of the world are sweltering amid a scorching hot summer. July is shaping up to be the Earth's hottest month in recorded history, with heat waves expected to become more frequent and unrelenting.
Allowing your body to experience heat through these repeated and controlled exposures, especially if you're doing physical activity, can trigger physiological adaptations that improve your ability to withstand hotter temperatures and can help lower the risk of heat-related illness and death, he said.
"If you wait until the heat wave is upon us and it's extremely severe, it's probably too late and people should try to stay in air-conditioned environments," Kenney said. "The best way to safely tolerate those heat wave conditions would be to prepare for them by heat acclimating ahead of time.