“I thought I was just having a bad day”: why running at 30°C without 10 to 14 days of acclimatization is a signal your body takes very seriously
That heavy feeling in your legs on your first hot run isn’t poor sleep or stress—it’s your cardiovascular system struggling to cool and fuel your muscles simultaneously. Understanding heat acclimatization science reveals why 10 to 14 days of gradual exposure matters, and how ignoring this timeline puts you at genuine risk.