Author(s): HAYASHI, R., Institution: GIFU UNIVERSITY, Country: JAPAN, Abstract-ID: 710

INTRODUCTION:
Recently, velocity-based training (VBT) has gained popularity for monitoring information, such as maximum barbell speed. The VBT is primarily used in exercises that improve the power output in the lower limbs (power cleans, hang power cleans, and hang high pulls). Although the biomechanical characteristics of lower limb kinematics and kinetics during hang power cleaning are understood, the relationship between the maximum barbell velocity monitored by VBT and lower limb kinematics and kinetics remains unclear. This study aimed to clarify the relationship between the maximum barbell velocity calculated using a device that monitors VBT and lower-limb kinematics and kinetics.
METHODS:
The participants were 10 male university students who routinely incorporated hang power clean (60% and 90% of one repetition maximum [1RM] on two force plates [1,000 Hz]) into their weight training. Motion capture systems recorded videos (250 Hz) and calculated the coordinates of the reflective markers attached to the 47 body points and two barbell points. Data from the force plates and motion capture system were used to calculate the velocity, joint moments, and power of each lower-limb joint in a two-dimensional sagittal plane. MoveFactorX was used to calculate maximum barbell velocity. The relationship between the maximum barbell velocity and lower-limb joint kinematics and kinetics (ankle, knee, and hip joints) was investigated using Pearson’s correlation coefficient.
RESULTS:
Our analysis revealed no correlation in the differences observed for maximum joint velocity (ankle, 60%: 0.585, 90%: 0.469, knee, 60%: 0.404, 90%: 0.013, hip, 60%: 0.045, 90%: 0.043), moment (ankle, 60%: 0.145, 90%: -0.078, knee, 60%: 0.086, 90%: 0.277, hip, 60%: -0.151, 90%: -0.052), and power (ankle, 60%: 0.499, 90%: 0.326, knee, 60%: -0.020, 90%: -1.121, hip, 60%: 0.549, 90%: 0.242) in performing hang power cleans at 60% and 90% of 1RM.
CONCLUSION:
The maximum velocity monitored by the VBT device may inadequately reflect the kinematic variables and kinetics of the three lower-limb joints. The hang power clean pulls the barbell by simultaneously performing dynamic actions on the lower and upper limbs. Therefore, future research that simultaneously examines upper limb kinematics and kinetics could provide a more detailed understanding of the maximum barbell velocity monitored using the VBT device.