Trunk Inclination During Squatting is a Better Predictor of the Knee-Extensor Moment Than Shank Inclination
| Autor: | Jordan Cannon, Christopher M. Powers, Rachel K. Straub, Adam J. Barrack |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Adult
Male Knee Joint Strength training Movement Biophysics Physical Therapy Sports Therapy and Rehabilitation Squat Context (language use) Quadriceps Muscle Young Adult 03 medical and health sciences 0302 clinical medicine Humans Orthopedics and Sports Medicine 030212 general & internal medicine Range of Motion Articular Mathematics Orthodontics Knee extensors Rehabilitation Torso Resistance Training 030229 sport sciences Stepwise regression Trunk Healthy Volunteers Biomechanical Phenomena Moment (mathematics) Kinetics Squatting position Female |
| Zdroj: | Journal of Sport Rehabilitation. 30:899-904 |
| ISSN: | 1543-3072 1056-6716 |
| DOI: | 10.1123/jsr.2020-0397 |
| Popis: | Context: A limitation of previous studies on squatting mechanics is that the influence of trunk and shank inclination on the knee-extensor moment (KEM) has been studied in isolation. Objective: The purpose of the current study was to determine the influence of segment orientation on the KEM during freestanding barbell squatting. Design: Repeated-measures cross sectional. Setting: University research laboratory. Participants: Sixteen healthy individuals (8 males and 8 females). Intervention: Each participant performed 8 squat conditions in which shank and trunk inclinations were manipulated. Main Outcome Measures: 3D kinematic and kinetic data were collected at 250 and 1500 Hz, respectively. Regression analysis was conducted to identify the individual relationships between the KEM and the trunk and shank inclination at 60° and 90° of knee flexion. To identify the best predictor(s) of the KEM, stepwise regression was implemented. Results: Increased shank inclination increased the KEM (P R2 = .21–.25). Conversely, increased trunk inclination decreased the KEM (P R2 = .49–.50). For the stepwise regression, trunk inclination entered first and explained the greatest variance in the KEM (all P R2 = .49–.50). Shank inclination entered second (all P R2 = .53–.54) and explained an additional 3% to 5% of the variance. Conclusions: Our results confirm that inclination of the trunk and shank have an opposing relationship with the KEM. Increased forward shank posture increases the KEM, while increased forward trunk posture decreases the KEM. However, when viewed in combination, the trunk was the superior predictor of the KEM, highlighting the fact that increased quadriceps demand created by a forward shank can be offset by trunk inclination. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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