A1 Journal article (refereed)
Leg extension power and walking speed in very old people living independently (1996)

Rantanen, T., & Avela, J. (1996). Leg extension power and walking speed in very old people living independently. Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 52A(4), 225-231. https://doi.org/10.1093/gerona/52A.4.M225

JYU authors or editors

Publication details

All authors or editors: Rantanen, Taina; Avela, Janne

Journal or series: Journals of Gerontology Series A: Biological Sciences and Medical Sciences

ISSN: 1079-5006

eISSN: 1758-535X

Publication year: 1996

Volume: 52A

Issue number: 4

Pages range: 225-231

Publisher: Gerontological Society of America

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1093/gerona/52A.4.M225

Publication open access: Not open

Publication channel open access: 

Abstract

Background. -- Leg extension power can be determined as the product of the force and velocity of movement. Its association with maximal walking speed was studied in 131 80- and 85-year-old men and women. Methods. -- Leg extension power was measured with the help of a sledge ergometer in a sitting position using a facilitated “jump test.” The participant was attached by belts to a sliding chair on rails inclined at 12.6° to the floor. The feet were placed on the force plate attached perpendicularly to the rails, and the knee angle was 90° at the starting position. The participant was advised to extend his or her legs powerfully. The highest value of five to eight attempts was accepted as the result. The results were adjusted for body mass and expressed as watts-kilogram-1. Maximal walking speed was measured in the laboratory corridor over a distance of 10 m. Results. -- Men and 80-year-old subjects exhibited greater leg extension power and were faster walkers than women and 85-year-old persons. Leg extension power correlated positively with maximal walking speed in all groups: the correlation coefficients were .412 in the 80-year-old men (n = 41, p = .007), .619 in the 80-year-old women (n = 56, p < .001), .939 in the 85-year-old men (n = 8, p = .001), and .685 in the 85-year-old women (n = 23,p< .001). The regression lines for leg extension power and walking speed were coincident, indicating that the power requirements to attain a given walking speed were similar for both sexes. The minimum power threshold for those with a maximal walking speed of 1.30–1.49 m·s-1 was on the order of 4 W·Kg-1; a maximal walking speed of 1.50–1.99 m·s-1 required 7 W·kg-1; and for a speed over 2.00 m·s-1 the power threshold was 9.5 W·kg-1. Conclusions. -- Their lower average leg extension power may be one of the factors explaining the greater prevalence of mobility problems among women than men.

Keywords: older people; elderly; people living alone; physical functioning; legs; muscle strength; walking (motion); power (physics); gender differences

Free keywords: bone plates; knee region; knee joint; walkers; footleg; independent living; regression line; sitting position; mobility; watt; walking speed; ergometers

Contributing organizations

Ministry reporting: Yes

Preliminary JUFO rating: Not rated