Volleyball players often land on a single leg following a spike shot due to a shift in the center of gravity and loss of balance. Landing on a single leg following a spike may increase the probability of non-contact anterior cruciate ligament (ACL) injuries. The purpose of this study was to compare and analyze the kinematics and kinetics differences during the landing phase of volleyball players using a single leg (SL) and double-leg landing (DL) following a spike shot. The data for vertical ground reaction forces (VGRF) and sagittal plane were collected. SPM analysis revealed that SL depicted a smaller knee flexion angle (about 13.8°) and hip flexion angle (about 10.8°) during the whole landing phase, a greater knee and hip power during the 16.83–20.45% (p = 0.006) and 13.01–16.26% (p = 0.008) landing phase, a greater ankle plantarflexion angle and moment during the 0–41.07% (p < 0.001) and 2.76–79.45% (p < 0.001) landing phase, a greater VGRF during the 5.87–8.25% (p = 0.029), 19.75–24.14% (p = 0.003) landing phase when compared to DL. Most of these differences fall within the time range of ACL injury (30–50 milliseconds after landing). To reduce non-contact ACL injuries, a landing strategy of consciously increasing the hip and knee flexion, and plantarflexion of the ankle should be considered by volleyball players.
The medial longitudinal arch is considered as an essential feature which distinguishes humans from other primates. The longitudinal arch plays a supporting and buffering role in human daily physical activities. However, bad movement patterns could lead to deformation of arch morphology, resulting in foot injuries. The authors aimed to investigate any alterations in static and dynamic arch index following different weight bearings. A further aim was to analyze any changes in plantar pressure distribution characteristics on gait during walking and stopping, Twelve males were required to complete foot morphology scans and three types of gait tests with 0%, 10%, 20% and 30% of additional body weight. The dynamic gait tests included walking, planned and unplanned gait termination. Foot morphology details and plantar pressure data were collected from subjects using the Easy-Foot-Scan and Footscan pressure platform. No significant differences were observed in static arch index when adding low levels of additional body weight (10%). There were no significant changes observed in dynamic arch index when loads were added in the range of 20% to 30%, except in unplanned gait termination. Significant maximal pressure increases were observed in the rearfoot during walking and in both the forefoot and rearfoot during planned gait termination. In addition, significant maximum pressure increases were shown in the lateral forefoot and midfoot during unplanned gait termination when weight was increased. Findings from the study indicated that excessive weight bearing could lead to a collapse of the arch structure and, therefore, increases in plantar loading. This may result in foot injuries, especially during unplanned gait termination.
Although values of arch stiffness index (ASI) have been used to evaluate arch structure and injury susceptibility, investigations are limited regarding the influence of ASI on biomechanical characteristics during gait termination, which involves a challenging balance transition from walking to standing. This study aimed to explore plantar pressure distribution and lower extremity joint kinematic differences between individuals with both a stiff and flexible arch (SA and FA, respectively) during planned and unplanned gait termination (PGT and UGT, respectively). Following the calculation of ASI, sixty-five asymptomatic male subjects were classified and participated in two types of gait termination tests to acquire kinematic and plantar pressure data. Parameters were compared between SA and FA using a two-way ANOVA during PGT and UGT, respectively. UGT was found to have a larger range of motion on the hip joint in the sagittal plane and the knee joint in the transverse plane when compared with PGT. The differences in the kinematic characteristics of the lower limb joints caused by the difference in arch stiffness are mainly concentrated in the ankle and metatarsophalangeal joints. Plantar pressure data, represented by the maximum pressure, showed significant differences in the forefoot and rearfoot areas. These results suggest that ASI could change freedom of motion of the lower limb joints, and UGT tends to conduct a compensatory adjustment for the lower extremity kinetic chain. An understanding of the biomechanical characteristics of arch structures may provide additional insights into foot function and injury prediction during gait termination.
Backward jump-landing during sports performance will result in dynamic postural instability with a greater risk of injury, and most research studies have focused on forward landing. Differences in kinematic temporal characteristics between single-leg and double-leg backward jump-landing are seldom researched and understood. The purpose of this study was to compare and analyze lower extremity kinematic differences throughout the landing phases of forward and backward jumping using single-leg and double-leg landings (FS and BS, FD and BD). Kinematic data were collected during the landing phases of FS and BS, FD and BD in 45 participants. Through statistical parametric mapping (SPM) analysis, we found that the BS showed smaller hip and knee flexion and greater vertical ground reactive force (VGRF) than the FS during 0–37.42% (p = 0.031), 16.07–32.11% (p = 0.045), and 23.03–17.32% (p = 0.041) landing phases. The BD showed smaller hip and knee flexion than the FD during 0–20.66% (p = 0.047) and 0–100% (p < 0.001) landing phases. Most differences appeared within a time frame during the landing phase at 30–50 ms in which non-contact anterior cruciate ligament (ACL) injuries are thought to occur and are consistent with the identification of risk in biomechanical analysis. A landing strategy that consciously increases the knee and hip flexion angles during backward landing should be considered for people as a measure to avoid injury during the performance of this type of physical activity.
The purpose of this study was to determine relationships between arch stiffness and relative regional impulse during walking, running, and stopping. A total of 61 asymptomatic male subjects volunteered to participate in the study. All were classified by calculating the arch stiffness index using 3-dimensional foot morphological scanning. Plantar pressure distribution data were collected from participants using a Footscan pressure platform during gait tests that included walking, running, and gait termination. The stiff arches group (n = 19) and flexible arches group (n = 17) were included in the following data analysis. The results suggested that subjects with stiffer arches had a larger and smaller percentage of plantar impulse in the forefoot and rearfoot, respectively, than subjects with more flexible arches during walking and running. However, during gait termination, which included planned and unplanned gait stopping, the plantar impulse distribution pattern was found to be reversed. The current findings demonstrate that the distributional changes of plantar loading follow unidirectional transfer between the forefoot and the rearfoot on the plantar longitudinal axis. Moreover, the patterns of impulse distribution are also different based on different gait task mechanisms.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.