| Functional: |
| Low physical fitness |
| Lack of acclimatization |
| Low work efficiency |
| Reduced skin area to mass ratio (eg, large muscle mass, obesity) |
| Acquired: |
| Use of alcohol prior to activity |
| Medications/supplements (eg, stimulants) |
| Dehydration |
| Viral or bacterial infection |
| Previous heat stroke |
| Sweat gland dysfunction |
| Large skin area with burn scars |
| X-ray radiation |
| Congenital: |
| Ectodermal dysplasia |
| Chronic idiopathic anhidrosis |
