Sweating is often present in exertional heatstroke. There are two forms of heat stroke; classical heatstroke and exertional heatstroke. This is most commonly caused by heatstroke, burns, extreme sweating, vomiting, and diarrhea. He was suffering from exhaustion and heatstroke and stated he had a near-death experience. In July 2013 three soldiers died from overheating or heatstroke on an SAS selection exercise. Classical heatstroke occurs from extreme environmental conditions, such as heat waves. This contributed to many Confederate soldiers suffering from heatstroke on long marches. The lone American casualty was due to heatstroke. Doug walks away and Susan collapses with heatstroke. The British army had more casualties due to heatstroke than enemy action. Two people died from heatstroke because of the power outage. There was one death, due to heatstroke, and one birth. Smaller whales can die of heatstroke because of their thermal insulation. Some died of heatstroke within sight of the Residency. Exertional heatstroke appears in individuals after vigorous physical activity.