Methodological considerations of task and shoe wear on joint energetics during landing

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Randy J. Schmitz, Associate Professor (Creator)
Sandra J. Shultz, Professor and Chair (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/

Abstract: To better understand methodological factors that alter landings strategies, we compared sagittal plane joint energetics during the initial landing phase of drop jumps (DJ) vs. drop landings (DL), and when shod vs. barefoot. Surface electromyography, kinematic and kinetic data were obtained on 10 males and 10 females during five consecutive drop landings and five consecutive drop jumps (0.45 m) when shod and when barefoot. Energy absorption was greater in the DJ vs. DL (P = .002), due to increased energy absorption at the hip during the DJ. Joint stiffness/impedance was more affected by shoe condition, where overall stiffness/impedance was greater in shod compared to barefoot conditions (P = .036). Further, hip impedance was greater in shod vs. barefoot for the DL only (via increased peak hip extensor moment in DL), while ankle stiffness was greater in the barefoot vs. shod condition for the DJ only (via decreased joint excursion and increased peak joint moment in DJ vs. DL) (P = .011). DJ and DL place different neuromechanical demands upon the lower extremities, and shoe wear may alter impact forces that modulate stiffness/impedance strategies. The impact of these methodological differences should be considered when comparing landing biomechanics across studies.

Additional Information

Publication
Journal of Electromyography and Kinesiology. 2012; 22(1):124-30.
Language: English
Date: 2012
Keywords
Landing energetics, Work absorption, Landing biomechanics, Force dissipation strategies, Footwear

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