Show simple item record

dc.contributor.authorSmith, N.
dc.contributor.authorBarclay, Chris
dc.contributor.authorLoiselle, D.
dc.date.accessioned2018-10-29T01:00:58Z
dc.date.available2018-10-29T01:00:58Z
dc.date.issued2005
dc.identifier.issn0079-6107en_US
dc.identifier.urihttp://hdl.handle.net/10072/83060
dc.description.abstractWhen a muscle contracts and shortens against a load, it performs work. The performance of work is fuelled by the expenditure of metabolic energy, more properly quantified as enthalpy (i.e., heat plus work). The ratio of work performed to enthalpy produced provides one measure of efficiency. However, if the primary interest is in the efficiency of the actomyosin cross-bridges, then the metabolic overheads associated with basal metabolism and excitation-contraction coupling, together with those of subsequent metabolic recovery process, must be subtracted from the total heat and work observed. By comparing the cross-bridge work component of the remainder to the Gibbs free energy of hydrolysis of ATP, a measure of thermodynamic efficiency is achieved. We describe and quantify this partitioning process, providing estimates of the efficiencies of selected steps, while discussing the errors that can arise in the process of quantification. The dependence of efficiency on animal species, fibre-type, temperature, and contractile velocity is considered. The effect of contractile velocity on energetics is further examined using a two-state, Huxley-style, mathematical model of cross-bridge cycling that incorporates filament compliance. Simulations suggest only a modest effect of filament compliance on peak efficiency, but progressively larger gains (vis-a-vis the rigid filament case) as contractile velocity approaches Vmax. This effect is attributed primarily to a reduction in the component of energy loss arising from detachment of cross-bridge heads at non-zero strain.en_US
dc.languageEnglishen_US
dc.publisherElsevieren_US
dc.publisher.placeAmsterdamen_US
dc.publisher.uri10.1016/j.pbiomolbio.2003.11.014en_US
dc.relation.ispartofpagefrom1en_US
dc.relation.ispartofpageto58en_US
dc.relation.ispartofissue1en_US
dc.relation.ispartofjournalProgress in Biophysics and Molecular Biologyen_US
dc.relation.ispartofvolume88en_US
dc.subject.fieldofresearchcode270601en_US
dc.subject.fieldofresearchcode270602en_US
dc.titleThe efficiency of muscle contractionen_US
dc.typeJournal articleen_US
dc.type.descriptionC2 - Non HERDC Eligibleen_US
dc.type.codeC - Journal Articlesen_US
gro.hasfulltextNo Full Text
gro.griffith.authorBarclay, Chris


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

  • Journal articles
    Contains articles published by Griffith authors in scholarly journals.

Show simple item record