Dataset Information

Muscle size explains low passive skeletal muscle force in heart failure patients.

ABSTRACT:

Background

Alterations in skeletal muscle function and architecture have been linked to the compromised exercise capacity characterizing chronic heart failure (CHF). However, how passive skeletal muscle force is affected in CHF is not clear. Understanding passive force characteristics in CHF can help further elucidate the extent to which altered contractile properties and/or architecture might affect muscle and locomotor function. Therefore, the aim of this study was to investigate passive force in a single muscle for which non-invasive measures of muscle size and estimates of fiber force are possible, the soleus (SOL), both in CHF patients and age- and physical activity-matched control participants.

Methods

Passive SOL muscle force and size were obtained by means of a novel approach combining experimental data (dynamometry, electromyography, ultrasound imaging) with a musculoskeletal model.

Results

We found reduced passive SOL forces (?30%) (at the same relative levels of muscle stretch) in CHF vs. healthy individuals. This difference was eliminated when force was normalized by physiological cross sectional area, indicating that reduced force output may be most strongly associated with muscle size. Nevertheless, passive force was significantly higher in CHF at a given absolute muscle length (non length-normalized) and likely explained by the shorter muscle slack lengths and optimal muscle lengths measured in CHF compared to the control participants. This later factor may lead to altered performance of the SOL in functional tasks such gait.

Discussion

These findings suggest introducing exercise rehabilitation targeting muscle hypertrophy and, specifically for the calf muscles, exercise that promotes muscle lengthening.

SUBMITTER: Panizzolo FA

PROVIDER: S-EPMC5028761 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Publications

Muscle size explains low passive skeletal muscle force in heart failure patients.

Panizzolo Fausto Antonio FA Maiorana Andrew J AJ Naylor Louise H LH Dembo Lawrence G LG Lloyd David G DG Green Daniel J DJ Rubenson Jonas J

PeerJ 20160915

<h4>Background</h4>Alterations in skeletal muscle function and architecture have been linked to the compromised exercise capacity characterizing chronic heart failure (CHF). However, how passive skeletal muscle force is affected in CHF is not clear. Understanding passive force characteristics in CHF can help further elucidate the extent to which altered contractile properties and/or architecture might affect muscle and locomotor function. Therefore, the aim of this study was to investigate passi ...[more]

PMID: 27672504

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Dataset Information

Muscle size explains low passive skeletal muscle force in heart failure patients.

Background

Methods

Results

Discussion

Publications

Muscle size explains low passive skeletal muscle force in heart failure patients.

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