title: Gender difference in older adult's utilization of gravitational and ground reaction force in regulation of angular momentum during stair descent.
abstract: Angular momentum of the body is a highly controlled quantity signifying stability, therefore, it is essential to understand its regulation during stair descent. The purpose of this study was to investigate how older adults use gravity and ground reaction force to regulate the angular momentum of the body during stair descent. A total of 28 participants (12 male and 16 female; 68.5 years and 69.0 years of mean age respectively) performed stair descent from a level walk in a step-over-step manner at a self-selected speed over a custom made three-step staircase with embedded force plates. Kinematic and force data were used to calculate angular momentum, gravitational moment, and ground reaction force moment about the stance foot center of pressure. Women show a significantly greater change in normalized angular momentum (0.92Nms/Kgm; p=.004) as compared to men (0.45Nms/Kgm). Women produce higher normalized GRF (p=.031) during the double support phase. The angular momentum changes show largest backward regulation for Step 0 and forward regulation for Step 2. This greater difference in overall change in the angular momentum in women may explain their increased risk of fall over the stairs.
authors.affiliation: Motion Analysis Laboratory, Department of Kinesiology, Texas Woman's University, 304 Administration Drive, P.O. Box 425589, Denton, TX 76204, United States. Electronic address: ksinghal2@hotmail.com.
authors.forename: Kunal
authors.initials: K
authors.lastname: Singhal
authors.affiliation: Motion Analysis Laboratory, Department of Kinesiology, Texas Woman's University, 304 Administration Drive, P.O. Box 425589, Denton, TX 76204, United States.
authors.forename: Jemin
authors.initials: J
authors.lastname: Kim
authors.affiliation: Motion Analysis Laboratory, Department of Kinesiology, Texas Woman's University, 304 Administration Drive, P.O. Box 425589, Denton, TX 76204, United States.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Casebolt
authors.affiliation: Motion Analysis Laboratory, Department of Kinesiology, Texas Woman's University, 304 Administration Drive, P.O. Box 425589, Denton, TX 76204, United States.
authors.forename: Sangwoo
authors.initials: S
authors.lastname: Lee
authors.affiliation: Motion Analysis Laboratory, Department of Kinesiology, Texas Woman's University, 304 Administration Drive, P.O. Box 425589, Denton, TX 76204, United States.
authors.forename: Ki-Hoon
authors.initials: KH
authors.lastname: Han
authors.affiliation: Motion Analysis Laboratory, Department of Kinesiology, Texas Woman's University, 304 Administration Drive, P.O. Box 425589, Denton, TX 76204, United States.
authors.forename: Young-Hoo
authors.initials: YH
authors.lastname: Kwon
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control; D000368:Aged; D000375:Aging; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait / Q000502:physiology*; D006112:Gravitation; D006801:Humans; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D012737:Sex Factors; D011795:Surveys and Questionnaires; D016138:Walking / Q000502:physiology*
keywords: Angular momentum changes; Gait; Gender differences; Human factor engineering; Stair descent transitions