The mechanical efficiencies of running and bicycling against a horizontal impeding force

Experiments using a horizontal impeding force to determine the apparent mechanical efficiency of subjects running or bicycling on a horizontal treadmill are described.Two treadmills were used for the running experiments, one at Hampstead and one at Oxford. (Some of the results for the Oxford treadmill presented in another paper [10] are included for purposes of comparison.) It was found that the energy cost of unloaded running was significantly lower for the Hampstead treadmill. Possible reasons for this difference are discussed.Apparent efficiencies were calculated as the inverse of the slope of the linear regression of metabolic rate on external work rate × 102. For both running and bicycling, the relation between metabolic rate and external work rate was found to be linear, so that the apparent efficiencies were independent of the magnitude of external loading.The mean value for three well-trainedathletes for apparent load-running efficiency (LRE) at Hampstead was 39.1%. This was not significantly different from the value of 36.1% previously obtained on athletes at Oxford. In addition, there were no significant differences between the LRE values found at Hampstead and Oxford for the two athletes studied on both treadmills.

[1]  B B Lloyd,et al.  The mechanical efficiency of treadmill running against a horizontal impeding force , 1972, The Journal of physiology.

[2]  R. Margaria.  Positive and negative work performances and their efficiencies in human locomotion , 1968, Internationale Zeitschrift für angewandte Physiologie einschließlich Arbeitsphysiologie.

[3]  Henry Monmouth Smith,et al.  Gaseous Exchange and Physiological Requirements for Level and Grade Walking , 2009, Nature.

[4]  G. Cavagna,et al.  Positive work done by a previously stretched muscle. , 1968, Journal of applied physiology.

[5]  E. Asmussen,et al.  Positive and negative muscular work. , 1953, Acta physiologica Scandinavica.

[6]  P. Courau.  [Muscular work]. , 1962, Cahiers de medecine interprofessionnelle.

[7]  P. D. di Prampero,et al.  Standardization of submaximal exercise tests. , 1968, Bulletin of the World Health Organization.

[8]  G. Cavagna,et al.  The mechanics of sprint running , 1971, The Journal of physiology.

[9]  L. Pugh.  The influence of wind resistance in running and walking and the mechanical efficiency of work against horizontal or vertical forces , 1971, The Journal of physiology.

[10]  B. Whipp,et al.  Efficiency of muscular work. , 1969, Journal of applied physiology.

[11]  M. C. Brown,et al.  The effect of stretching a contracting muscle on its subsequent performance during shortening. , 1972, The Journal of physiology.

[12]  G. Cavagna,et al.  MECHANICAL WORK IN RUNNING. , 1964, Journal of applied physiology.

[13]  G. Cavagna,et al.  Mechanics of walking. , 1965, Journal of applied physiology.

[14]  R. Margaria,et al.  Energy cost of running. , 1963, Journal of applied physiology.

[15]  P. Högberg.  Length of stride, stride frequency, „flight” period and maximum distance between the feet during running with different speeds , 2004, Arbeitsphysiologie.

[16]  Brown Mc,et al.  The effect of stretching a contracting muscle on its subsequent performance during shortening. , 1972 .