Background-Women with anterior cruciate ligament reconstruction have different neuromuscular strategies than noninjured women during functional tasks after ligament reconstruction and rehabilitation.
Objective To compare, landing mechanics and electromyographic activity of the lower extremities during side hopping and crossover hopping maneuvers, in noninjured women and women with anterior cruciate ligament (ACL) reconstruction. Design A case-control study. Setting A 3-dimensional motion analysis laboratory. Participants Twenty-eight young women (range, 21–35 years) (15 control subjects and 13 subjects with ACL reconstruction). Patients and Methods All participants performed a side-to-side hopping task that consisted of hopping single-legged 10 times consecutively from side to side across 2 lines marked 30 cm apart on 2 individual force plates. The task was designated as a side hopping when the hop was to the opposite side of the stance leg and as crossover hopping when the hop was toward the side of the stance leg. Main Outcome Measurements Peak hip-/knee-joint angles; peak knee extension/abduction joint moments; electromyographic studies of the gluteus maximus, gluteus medius, rectus femoris, and hamstring muscles; and quadriceps/hamstring co-contraction ratio were compared between the groups by means of 2 × 2 multivariate analysis of variance tests (group × maneuver). Results Noninjured women and women with ACL reconstruction exhibited similar hip-and knee-joint angles during both types of hopping. Hip-joint angles were greater during the crossover hopping in both groups, and knee-joint angles did not differ between the groups or hops. Knee-joint moments demonstrated a significant group × maneuver interaction. Greater knee extension and valgus moments were noted in the control group during crossover hopping, and greater knee abduction moments were noted in the ACL group during side hopping. Electromyographic data revealed no statistically significantly differences between the groups. Conclusions Women with ACL reconstruction exhibited the restoration of functional biomechanical movements such as hip-/knee-joint angles and lower extremity neuromuscular activation during side-to-side athletic tasks. However, not all biomechanical strategies are restored years after surgery, and women who have undergone a procedure such as ACL reconstruction may continue to exhibit knee-joint abduction moments that increase the risk of additional knee injury.
ObjectivesThe main purpose of the study was to assess the validity between the Fitbit and ActiGraph GT3X+ accelerometer. The specific aims were to determine the: (1) concurrent validity between the various models of the Fitbit and the GTX3+ accelerometer as the criterion measure for: number of steps and active minutes averaged over a single-day and 7-day period; (2) validity of the two devices with the International Physical Activity Questionnaire (IPAQ) for the number of daily active minutes performed.MethodsFifty-three subjects wore a Fitbit and ActiGraph concurrently for 7 days. Data were analysed using correlation coefficients, t-tests to assess mean comparisons and Bland-Altman plots to determine agreement between the Fitbit and the ActiGraph.ResultsThe correlations between the Fitbit and ActiGraph for steps per day and per 7 days were r=0.862 and 0.820, respectively with significant mean differences between both devices. Bland-Altman analyses revealed agreement between the Fitbit and the ActiGraph for 7-day active minutes only. The correlations between the Fitbit and ActiGraph for active minutes per day and per 7 days were r=0.695 and r=0.658, respectively, with no significant mean differences between both devices. No significant correlations were found between the IPAQ and the other two devices.ConclusionsThe data produced by the Fitbit were consistent with the ActiGraph when the means of each device were compared over the 1-day and 7-day time periods. However, Bland-Altman analyses revealed that the Fitbit agreed with the ActiGraph when used to measure physical activity levels over a 7-day span only.
The purpose of this study was to evaluate landing biomechanics in soccer players following ACLR during two landing tasks. Eighteen soccer players with an ACLR and 18 sex-matched healthy control soccer players participated in the study. Planned landing included jumping forward and landing on the force-plates, whereas unplanned landing included jumping forward to head a soccer ball and landing on the force-plates. A significant landing×group interaction was found only for knee flexion angles (p=0.002). Follow-up comparisons showed that the ACL group landed with greater knee flexion during planned landing compared with unplanned landing (p<0.001). Significant main effects of landing were found. The unplanned landing showed reduction in hip flexion (p<0.001), hip extension moments (p<0.013), knee extension moments (p<0.001), and peak pressure (p<0.001). A significant main effect for group for gastrocnemius muscle was found showing that the ACL group landed with reduced gastrocnemius activity (p=0.002). Unplanned landing showed greater injury predisposing factors compared with planned landing. The ACL group showed nearly similar landing biomechanics to the control group during both landing tasks. However, the ACL group used a protective landing strategy by reducing gastrocnemius activity.
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.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.