BACKGROUND Based on previously reported changes in muscle metabolism that could increase susceptibility to fatigue, we speculated that patients with chronic obstructive pulmonary disease (COPD) have reduced quadriceps endurance and that this will be correlated with the proportion of type I muscle fibres and with the activity of oxidative enzymes. METHODS The endurance of the quadriceps was ev...

Background: Based on previously reported changes in muscle metabolism that could increase susceptibility to fatigue, we speculated that patients with chronic obstructive pulmonary disease (COPD) have reduced quadriceps endurance and that this will be correlated with the proportion of type I muscle fibres and with the activity of oxidative enzymes. Methods: The endurance of the quadriceps was ev...

In sarcoidosis, pulmonary and general symptoms often do not correlate with radiographic stage and routinely performed lung function tests. Asymptomatic muscle involvement in sarcoidosis is common, but little is known about respiratory muscle involvement. The aim of this study was to investigate any relationships between persistent complaints and/or quality of life and respiratory muscle strengt...

The purpose of this cross-sectional study was to examine mean values of isometric torso muscle profiles of four spinal postures (good posture, thoracic kyphosis, lumbar lordosis and scoliosis) among 743 children from the ages of 7 to 14 years old. It was hypothesized that having good posture, thoracic hyper-kyphosis, lumbar hyper-lordosis and scoliosis is linked to different isometric torso mus...

OBJECTIVE To determine if there is an association between supine leg-length alignment (LLA) asymmetry and the endurance of the erector spinae (ES) and quadratus lumborum (QL) muscles. METHODS Forty-seven subjects (21 women; average age, 36 years old) were tested for ES endurance using the Biering-Sorensen (B-S) test, and 69 (31 women; average age, 34.5 years) were tested for QL endurance. Sub...

BACKGROUND Mitochondrial dysfunction may represent a pathogenic factor in Huntington disease (HD). Physical exercise leads to enhanced mitochondrial function in healthy participants. However, data on effects of physical exercise on HD skeletal muscle remains scarce. We aimed at investigating adaptations of the skeletal muscle mitochondria to endurance training in HD patients. METHODS Thirteen...

A quantitative method of muscle activity prediction is presented which uses a criterion of maximum endurance of musculoskeletal function and is based on the inversely nonlinear relationship of muscle force and contraction endurance. The results obtained through the use of this method agree more closely with known patterns of muscle activity, as revealed by electromyography, than do those obtain...