Shock Attenuation in Landing

Shock Attenuation in Landing by Bryon Christopher Applequist Dr. John Mercer, Examination Committee Chair Associate Professor of Kinesiology University of Nevada, Las Vegas Shock attenuation (SA) has been well studied in activities such as walking and running (Chu, et al. 2004; Derrick, et al. 2004; Mercer, et al. 2003); however, there is a lack of research regarding SA during landing. Furthermore, there is lack of information regarding which structures attenuate shock. The purpose of this study was to examine SA among the leg-hip, hip-head, and leg-head segments during landing. Each subject (n=10, Age 26.3 ± 2.71 years, Height 1.68 ± 0.08 m, Mass 70.49 ± 16.03 kg) was instrumented with accelerometers at the leg, hip and forehead. Subjects then performed landings from three heights: 30cm, 60cm, and 90cm. For each height, subjects completed 5 landing trials. Rest was provided between each trial. Order of conditions was randomized to account for fatigue and learning. During each landing, accelerations were recorded at 1000 Hz for the leg, hip, and head respectively using light-weight accelerometers. Data