| Balance responses to lateral perturbations in human treadmill walking. | |
| | |
MedLine Citation:
|
PMID: 20639427 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
During walking on a treadmill 10 human subjects (mean age 20 years) were perturbed by 100 ms pushes or pulls to the left or the right, of various magnitudes and in various phases of the gait cycle. Balance was maintained by (1) a stepping strategy (synergy), in which the foot at the next step is positioned a fixed distance outward of the 'extrapolated centre of mass', and (2) a lateral ankle strategy, which comprises a medial or lateral movement of the centre of pressure under the foot sole. The extrapolated centre of mass is defined as the centre of mass position plus the centre of mass velocity multiplied by a parameter related to the subject's leg length. The ankle strategy is the fastest, with a mechanical delay of about 200 ms (20% of a stride), but it can displace the centre of pressure no more than 2 cm. The stepping strategy needs at least 300 ms (30% of a stride) before foot placement, but has a range of 20 cm. When reaction time is sufficient, the magnitude of the total response is in good agreement with our hypothesis: mean centre of pressure (foot) position is a constant distance outward of the extrapolated centre of mass. If the reaction time falls short, a further correction is applied in the next step. In the healthy subjects studied here, no further corrections were necessary, so balance was recovered within two steps (one stride). |
| | |
Authors:
|
A L Hof; S M Vermerris; W A Gjaltema |
Related Documents
:
|
9422457 - Piezo-dynamometric platform for a more complete analysis of foot-to-floor interaction. 18463297 - Effect of graded bicycle seat pressure on perineal compression: a magnetic resonance im... 17950217 - Is complete release of all volar carpal canal structures necessary for complete decompr... 11810617 - The effect of sectioning the dorsal radiocarpal ligament and insertion of a pressure se... 17403377 - Variability in response to antihypertensive drugs. 3591987 - Role for the median preoptic nucleus in centrally evoked pressor responses. |
Publication Detail:
|
Type: Clinical Trial; Journal Article |
Journal Detail:
|
Title: The Journal of experimental biology Volume: 213 ISSN: 1477-9145 ISO Abbreviation: J. Exp. Biol. Publication Date: 2010 Aug |
Date Detail:
|
Created Date: 2010-07-19 Completed Date: 2010-10-19 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0243705 Medline TA: J Exp Biol Country: England |
Other Details:
|
Languages: eng Pagination: 2655-64 Citation Subset: IM |
Affiliation:
|
Centre for Human Movement Sciences, University of Groningen, PO Box 196, Groningen, 9700 AD, The Netherlands. a.l.hof@med.umcg.nl |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Ankle
/
physiology Biomechanics Body Weight / physiology Exercise Test* Female Humans Male Postural Balance / physiology* Pressure Time Factors Walking / physiology* Young Adult |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Serotonin and its metabolism in basal deuterostomes: insights from Strongylocentrotus purpuratus and...
Next Document: Harbor seal vibrissa morphology suppresses vortex-induced vibrations.