Influence of the contact time on coupling time and a simple method to measure coupling time

Abstract : The enhancement of performance in stretch shortening cycle (SSC) exercises has been attributed to the recoil of elastic energy stored during the stretching phase and depends on the duration of the coupling time (T(coupling)) i.e., the duration of the isometric phase occurring between the stretch and the shortening of the muscle. However, instead of T(coupling), the contact time (T(contact))--i.e., the sum of T(coupling) plus the duration of the stretching and shortening phases that precede and follow T(coupling)--is more easily and often measured. The aim of this study was to investigate the T(coupling) changes within a large range of T(contact), in order to propose a possible relationship between T(coupling) and T(contact), thus allowing the accurate measurement of T(coupling )only from a tachometer and force data obtained classically in vertical jumps, jumps on sledge apparatus and running on force treadmills. Eleven subjects performed SSC exercises on a sledge apparatus with a large range of T(contact) (400, 700, 1,000, 1,500, 2,000 and 2,500 ms). The T(coupling) and T(contact) values were measured individually, from force platform recordings and the velocity of the carriage seat obtained by a tachometer. For the longest T(contact) (i.e., from 850 to 2,500 ms), we observed a significant linear relationship between T(contact) and T(coupling). This transition between T(contact) shorter or longer than about 850 ms seems to be important and to correspond to T(coupling) close to 300 ms. This limit observed in the present study could be explained physiologically due to a possible modification of the cross-bridges formation.
Document type :
Journal articles
Complete list of metadatas

https://hal.univ-cotedazur.fr/hal-01859286
Contributor : Jean-Benoit Morin <>
Submitted on : Tuesday, August 21, 2018 - 9:03:58 PM
Last modification on : Wednesday, August 22, 2018 - 1:14:43 AM

Links full text

Identifiers

Citation

A Zameziati, J. Morin, E. Deiuri, A. Telonio, A. Belli, et al.. Influence of the contact time on coupling time and a simple method to measure coupling time. European Journal of Applied Physiology, Springer Verlag, 2006, 96 (6), pp.752 - 756. ⟨10.1007/s00421-005-0108-2⟩. ⟨hal-01859286⟩

Share

Metrics

Record views

39