Ground reaction forces and knee kinetics during single and repeated badminton lunges

Abstract

Repeated movement (RM) lunge that frequently executed in badminton might be used for footwear evaluation. This study examined the influence of single movement (SM) and RM lunges on the ground reaction forces (GRFs) and knee kinetics during the braking phase of a badminton lunge step. Thirteen male university badminton players performed left-forward lunges in both SM and RM sessions. Force platform and motion capturing system were used to measure GRFs and knee kinetics variables. Paired t-test was performed to determine any significant differences between SM and RM lunges regarding mean and coefficient of variation (CV) in each variable. The kinetics results indicated that compared to SM lunges, the RM lunges had shorter contact time and generated smaller maximum loading rate of impact force, peak knee anterior-posterior force, and peak knee sagittal moment but generated larger peak horizontal resultant forces (Ps < 0.05). Additionally, the RM lunges had lower CV for peak knee medial-lateral and vertical forces (Ps < 0.05). These results suggested that the RM testing protocols had a distinct loading response and adaptation pattern during lunge and that the RM protocol showed higher within-trial reliability, which may be beneficial for the knee joint loading evaluation under different interventions.

Does shoe heel design influence ground reaction forces and knee moments during maximum lunges in elite and intermediate badminton players?

“…A priori power analysis was performed to determine appropriate sample sizes. Effect sizes were calculated from previous research with methods that closely resembled this study [19, 23]. Based on an alpha of 0.05 and 80% power, 11 subjects per group were recruited for this study.…”

“…The force plate was placed at a45-degree position relative to the left-forward direction of the starting positions. A shuttlecock was suspended at a height of 0.6 m with a string, which was 0.6 m from the center of the force plate along the respective lunging directions [19]. …”

“…A total of 21 reflective markers (diameter 14 mm) were attached over the anatomical landmarks [19]: four pelvis markers (left and right ASIS and PSIS), medial and lateral epicondyles of femur, medial and lateral malleolus, two calcaneus markers (posterior upper, posterior lower of calcaneus of the shoe), three shoe tracking markers (medial side of first metatarsal head, upper side of second metatarsal head, and lateral side of fifth metatarsal head), and two four-marker rigid clusters were affixed to the thigh and leg segments. The markers on the medial and lateral malleolus and femoral epicondyles were used for the static trial and were removed during the dynamic trials.…”

“…A fourth-order Butterworth bidirectional filter with a cut-off frequency of 12 Hz was used to smooth the kinematics data [19,27]. The kinetic data was filtered using a fourth order Butterworth filter at 100 Hz [2,27].…”

“…In badminton, players often performed powerful and long-distance lunges having more than 40 degrees of the sagittal footstrike angle [7,16,18,19], which is much larger than heel-toe running having about 20 degrees[11]. Due to this unique sagittal footstrike angle and the location of initial contact, changes in heel curvature design of a badminton shoe might alter impact attenuation during lunge movements.…”