We investigated the extent of mechanical interaction between rat flexor carpi ulnaris (FCU) and palmaris longus (PL) muscles following transfer of FCU to the distal tendons of extensor carpi radialis brevis and longus (ECRB/L) muscles. Five weeks after recovery from surgery, isometric forces exerted at the distal tendons of FCU and PL were quantified at various FCU lengths. PL was kept at a con...

A common complication of reconstructive surgery is muscle contracture and consequent loss of joint motion. This particularly occurs in surgical lengthening procedures where the muscle adaptive capacity seems to limit the extent of possible lengthening. We used intraoperative laser diffraction to determine the skeletal muscle adaptation that occurred in a 16-year-old girl who had 4-cm femoral le...

OBJECTIVE To investigate whether muscle strength is selectively more affected at shorter lengths of thigh muscles as result of stroke and to determine whether this is associated with impaired neural activation at shorter muscle lengths. DESIGN Case-control study. SUBJECTS Fourteen patients with sub-acute stroke, and 12 able-bodied controls. METHODS In patients (bilaterally) and able-bodie...

A fundamental feature of vertebrate muscle is that maximal force can be generated only over a limited range of lengths. It has been proposed that locomotor muscles operate over this range of lengths in order to maximize force production during movement. However, locomotor behaviours like jumping may require muscles to shorten substantially in order to generate the mechanical work necessary to p...

Mathematical calculations of muscle forces often require an estimate of a given muscle’s capacity to generate force. A traditional way of expressing a muscle’s fora generating capacity is in terms of its ‘physiological cross-sectional area’ (degned by muscle volume or muscle mass divided by either gross musck length or muscle fiber length with or without accounting for pennation) (Brand et al.....

We studied changes in the relationship of isometric developed force to muscle length when extracellular calcium concentration was altered in isolated cat papillary muscles. In two series of experiments at temperatures of 30 degrees C and 32 degrees C, and rates of 12 and 30 beats/min, 21 muscles were exposed to calcium concentrations of 1.125, 2.25 and 4.5 mM. Muscle lengths were varied between...

in current research relationship between eicosapentaenoic acid (epa) and docosahexaenoic acid (dha) (% of total fatty acids) in edible tissue (muscle) of green tiger shrimp (penaeus semisulcatus) and lobster (thenus orientalis) collected from persian gulf, was investigated with some biological factors (total length, total weight and sex). results showed that in all two species, epa and dha perc...

• The sarcomere is the basic ultrastructural unit of contraction in striated muscle. Huxley and Hanson have shown that the alternating band patterns of the sarcomere in skeletal muscle derive from the longitudinal disposition of two sets of interdigitating contractile protein filaments. On the basis of these and other studies, the sliding filament hypothesis for muscle contraction was proposed....

Barnacle single muscle fibers were microinjected with the calcium-specific photoprotein aequorin. We have previously shown (Ridgway, E. B., and A. M. Gordon, 1984, Journal of General Physiology, 83:75-104) that when barnacle fibers are stimulated under voltage clamp and length control and allowed to shorten during the declining phase of the calcium transient, extra myoplasmic calcium is observe...

Skeletal muscles change length and develop force both passively and actively. Gearing allows muscle fiber length changes to be uncoupled from those of the whole muscle-tendon unit. During active contractions this process allows muscles to operate at mechanically favorable conditions for power or economical force production. Here we ask whether gearing is constant in passive muscle; determining ...