The effects of an unanticipated side-cut on lower extremity kinematics and ground reaction forces during a drop landing

Abstract

Unanticipated direction to cut after landing may alter the lower extremity landing biomechanics when performing landing motions. These alterations may potentially increase the risk of ACL injury. The purpose of this study was to determine if an unanticipated side-cut affects lower extremity landing biomechanics in females. Eighteen recreational female athletes participated in two blocks of testing: the first block of testing consisted of three acceptable trials of anticipated dominant limb and non-dominant limb 45-degree diagonal cutting after landing, which were performed in a counterbalanced order. The second block of testing consisted of three acceptable trials of unanticipated dominant limb and non-dominant limb diagonal cutting after landing. Data analysis mainly focused on the dominant limb landing biomechanics. Unanticipated side-cut landing, compared (paired t-test, p < 0.05) to the anticipated landings, resulted in less hip abduction and tibial internal rotation angle at initial contact (IC) and a lower maximum ankle inversion angle and a greater maximum knee abduction angle, and knee and hip displacement. Also, greater posterior GRF and a longer time to peak medial GRF were exhibited. These outcomes indicate that athletes may adapt their landing mechanics to land unsafely when encountering an unanticipated event.

Are biomechanical stability deficits during unplanned single-leg landings related to specific markers of cognitive function?

“…Therefore, investigating the TTS under unplanned affordances and the inclusion of individuals with a history of severe injuries of the lower limb may be worthwhile. While other authors found alterations of pGRF, 28,47 we observed not such a effect. Therefore, it can be assumed that the study participants were able to equally absorb the landing impact in both conditions, probably by a sufficient degree of anticipatory muscle activity shortly before ground contact and the avoidance of stiff landings (low joint flexion angles of the lower limb).…”

“…Similar findings were made by other trials. 28,47 Although it seems highly plausible that dealing with the unforeseen circumstances occurring in sports requires substantial cognitive resources (e.g. attention, reaction time or inhibitory control), 39 only one study has investigated the association between cognitive function and unplanned landing stability/success.…”

Design and Validation of Rule-Based Expert System by Using Kinect V2 for Real-Time Athlete Support

“…The same situation is observed in the p values of LR movement, indicating a significant change in cognitive abilities before and after the process. Moreover, these results are supported by the d values shown in pair 3, pair 6, pair 9, pair 12, pair 15, and pair 18 of Table 9 as in [42,56].…”

“…Thus, the aim was to examine the weekly physical ability development as stated in [50]. The results obtained from paired t-test are evaluated based on the p value and the effect size (Cohen's d for correlation between two variables) [51] as stated in [42,52]. Independent t-test and effect size were used to examine cognitive ability development by examining changes in joints as weekly pairs from the beginning to the end of the trial period as stated in [53].…”

“…During the process, the average displacement data of the related joints was recorded in each training performed. Thus, the change in the performance of the participants and the effect of the system on physical-cognitive development were analyzed through this data as stated in [42].…”