The peculiar attributes of muscles that are stretched when active have been noted for nearly a century.Understandably,the focus of muscle physiology has been primarily on shortening and isometric contractions,as eloqu...The peculiar attributes of muscles that are stretched when active have been noted for nearly a century.Understandably,the focus of muscle physiology has been primarily on shortening and isometric contractions,as eloquently revealed by A.V.Hill and subsequently by his students.When the sliding filament theory was introduced by A.F.Huxley and H.E.Huxley,it was a relatively simple task to link Hill's mechanical observations to the actions of the cross bridges during these shortening and isometric contractions.In contrast,lengthening or eccentric contractions have remained somewhat enigmatic.Dismissed as necessarily causing muscle damage,eccentric contractions have been much more difficult to fit into the cross-bridge theory.The relatively recent discovery of the giant elastic sarcomeric filament titin has thrust a previously missing element into any discussion of muscle function,in particular during active stretch.Indeed,the unexpected contribution of giant elastic proteins to muscle contractile function is highlighted by recent discoveries that twitchin-actin interactions are responsible for the"catch"property of invertebrate muscle.In this review,we examine several current theories that have been proposed to account for the properties of muscle during eccentric contraction.We ask how well each of these explains existing data and how an elastic filament can be incorporated into the sliding filament model.Finally,we review the increasing body of evidence for the benefits of including eccentric contractions into a program of muscle rehabilitation and strengthening.展开更多
Zhejiang Hengxin Power Corp inaugurated startup of the first phase of its biomassbasedheat and power co-production project in Longyou of Zhejiang province on April14th,connecting the electricity to power grid.This is ...Zhejiang Hengxin Power Corp inaugurated startup of the first phase of its biomassbasedheat and power co-production project in Longyou of Zhejiang province on April14th,connecting the electricity to power grid.This is the first biomass heat and power co-production project that uses展开更多
基金supported by Kiisa Nishikawa: the National Science Foundation (IOS-0732949, IOS-1025806, and IOS1456868 IIP-1237878 and IIP-1521231)the W.M. Keck Foundation+5 种基金the Technology Research Initiative Fund of Northern Arizona UniversityPaul LaStayo:National Institutes of Health (ROIAG031255R21CA114523R21AG18701(with Stan Lindstedt))the Foundation for Physical Therapythe University of Utah Research Foundation
文摘The peculiar attributes of muscles that are stretched when active have been noted for nearly a century.Understandably,the focus of muscle physiology has been primarily on shortening and isometric contractions,as eloquently revealed by A.V.Hill and subsequently by his students.When the sliding filament theory was introduced by A.F.Huxley and H.E.Huxley,it was a relatively simple task to link Hill's mechanical observations to the actions of the cross bridges during these shortening and isometric contractions.In contrast,lengthening or eccentric contractions have remained somewhat enigmatic.Dismissed as necessarily causing muscle damage,eccentric contractions have been much more difficult to fit into the cross-bridge theory.The relatively recent discovery of the giant elastic sarcomeric filament titin has thrust a previously missing element into any discussion of muscle function,in particular during active stretch.Indeed,the unexpected contribution of giant elastic proteins to muscle contractile function is highlighted by recent discoveries that twitchin-actin interactions are responsible for the"catch"property of invertebrate muscle.In this review,we examine several current theories that have been proposed to account for the properties of muscle during eccentric contraction.We ask how well each of these explains existing data and how an elastic filament can be incorporated into the sliding filament model.Finally,we review the increasing body of evidence for the benefits of including eccentric contractions into a program of muscle rehabilitation and strengthening.
文摘Zhejiang Hengxin Power Corp inaugurated startup of the first phase of its biomassbasedheat and power co-production project in Longyou of Zhejiang province on April14th,connecting the electricity to power grid.This is the first biomass heat and power co-production project that uses
