Body aches and heat exhaustion: what to know

Heat, exertion, and sweating remove water and salts from the body. Fluid loss can leave muscles tired, cramp-prone, or achy and may occur with excessive thirst, headache, dizziness, or reduced and darker urine. Heat intolerance means becoming uncomfortably hot more easily, but it does not by itself confirm heat exhaustion. A person can become unwell during outdoor work, exercise, travel, or a poorly ventilated setting.

Stop the activity and move to a cool, shaded or air-conditioned place. Loosen extra clothing, use cool wet cloths or a fan, and sip water or an oral rehydration drink if you are alert and able to swallow. Rest and avoid returning to heat or strenuous exercise until fully recovered. Do not give fluids to someone who is confused, vomiting repeatedly, or unable to swallow; place them safely and seek emergency help.

Get urgent medical help if symptoms do not improve promptly with cooling and fluids, or if there is confusion, fainting, seizure, severe weakness, trouble breathing, chest pain, or inability to drink. Very hot skin, altered behaviour, or collapse can signal a life-threatening heat illness. Dark urine with severe muscle pain or weakness also needs prompt assessment.

Could fluid loss or another illness explain the aches? When can I safely return to exercise or outdoor work? Do my medicines or health conditions increase sensitivity to heat?