Heat illness--a review of military experience (Part 1).

This paper is the first part of a two part review of the published literature reporting the military experience of heat illness. It summarises current concepts of the mechanisms for the development of heat illness. The reports of heat illness in the military medical literature from pre-World War 1 to the end of World War 2 are discussed. The second part will consider reports from the end of the Second World War to the present day. Epidemiological evidence for the factors causing heat illness will be summarised and finally the current areas of uncertainty will be identified with proposals for future research.