Your body also directs more of your blood to your skin, which is why you may look flushed when you're hot. When you body overheats, it begins to try to cool off. While your body is trying to cool itself off, other jobs your body must do may not get done. Generally, symptoms start out mild, but grow serious if left unmonitored and untreated. Early symptoms include reduced mental and physical performance.
Heat rash can result from sweaty skin.
More severe cases of heat strain can result in heat-induced fainting or loss of consciousness. Dehydration and circulatory strain from diverted blood flow can lead to heat exhaustion. Dizziness, headaches, nausea, general confusion, and a loss of strength are serious signs of heat exhaustion and should be given immediate attention. Ignoring these warning signs can lead to heat stroke. When heat stroke occurs, the body loses its capacity to cool itself and completely shuts down.