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Examining the effects of a weighted pack on functional movements in smokejumpers
Valerie Moody1, Elise Brady1, Isabella Callis1
1School of Integrative Physiology and Athletic Training, University of Montana, Missoula, MT, USA.
Background:
Smokejumpers are required to parachute from planes, carry gear weighing more than 50 kg, and hike on steep terrain. With a majority of injuries sustained to the lower extremity, it is imperative to understand the influence a weighted pack may have on functional performance.
Objective:
To examine the effects of external load on functional movements in Smokejumpers.
Methods:
Using repeated measures design, ten Smokejumpers completed two trials consisting of 3 movements in weighted (50 kg) and unweighted conditions. Nine males and one female (age of 40.1±8.4 years, mass 81.1±8.3 kg) performed overhead squat, hurdle step and anterior reach. Movements were scored based on established guidelines. The mean of three trials was recorded for anterior reach on both limbs.
Results:
Differences between weighted and unweighted scores in the overhead squat (p = 0.001), ND hurdle step (p = 0.005), D hurdle step (p = 0.000) and overall composite scores (p = 0.006) were found to be significantly different. Differences were also noted in D (p = 0.035) and ND (p = 0.045) anterior reach.
Conclusions:
The addition of a weighted pack negatively influences functional movements in Smokejumpers, which may lead to greater injury risk. Implementation of injury prevention strategies to reduce occupational injury risk should be explored.
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