Improved Ankle Mobility After a 4-Week Training Program Affects Landing Mechanics: A Randomized Controlled Trial

Autor: Jamie S North, Theodoros M. Bampouras, Mark Waldron, Louis P. Howe
Rok vydání: 2020
Předmět:
Zdroj: Journal of Strength and Conditioning Research. 36:1875-1883
ISSN: 1064-8011
DOI: 10.1519/jsc.0000000000003717
Popis: Howe, LP, Bampouras, TM, North, JS, and Waldron, M. Improved ankle mobility after a 4-week training program affects landing mechanics: a randomized controlled trial. J Strength Cond Res XX(X): 000-000, 2020-This study examined the effects of a 4-week ankle mobility intervention on landing mechanics. Twenty subjects with restricted ankle dorsiflexion range of motion (DF ROM) were allocated to either a strength training only (n = 9) or a strength training and ankle mobility program (n = 11). Subjects performed a weight-bearing lunge test and bilateral drop-landings before and after the intervention. Normalized peak vertical ground reaction force (vGRF), time to peak vGRF, and loading rate were calculated, alongside sagittal-plane initial contact angles, peak angles, and sagittal-plane joint displacement for the ankle, knee, and hip. Frontal-plane projection angles were also calculated. After the intervention, only the strength and mobility group improved ankle DF ROM (mean difference = 4.1°, effect size [ES] = 1.00, p = 0.002). A one-way analysis of covariance found group effects for ankle joint angle at initial contact (p = 0.045), ankle (p < 0.001) and hip joint angle at peak flexion (p = 0.041), and sagittal-plane ankle (p < 0.001) and hip joint displacement (p = 0.024) during bilateral drop-landings. Post hoc analysis revealed that the strength and mobility group landed with greater ankle plantarflexion at initial contact (mean difference = 1.4 ± 2.0°, ES = 0.46) and ankle dorsiflexion at peak flexion (mean difference = 6.3 ± 2.9°, ES = 0.74) after the intervention, resulting in a greater ankle joint displacement (mean difference = 7.7 ± 4.0°, ES = 1.00). However, the strength training only group landed with increased peak hip flexion (mean difference = 14.4 ± 11.0°, ES = 0.70) and hip joint displacement (mean difference = 8.0 ± 6.6°, ES = 0.44) during post-testing. The findings suggest that changes in landing strategies following the performance of a strength training program are specific to whether restrictions in ankle mobility are considered as part of the intervention.
Databáze: OpenAIRE