Potential relationship between passive plantar flexor stiffness and sprint performance in sprinters.

Objective To investigate the relationship between passive planter flexor stiffness and sprint performance in sprinters. Design Cross-sectional study. Participants Fifty well-trained male sprinters (age: 20.7 ± 1.9 years, height: 175.6 ± 4.9 cm, weight: 66.7 ± 5.1 kg) were participated in this study. Their best personal times in a 100-m sprint ranged from 10.22 to 11.86 s (mean, 11.12 ± 0.43 s). Methods Passive stiffness of the plantar flexors measured using a dynamometer system. Passive stiffness during passive dorsiflexion was calculated from the slope of the linear portion of the torque-angle curve. Results Plantar flexor passive stiffness was significantly correlated with personal best 100-m sprint time ( r  = −0.334, P  = 0.018). Conclusion The present findings suggest that although the relationship between plantar flexor passive stiffness and personal best 100-m sprint time was relatively minimal, a higher plantar flexor passive stiffness may be a potential factor for achieving superior sprint performance in sprinters. Therefore, in the clinical setting, measurement of passive planter flexor stiffness may be useful for assessing sprint performance. [ABSTRACT FROM AUTHOR]