Force-frequency relationship during fatiguing contractions of rat medial gastrocnemius muscle.

The force-frequency relationship presents the amount of force a muscle can produce as a function of the frequency of activation. During repetitive muscular contractions, fatigue and potentiation may both impact the resultant contractile response. However, both the apparent fatigue observed, and the potential for activity-dependent potentiation can be affected by the frequency of activation.

Cardiac rehabilitation in people with peripheral arterial disease: A higher risk population that benefits from completion.

Background: Peripheral arterial disease (PAD) is common in people referred for cardiac rehabilitation (CR). However, the associations between PAD diagnosis and CR attendance and mortality remain to be defined.

Methods: All patients referred to a 12-week exercise-based CR program were included.

Force-velocity relationship during isometric and isotonic fatiguing contractions.

Fatiguing contractions change the force-velocity relationship, but assessment of this relationship in fatigue has usually been obtained after isometric contractions. We studied fatigue caused by isometric or isotonic contractions, by assessment of the force-velocity relationship while the contractions maintaining fatigue were continued. This approach allowed determination of the force-velocity relationship during a steady condition of fatigue.

A proof-of-concept in vitro study to determine if EndoAnchors can reduce gutter size in chimney graft configurations.

Purpose: To investigate the feasibility of using endoanchor technology to reduce chimney graft-related gutter size in a juxtarenal aneurysm model.

Methods: In silicone juxtarenal aortic aneurysm models with two sizes of branch arteries and two sizes of aorta, single chimney graft (CG) configurations were constructed using 6-mm Atrium balloon-expandable stent-grafts in association with two sizes of Gore Excluder main grafts (23 and 28.5 mm).

Prediction of summation in incompletely fused tetanic contractions of rat muscle.

Summation is the accumulating contractile force resulting from sequential activations applied to a muscle without sufficient interval to permit complete relaxation. The purpose of this study was to evaluate summation in the rat medial gastrocnemius muscle, and to determine if the contractile responses during summation could be predicted from the relationship between force and activation pattern. In the first part of this study, the consistency of summation in the rat gastrocnemius muscle was assessed and prediction equations were derived.