Control and function of arm swing in human walking and running

Herman Pontzer, John H. Holloway, David A Raichlen, Daniel E. Lieberman

Research output: Contribution to journalArticle

110 Citations (Scopus)

Abstract

We investigated the control and function of arm swing in human walking and running to test the hypothesis that the arms act as passive mass dampers powered by movement of the lower body, rather than being actively driven by the shoulder muscles. We measured locomotor cost, deltoid muscle activity and kinematics in 10 healthy adult subjects while walking and running on a treadmill in three experimental conditions: control; no arms (arms folded across the chest); and arm weights (weights worn at the elbow). Decreasing and increasing the moment of inertia of the upper body in no arms and arm weights conditions, respectively, had corresponding effects on head yaw and on the phase differences between shoulder and pelvis rotation, consistent with the view of arms as mass dampers. Angular acceleration of the shoulders and arm increased with torsion of the trunk and shoulder, respectively, but angular acceleration of the shoulders was not inversely related to angular acceleration of the pelvis or arm. Restricting arm swing in no arms trials had no effect on locomotor cost. Anterior and posterior portions of the deltoid contracted simultaneously rather than firing alternately to drive the arm. These results support a passive arm swing hypothesis for upper body movement during human walking and running, in which the trunk and shoulders act primarily as elastic linkages between the pelvis, shoulder girdle and arms, the arms act as passive mass dampers which reduce torso and head rotation, and upper body movement is primarily powered by lower body movement.

Original languageEnglish (US)
Pages (from-to)523-534
Number of pages12
JournalJournal of Experimental Biology
Volume212
Issue number4
DOIs
StatePublished - Feb 15 2009

Fingerprint

walking
shoulders
Running
Walking
Arm
pelvis
muscle
torsion
inertia
cost
torso
kinematics
Pelvis
muscles
elbows
exercise equipment
chest
Weights and Measures
Head
Deltoid Muscle

Keywords

  • Arm swing
  • Passive dynamics
  • Running
  • Tuned mass dampers
  • Walking

ASJC Scopus subject areas

  • Animal Science and Zoology
  • Ecology, Evolution, Behavior and Systematics
  • Molecular Biology
  • Physiology
  • Insect Science
  • Aquatic Science

Cite this

Control and function of arm swing in human walking and running. / Pontzer, Herman; Holloway, John H.; Raichlen, David A; Lieberman, Daniel E.

In: Journal of Experimental Biology, Vol. 212, No. 4, 15.02.2009, p. 523-534.

Research output: Contribution to journalArticle

Pontzer, Herman ; Holloway, John H. ; Raichlen, David A ; Lieberman, Daniel E. / Control and function of arm swing in human walking and running. In: Journal of Experimental Biology. 2009 ; Vol. 212, No. 4. pp. 523-534.
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