Differences in Force Gradation between Tug-of-War Athletes and Non-Athletes during Rhythmic Force Tracking at High Exertion Levels

Yen-Ting Lin ； Chia-Hua Kuo ； Yi-Ching Chen

《The Chinese Journal of Physiology》 59卷5期 (2016/10) Pp. 260-267

https://doi.org/10.4077/CJP.2016.BAE411

並列摘要

There is little knowledge regarding the force production capacities of tug-of-war athletes, who undergo years of high-load strength training on handgrip muscles. The purpose of this investigation was to determine the force-grading strategies of tug-of-war athletes by examining force fluctuation properties at high exertion levels. Sixteen tug-of-war athletes and sixteen sedentary non-athletes performed sinusoidal handgrip grip at 50%-100% of maximal effort at 0.5 Hz under visual guidance. Force outputs of the designate task were recorded with a strain gauge. Force fluctuations were separated from the rhythmic output of the target rate in the handgrip force. In addition to a comparable normalized tracking error, the tug-of-war athletes exhibited a greater mean force output (Fmean) and a higher ratio of mean force output (Fmean) to body mass than the non-athletes. The athletes also had lower approximate entropy (ApEn) and a lower mean frequency of force fluctuations than the non-athletes, despite a similar relative size of force fluctuations for the two groups. The scaling of the fundamental element (force pulses) of force fluctuations was also group-dependent, with a greater pulse gain (duration-amplitude regression slope) than the non-athletes. The tug-of-war athletes exhibited superior force-generating capacity and more economic force-grading as compared with the non-athletes, without additional costs to task accuracy and force steadiness, during a highly-demanding rhythmic force task.

並列關鍵字

force variability ； isometric contraction ； regularity

參考文獻

Carroll, T.J.,Barry, B.,Riek, S.,Carson, R.G.(2001).Resistance training enhances the stability of sensorimotor coordination.Proc. Biol. Sci..268,221-227.

Chen, Y.C.,Lin, Y.T.,Huang, C.T.,Shih, C.L.,Yang, Z.R.,Hwang, I.S.(2013).Trajectory adjustments underlying task-specific intermittent force behaviors and muscular rhythms.PLoS One.8,e74273.

Christou, E.A.(2005).Visual feedback attenuates force fluctuations induced by a stressor.Med. Sci. Sports Exerc..37,2126-2133.

de Koning, F.L.,Vos, J.A.,Binkhorst, R.A.,Vissers, A.C.(1984).Influence of training on the force-velocity relationship of the arm flexors of active sportsmen.Int. J. Sports Med..5,43-46.

De Luca, C.J.(1985).Control properties of motor units.J. Exp. Biol..115,125-136.