Heat cramps are painful muscle spasms in the arms, legs and mid-section. One must stop activity and drink plenty of water in order to get better. If not, it will lead to heat exhaustion. Exhaustion is caused by excessive fluid loss. Increased sweating, high body temperature, cool wet skin and some lack of coordination are signs of heat exhaustion.
Heat stroke is extremely serious and can be fatal.
Requires immediate medical attention. Signs include numbness and pale grayish discoloration in the skin. Frostbite can lead to loss of a body part. The victim should get out of the cold to a warm area and get medical attention. Hypothermia occurs when the inner body temperature becomes dangerously low as a result of prolonged exposure to the cold.