title: Initiation of movement from quiet stance: comparison of gait and stepping in elderly subjects of different levels of functional ability.
abstract: This study describes how elderly subjects initiate gait, and step from a position of quiet stance. Based on scores from selected standardized tests subjects were placed in either a high (HFL) or low functional level (LFL) group and were asked to initiate gait, step onto a 10 cm high, 1.22 m wide curb and step over a 10 cm high, 9 cm wide obstacle at a self paced speed. Stepping conditions affected the velocity of movement. It was clear that all subjects decreased initiation velocity for both curb and obstacle compared to gait initiation. Swing and stance limb acceleration ground reaction forces and EMG amplitude were modulated according to initiation velocity. Toe clearance was greater for obstacle than curb and gait initiation. Swing toe-off was significantly earlier and there was a trend for obstacle clearance to be greater for the HFL group. Those in the LFL group appear to be at a greater risk for falling due to the possible effect of slower rate of toe-off that could influence toe clearance over the obstacle.
authors.affiliation: Department of Physical Therapy, School of Allied Health Sciences, East Carolina University, Greenville, NC 27858, USA. bruntd@mail.ecu.edu
authors.forename: Denis
authors.initials: D
authors.lastname: Brunt
authors.forename: Valeria
authors.initials: V
authors.lastname: Santos
authors.forename: Hyeong Dong
authors.initials: HD
authors.lastname: Kim
authors.forename: Kathye
authors.initials: K
authors.lastname: Light
authors.forename: Charles
authors.initials: C
authors.lastname: Levy
mesh_terms: D000058:Accidental Falls; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D004576:Electromyography; D005260:Female; D005528:Foot / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000502:physiology; D008297:Male; D009068:Movement / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology