Energy cost and muscular activity required for leg swing during walking.

Full Abstract

To investigate the metabolic cost and muscular actions required for the initiation and propagation of leg swing, we applied a novel combination of external forces to subjects walking on a treadmill. We applied a forward pulling force at each foot to assist leg swing, a constant forward pulling force at the waist to provide center of mass propulsion, and a combination of these foot and waist forces to evaluate leg swing. When the metabolic cost and muscle actions were at a minimum, the condition was considered optimal. We reasoned that the difference in energy consumption between the optimal combined waist and foot force trial and the optimal waist force-only trial would reflect the metabolic cost of initiating and propagating leg swing during normal walking. We also reasoned that a lower muscle activity with these assisting forces would indicate which muscles are normally responsible for initiating and propagating leg swing. With a propulsive force at the waist of 10% body weight (BW), the net metabolic cost of walking decreased to 58% of normal walking. With the optimal combination, a propulsive force at the waist of 10% BW plus a pulling force at the feet of 3% BW the net metabolic cost of walking further decreased to 48% of normal walking. With the same combination, the muscle activity of the iliopsoas and rectus femoris muscles during the swing phase was 27 and 60% lower, respectively, but the activity of the medial gastrocnemius and soleus before swing did not change. Thus our data indicate that approximately 10% of the net metabolic cost of walking is required to initiate and propagate leg swing. Additionally, the hip flexor muscles contribute to the initiation and propagation leg swing.

Author information

Author/s: Gottschall, Jinger S (JS); Kram, Rodger (R);

Affiliation: Department of Integrative Physiology, University of Colorado, Boulder, USA. jgottsc(-atsign-)emory.edu

Grants: AR-44688 (Agency:NIAMS NIH HHS)

Journal and publication information

Publication Type: Clinical Trial; Journal Article; Research Support, N.I.H., Extramural; Research Support, U.S. Gov't, P.H.S.

Journal: Journal of applied physiology (Bethesda, Md. : 1985) (J Appl Physiol), published in United States. (Language: eng)

Reference: 2005-Jul; vol 99 (issue 1) : pp 23-30

Dates: Created 2005/07/22; Completed 2005/09/19; Revised 2008/11/21;

PMID: 16036902, status: MEDLINE (last retrieval date: 2/18/2009, IMS Date: )

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article
(including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.