The design of a universal ergometer and its application for determining human power output

Abstract

Since the turn of the century a considerable amount of experimental work has been carried out with a view to determining the efficiency with which man converts the fuel energy of his food to mechanical work. From such work, power output figures for extended durations of working have been accumulated, bicycle ergometers being commonly used to load the subject. However, comparatively few studies have been made on man’s ability to generate power for short periods of time e.g. less than five minutes, and little serious attempt has been made to develop a mechanism which would allow, for a given period of time, maximal power release. In the early 1960’s the need for such data was emphasised by workers attempting to design a successful man-powered aircraft. The aim of this work, which is both analytical and experimental in nature, is firstly to develop the design of an ergometer which will allow a subject to work in a wide variety of ways, some of which should allow the release of relatively large amounts of power. The second aim is to carry out an experimental investigation on such an ergometer, to compare the relative effectiveness of various ways of working, and to produce further data on short term man-power output. Chapters 1 to 4 are devoted to a discussion of material which is felt to be of importance in considering the design of an ergometer, and after a survey of some earlier models in Chapter 5> the more important design features of the ergometer which is the subject of the present work, are discussed in Chapter 6. Particular attention has been paid to the loading device, or brake, as it represents an important innovation. Instrumentation and calibration are covered in Chapters 7 and 8, while details of the experimental work are discussed in Chapters 9 and 10. The experimental results show that there are significant differences in the effectiveness of the various modes of working adopted, and that one in particular allowed the production of greater amounts of power up to two minutes, than have been so far recorded and published. The maximum output recorded, over a period of six seconds, was slightly in excess of 2 H.P.