This article examines the emergence of 'industrial fatigue' as an object of medico-scientific enquiry and social anxiety in early-twentieth-century Britain. Between 1900 and 1918, industrial fatigue research became the basis of a new science of work, which I term 'industrial physiology'. Drawing on François Guéry and Didier Deleule, I argue that industrial physiology is best understood as a science of 'the productive body'. The worker was an object for medico-scientific intervention only insofar as they represented a constituent part of the machinery of industrial labour, while the individual body was, in turn, reimagined as a productive system in microcosm. In this context, industrial fatigue-defined as diminished capacity for productive work-emerged as the emblematic pathology of industrial civilisation. By 1918, it had become the central category in the scientific articulation of a conception of the body in which health was equated squarely with productive capacity.
Keywords: Didier Deleule; François Guéry; industrial fatigue; industrial physiology; productive body.