Muscle Stiffness and Rate of Torque Development during Sprint Cycling

作者：Watsford Mark^*; Ditroilo Massimiliano; Fernandez Pena Eneko; D'Amen Giancarlo; Lucertini Francesco

来源：Medicine and Science in Sports and Exercise, 2010, 42(7): 1324-1332.

DOI：10.1249/MSS.0b013e3181ce509d

• MUSCLE-TENDON UNIT
• ELASTICITY
• RATE OF FORCE PRODUCTION
• ISOMETRIC TORQUE

WATSFORD, M., M. DITROILO, E. FERNANDEZ-PENA, G. D'AMEN, and F. LUCERTINI. Muscle Stiffness and Rate of Torque Development during Sprint Cycling. Med. Sci. Sports Exerc., Vol. 42, No. 7, pp. 1324-1332, 2010. Purpose: Crank torque (CT) application and rate of CT development (RCTD) are important considerations in sprint cycling. The stiffness of the musculotendinous unit is related to the isometric rate of torque development (RTD); however, this relationship has yet to be examined in sprint cycling. Methods: Maximal isometric torque (MIT) and isometric RTD of the quadriceps were assessed in 21 trained male cyclists (28.7 +/- 9.5 yr, 1.74 +/- 0.08 m, and 67.5 +/- 7.2 kg). Unilateral musculoarticular (MA) stiffness of the quadriceps was quantified using an oscillation test. Further, the participants performed a maximal 6-s sprint to assess peak power output (PO(peak)), peak CT (CT(peak)), peak RCTD (RCTD(peak)), and the crank angles associated with CT(peak) and RCTD(peak). Participants were ranked on MA stiffness properties and were divided into a relatively stiff group (SG) and a relatively compliant group (CG). Results: The SG displayed a significantly higher MA stiffness than the CG (P < 0.05). Furthermore, the SG reported significantly elevated MIT (27%), RTD (26%), and RCTD(peak) (16%) when compared with the CG (P < 0.05), along with trends for increased PO(peak) (7%) and CT(peak) (8%). The angles at CT(peak) and RCTD(peak) were 7% and 12% lower for the SG, respectively (P G 0.05). MA stiffness was significantly correlated with RCTD(peak), MIT, RTD, and PO(peak). Conclusions: Higher stiffness is related to superior RCTD(peak) in trained cyclists during a single sprint. A significant proportion of the variance in RCTD(peak) was attributed to MA stiffness (37%), which was of greater magnitude than the relationship between RCTD(peak) and MIT. Furthermore, the lower CT(peak) angle and RCTD(peak) angle may contribute to a more rapid development of CT. Accordingly, MA stiffness seems to be an important consideration for sprint cycling.

• 出版日期2010-7