Differences in Lateral Drop Jumps From an Unknown Height Among Individuals With Functional Ankle Instability.
Autor: | Rosen, Adam, Swanik, Charles, Thomas, Stephen, Glutting, Joseph, Knight, Christopher, Kaminski, Thomas W. |
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Předmět: |
LEG physiology
MUSCLE physiology ANKLE physiology CALF muscle physiology ANALYSIS of variance ANKLE injuries ELECTROMYOGRAPHY EXERCISE physiology JOINT hypermobility JUMPING MULTIVARIATE analysis MUSCLE contraction MUSCLE strength testing NEUROPHYSIOLOGY SPRAINS STATISTICS T-test (Statistics) TIME VISUAL perception DATA analysis NEUROMUSCULAR system CONTINUING education units CASE-control method DATA analysis software DESCRIPTIVE statistics DISEASE complications |
Zdroj: | Journal of Athletic Training (Allen Press); Nov/Dec2013, Vol. 48 Issue 6, p773-781, 9p, 1 Color Photograph, 2 Black and White Photographs, 4 Charts |
Abstrakt: | Context: Functional ankle instability (FAI) is a debilitating condition that has been reported to occur after 20% to 50% of all ankle sprains. Landing from a jump is one common mechanism of ankle injury, yet few researchers have explored the role of visual cues and anticipatory muscle contractions, which may influence ankle stability, in lateral jumping maneuvers. Objective: To examine muscle-activation strategies between FAI and stable ankles under a lateral load and to evaluate the differences in muscle activation in participants with FAI and participants with stable ankles when they were unable to anticipate the onset of lateral loads during eyes-open versus eyes-closed conditions. Design: Case-control study. Setting: Controlled laboratory setting. Patients or Other Participants: A total of 40 people participated: 20 with FAI and 20 healthy, uninjured, sex- and age-matched persons (control group). Intervention(s): Participants performed a 2-legged lateral jump off a platform onto a force plate set to heights of 35 cm or 50 cm and then immediately jumped for maximal height. They performed jumps in 2 conditions (eyes open, eyes closed) and were unaware of the jump height when their eyes were closed. Main Outcome Measure(s): Amplitude normalized electro-myographic (EMG) area (%), peak (%), and time to peak in the tibialis anterior (TA), peroneus longus (PL), and lateral gastroc-nemius (LG) muscles were measured. Results: Regardless of the eyes-open or eyes-closed condition, participants with FAI had less preparatory TA (t |
Databáze: | Complementary Index |
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