On a hot sunny day in July you are biking on a trail near Moab, Utah. You come across someone who is on the ground, nearly passed out. You identify heat exhaustion as the problem. You fan the body. This is useful because:
1) It helps to cool down the body and prevent further heat-related complications.
2) It helps to increase blood circulation and oxygen supply to the brain.
3) It helps to reduce the risk of dehydration and heat stroke.
4) It helps to alleviate symptoms of heat exhaustion and promote recovery.