title: Air assault soldiers demonstrate more dangerous landing biomechanics when visual input is removed.
abstract: Soldiers are subjected to increased risk of musculoskeletal injuries in night operations because of limited visual input. The purpose of this study was to determine the effect of vision removal on lower extremity kinematics and vertical ground reaction forces during two-legged drop landings. The researchers tested 139 Air Assault Soldiers performing a landing task with and without vision. Removing visual input resulted in increased hip abduction at initial contact, decreased maximum knee flexion, and increased maximum vertical ground reaction force. Without vision, the timing of maximum ankle dorsiflexion for the left leg was earlier than the right leg. The observed biomechanical changes may be related to the increased risk of injury in night operations. Proper night landing techniques and supplemental training should be integrated into Soldiers' training to induce musculoskeletal and biomechanical adaptations to compensate for limited vision.
authors.affiliation: Department of Sports Medicine and Nutrition, University of Pittsburgh, PA 15203, USA.
authors.forename: Yungchien
authors.initials: Y
authors.lastname: Chu
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Sell
authors.forename: John P
authors.initials: JP
authors.lastname: Abt
authors.forename: Takashi
authors.initials: T
authors.lastname: Nagai
authors.forename: Jennifer
authors.initials: J
authors.lastname: Deluzio
authors.forename: Mark
authors.initials: M
authors.lastname: McGrail
authors.forename: Rusty
authors.initials: R
authors.lastname: Rowe
authors.forename: Brian
authors.initials: B
authors.lastname: Smalley
authors.forename: Scott M
authors.initials: SM
authors.lastname: Lephart
mesh_terms: D000293:Adolescent; D000328:Adult; D000401:Aircraft; D001696:Biomechanical Phenomena; D006801:Humans; D007869:Leg Injuries / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D010809:Physical Fitness; D014796:Visual Perception / Q000502:physiology*; D016474:Weight-Bearing