2020 Volume 35 Issue 1 Pages 17-21
[Purpose] To clarify the relationships between muscle strength at various joint angular velocities and postural control. [Participants and Methods] The knee extensor strength and power output levels of 70 healthy male adults were measured at joint angular velocities of 0, 60, 90, 120, 180, 240, and 300 deg/sec to analyze the relationships between these values and cushion factors and total center-of-pressure (COP) locus lengths when performing one-leg drop jump landing. [Results] With an increase in the joint angular velocity, muscle strength significantly decreased, whereas muscle power output significantly increased. Furthermore, muscle strength and power output at a joint angular velocity of 90 deg/sec or higher were negatively correlated with the cushion factor and total COP locus length. [Conclusion] Although muscle strength tends to be measured under isometric conditions or at low velocities in clinical environments, the results of the present study indicate the importance of such strength at intermediate or higher velocities for instantaneous postural control, suggesting muscle power output at these velocities to be a parameter.
