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Background: Successful recovery from a lower extremity (LE) injury is especially important when it affects our Service men and women, who may have sustained their injury fighting for our freedom. Understanding the interaction between increased task complexity, expected of a U.S. military member, and LE movement, as evidenced by initial and maximum joint angles and vertical ground reaction forces, will allow us to understand injury risk among this population. Purpose: Investigate LE biomechanics of amateur marksmen when asked to complete dual focus shooting tasks. Methods: Vertical ground reaction force (vGRF) and knee biomechanics were measured through the use of force plates and a digital motion capture system respectively. Participants were marked with 38 external anatomical markers and asked to complete a landing task, jumping from a box (31 cm height) onto two force plates half of their height in front of them. Participants completed the landing task under a baseline and a cognitive condition as they completed a shooting task with an AR-15 laser rifle. We hypothesize that participants will display decreased knee flexion and increased vertical ground reaction forces in their dominant leg during the shooting task with an added cognitive load, which requires a greater level of dual tasking. Main Outcome Measures: Vertical ground reaction force and joint angles. Paired samples t-tests were conducted to determine the impact of dual tasking on joint kinematics and kinetics. Alpha level was set at

Background: Jump landing is a major contributor to overuse injuries in figure skaters. Previous research has examined the differences in barefoot jump landing biomechanics of figure skaters and nonskaters; however, differences between figure skaters landing barefoot and in skates has not been evaluated. Purpose: The purpose of this study is to compare landing mechanics among figure skaters while barefoot and in skates, and to describe the landing mechanics of figure skaters. Methods: A total of 10 female figure skaters (age = 19 ± 1.3 yrs, height = 164.7 ± 4.7 cm, weight = 64.4 ± 9.6 kg) were asked to perform a backwards jump landing task and land on their dominant leg in the single-leg figure skater landing position. Inertial measurement units (IMUs) were secured to the landing leg and trunk of each participant. The task was performed under two conditions: barefoot and in skates. Main outcome measures: Peak vertical ground reaction force (vGRF), time-to-peak vGRF, and lower extremity joint angles at peak vGRF. Results: Time-to-peak vGRF was significantly faster during the in-skates condition when compared to the barefoot condition. All other variables were not significant between conditions. Conclusions: Figure skaters do not change their landing mechanics while barefoot compared to while wearing skates. Lack of articulation through the foot when in a skating boot can lead to a shorter time to dissipate vGRF, which can increase the risk of lower extremity injuries in figure skaters.