Occurs to those who sweat profusely and replace fluid losses with water
May occur during exercise, but more common during rest several hours later
Typically does not involve enough muscle mass to cause rhabdomyolysis
May occur during exercise, but more common during rest several hours later
Heat cramps
Nausea and vomiting 
Heat edema
Nausea and vomiting
Heat exhaustion
Constipation
Heat tetany
Constipation 