Influence Of Running Surfaces On The 3D Kinematics And Kinetics Of Lower Extremity During Running

Objective: Running is one of the most popular sports activities.Running surface is a potential risk factor among many biomechanical factors that affect the occurrence of running injuries.Different surface materials may affect the kinematic and kinetic changes of lower limbs in running.However,most findings on the kinematics and kinetics of running on different surfaces are controversial.This study aims to explore the kinematic adjustments of the human body in different running surfaces,as well as the basic characteristics of lower limb joint kinetics and plantar pressure changes caused by these adjustments.Methods: A total of 32 male running volunteers(mean age 24.3 ± 2.4 years old,height 172.3 ± 5.8 cm,weight 68.5 ± 2.1 kg)were recruited in this study for a running test on four ground types(concrete,rubber,turf,and EVA(Ethylene Vinyl Acetate)foam)constructed in the laboratory at a speed of 3.33 m/s.A 10-camera Vicon infrared motion capture system was used to collect the kinematic data during running.The sampling frequency was set as 200 Hz.A 3D force platform was used to measure the 3D ground reaction force,and the sampling frequency was set as 2000 Hz.Vicon Nexus and Visual 3D software were used to process and obtain the 3D joint angle,angular velocity,and joint moment of the hip,knee,and ankle joints during running,as well as the ground reaction force of the anterior–posterior,medial–lateral,and vertical directions.All data were expressed as mean ± SD,and SPSS 20.0 statistical software was used for statistical analysis.Repetitive variance measurements were applied to compare the differences in lower limb kinematic and kinetic parameters among different running surfaces.Bonferroni test was adopted for multiple comparisons.The level of statistical significance was determined as p < 0.05.Results:1.No significant difference was observed in the peak angle of the hip,knee,and ankle joints in the sagittal,coronal,and horizontal planes during running on the four different surfaces.2.The maximum adduction angular velocity of the concrete ground on the coronal plane of the hip joint was statistically significantly lower than that of the turf ground(p = 0.023).On the sagittal plane of the ankle joint,the maximum plantar flexion angular velocity of the EVA foam plate ground was statistically significantly lower than those of concrete(p = 0.017)and rubber(p = 0.019)grounds.3.On the sagittal plane of the hip joint,the contact angle of the rubber ground was statistically significantly different from that of the EVA foam plate ground(p =0.012),with a large hip flexion angle on the EVA ground.4.On the sagittal plane of the knee joint,the maximum stretching moment of the concrete ground was statistically significantly lower than those of turf(p = 0.003),rubber(p < 0.001),and EVA(p < 0.001)grounds.Regarding ankle moment,the maximum dorsal flexion moment on the EVA ground was statistically significantly lower than those on turf(p = 0.039)and rubber(p = 0.001)grounds.Meanwhile,themaximum plantar flexion moment on the EVA ground was statistically significantly lower than those on concrete(p < 0.001),rubber(p < 0.001),and turf(p < 0.001)grounds.On the concrete ground,the maximum inversion moment was statistically significantly lower than that on the EVA ground(p = 0.04).The maximum eversion moment was statistically significantly higher than those on turf(p = 0.021),rubber(p= 0.044),and EVA(p = 0.026)grounds.The maximum external rotation moment was statistically significantly higher than those on rubber(p = 0.032)and EVA(p = 0.029)grounds.5.In the anterior–posterior directions,the maximum ground reaction force of the concrete ground was statistically significantly lower than that of the rubber ground(p= 0.033).The minimum ground reaction force of the concrete ground was statistically significantly higher than those of turf(p < 0.001),rubber(p <0.001),and EVA(p =0.001)grounds.In the medial–lateral directions,the maximum ground reaction force on the concrete ground was statistically significantly lower than those on rubber(p =0.021)and EVA(p = 0.012)grounds.In the vertical direction,the maximum ground reaction force on the concrete ground was statistically significantly lower than that on the rubber ground(p = 0.027).The first peak ground reaction force on the EVA ground was statistically significantly higher than those on concrete(p = 0.028)and turf(p = 0.011)grounds.The first peak impulse on the EVA ground was statistically significantly higher than those on concrete(p = 0.005),turf(p < 0.001),and rubber(p= 0.002)grounds.Conclusion: On the EVA ground,the peak angle of hip flexion at the contact ground was higher than other ground,and the maximum metatarsal flexion angular velocity of ankle joint was lower than other ground.It was indicated that in extremely soft ground,the deformation was larger,the velocity of elastic potential energy converted to kinetic potential energy was slowly.When leaving the ground,the velocity of metatarsal flexion was lower.Therefore,running on extremely soft ground was inefficient.The neuromuscular system would pre-activate to adjust the stiffness of the lower limbs when touching the ground.The ankle joint absorbs a lot of kinetic energy on the concrete ground,resulted in a higher load of the ankle joint.On softer floors,in order to achieve the same speed as hard ground,the knee joint would produce a larger peak knee extension moment,resulted in a higher load bearing of the knee joint.