Biomechanical changes of the lower limbs in table tennis players with different foot contact patterns of table tennis forehand loop
BACKGROUND:Exploring the effects of foot contact patterns based on footwork on the joint movement characteristics of human lower limbs in table tennis can provide a scientific basis for guiding lower limb training.OBJECTIVE:To analyze the differences in kinematic and kinetic characteristics of table tennis athletes under different ground contact patterns.METHODS:Motion capture system and three-dimensional force platform were used to synchronously collect kinematic and kinetic data of the dominant side lower limb of 17 professional table tennis athletes in normal foot contact pattern and full-foot contact pattern.Paired t-tests were used to analyze the statistical differences in discrete metrics such as joint angles,ground reaction forces,joint reaction forces,and joint moments.Statistical parametric mapping was employed to analyze the statistical differences in continuous time-series data,such as the movement trajectory of the center foot of pressure and the knee joint moments.RESULTS AND CONCLUSION:(1)In the normal foot contact pattern,knee internal rotation,lateral ground reaction force,knee vertical reaction force,and knee extension moment were significantly higher than those in the full-foot contact pattern.(2)In the 89%-91%movement phase of the distance traveled by the plantar center of pressure,the center of pressure in the normal foot contact pattern was significantly farther away from that in the full-foot contact pattern.(3)In the 23%-38%movement phase of the X-axis torque curve,the knee extension moment in the normal foot contact pattern was significantly higher than that in the full-foot contact pattern.(4)In the 8%-18%phase of the Y-axis torque curve,the knee extension moment in the full-foot contact pattern was significantly higher than that in the normal foot contact pattern.By comparing the difference in lower limb biomechanical characteristics between different ground contact patterns and statistical parametric mapping analysis results,the full-foot contact pattern may be an important factor affecting athletes'performance.It is necessary to adjust and practice the touch patterns to avoid the use of full-footed touch patterns to improve the lower limb athletic ability of table tennis athletes.