Purpose: Knee osteoarthritis (OA) is believed to be an important risk factor for falling. Total knee replacement (TKR) is a commonly used choice when other methods are not satisfactory. Proprioception impairment, risk of falling and balance disorder are within the main complications of this method. While multiple protocols have been suggested for TKR, efficacy of early isotonic ...

In order to meet the varying demands of flight, pectoralis muscle power output must be modulated. In birds with pectoralis muscles with a homogeneous fibre type composition, power output can be modulated at the level of the motor unit (via changes in muscle length trajectory and the pattern of activation), at the level of the muscle (via changes in the number of motor units recruited), and at t...

Achillea millefolium L. is cultivated in Iran and widely used in traditional medicine for gastrointestinal disorders. The aim of this study was to determine the effect of hydroalcoholic extract of A. millefolium on the contraction and relaxation of isolated ileum in rat. In this experimental study, aerial parts of A. millefolium were extracted by maceration in ethanol 70% for 72 h. Terminal por...

The aim of this human study was to investigate the effect of experimentally induced muscle pain on the modifications of motor unit discharge rate during sustained, constant-force contractions. Intramuscular and multichannel surface electromyographic (EMG) signals were collected from the right and left tibialis anterior muscle of 11 volunteers. The subjects performed two 4-min-long isometric con...

BACKGROUND The esophagus has a different response in relation to the characteristics of a swallowed bolus. Bolus viscosity and body position may affect esophageal contraction and transit. Objectives To investigate the effect of bolus viscosity and body position on esophageal contraction, transit and perception. METHODS Esophageal contraction, transit and perception of transit were evaluated i...

The standard isotonic regression of a vector in IRn is the solution to a least squares projection problem on the cone C of vectors with ‘increasing components’ in IRn. Generalized isotonic regression problems are isotonic optimization problems that seem to be quite different from isotonic regression problems, but in fact have the same solution. In problems of maximum smoothed likelihood estimat...

Twelve endurance athletes and six power athletes performed fatiguing isokinetic knee flexions/extensions. Isokinetic torque was recorded during the exercise. Isometric torque, cortisol and lactate responses, electromyographic (EMG) mean power frequency, average rectified value, and conduction velocity were analysed before and after the isokinetic exercise to determine correlations between elect...

The purpose of this study was to compare three different intervals for a between sets rest period during a common isokinetic knee extension strength-testing protocol of twenty older Brazilian men (66.30 ± 3.92 yrs). The volunteers underwent unilateral knee extension (Biodex System 3) testing to determine their individual isokinetic peak torque at 60, 90, and 120°s(-1). The contraction speeds an...

BACKGROUND Foot dorsiflexion plays an essential role in both controlling balance and human gait. Electromyography (EMG) and sonomyography (SMG) can provide information on several aspects of muscle function. The aim was to establish the relationship between the EMG and SMG variables during isotonic contractions of foot dorsiflexors. METHODS Twenty-seven healthy young adults performed the foot ...

Conventional bipolar EMG provides imprecise muscle activation estimates due to possibly heterogeneous activity within muscles and due to improper alignment of the electrodes with the muscle fibers. Principal component analysis (PCA), applied on multi-channel monopolar EMG yielded substantial improvements in muscle activation estimates in pennate muscles. We investigated the degree of heterogene...