Search results for "force"

The influence of ageing on the force-velocity-power characteristics of human elbow flexor muscles.

2003

Abstract The purpose of this study was to quantify the effects of ageing on the maximal power ( P max ) of the elbow flexor muscles and to determine the impact of velocity on the loss of power in older people. Sixteen elderly subjects (7 men and 9 women, age range 61–78 years) and 17 young subjects (11 men and 6 women, age range 18–27 years) participated in this study. Maximal elbow flexions were performed against increasing inertia. The maximal force ( F max ), maximal shortening velocity ( V max ), P max , dynamic constants ( a , b and a / F max ), optimal force ( F opt ), optimal velocity ( V opt ) and V opt / V max were determined from Hill's equation. Myoelectrical activity (EMG) of th…

Muscle activation during cycling at different cadences: Effect of maximal strength capacity

2007

International audience; The purpose of this study was to examine the influence of maximal strength capacity on muscle activation, during cycling, at three selected cadences: a low cadence (50 rpm), a high cadence (110 rpm) and the freely chosen cadence (FCC). Two groups of trained cyclists were selected on the basis of the different maximal isokinetic voluntary contraction values (MVCi) of their lower extremity muscles as follow: Fmin (lower MVCi group) and Fmax (higher MVCi group). All subjects performed three 4-min cycling exercises at a power output corresponding to 80 % of the ventilatory threshold under the three cadences. Neuromuscular activity of vastus lateralis (VL), rectus femoris…

Acute stress impairs reward positivity effect in probabilistic learning

2019

Decision making based on feedback learning requires a series of cognitive processes, including estimating the probability of particular outcomes and modulating expectations between expected versus actual outcomes. It has been suggested that stress affects decision making and subsequent processing of feedback valence and magnitude. However, less is known about the effect of acute stress on reward expectancy. In the current study, participants performed a probabilistic learning task, in which they learned an association between response and feedback within different reward expectancy trials (30% and 70%) under the conditions of stress (threat of shock) and safety (no shock). We recorded event…

Non-classic cystic fibrosis associated with D1152HCFTR mutation

2010

Burgel P-R, Fajac I, Hubert D, Grenet D, Stremler N, Roussey M, Siret D, Languepin J, Mely L, Fanton A, Labbe A, Domblides P, Vic P, Dagorne M, Reynaud-Gaubert M, Counil F, Varaigne F, Bienvenu T, Bellis G, Dusser D. Non-classic cystic fibrosis associated with D1152H CFTR mutation. Background: Limited knowledge exists on phenotypes associated with the D1152H cystic fibrosis transmembrane conductance regulator (CFTR) mutation. Methods: Subjects with a D1152H allele in trans with another CFTR mutation were identified using the French Cystic Fibrosis Registry. Phenotypic characteristics were compared with those of pancreatic insufficient (PI) and pancreatic sufficient (PS) cystic fibrosis (CF)…

Effects of fatigue and recovery on electromyographic and isometric force- and relaxation-time characteristics of human skeletal muscle

1986

Effects of fatigue produced by a maintained 60% isometric loading on electromyographic and isometric force-time and relaxation-time characteristics of human skeletal muscle were studied in 21 males accustomed to strength training. Fatigue loading resulted in a slight but not significant change in the maximal integrated EMG of a maximal isometric contraction, and a large decrease (20.4 +/- 6.3%, p less than 0.001) in maximal force. Fatigue loading increased (p less than 0.05-0.01) neural activation of the muscles during rapidly produced submaximal isometric forces, but had a considerable adverse effect (p less than 0.001) on the corresponding force-time characteristics. Correlations between …

Smoking in COPD Patients: A New Clinical Phenotype?

2017

Reperfusion therapy for ST elevation acute myocardial infarction 2010/2011:current status in 37 ESC countries

2014

Item does not contain fulltext AIMS: Primary percutaneous coronary intervention (PPCI) is the preferred reperfusion therapy in ST-elevation myocardial infarction (STEMI). We conducted this study to evaluate the contemporary status on the use and type of reperfusion therapy in patients admitted with STEMI in the European Society of Cardiology (ESC) member countries. METHODS AND RESULTS: A cross-sectional descriptive study based on aggregated country-level data on the use of reperfusion therapy in patients admitted with STEMI during 2010 or 2011. Thirty-seven ESC countries were able to provide data from existing national or regional registries. In countries where no such registries exist, dat…

Differences of airway dimensions between patients with and without bronchiolitis obliterans syndrome after lung transplantation-Computer-assisted qua…

2016

Abstract Background The aim of our retrospective study was to determine whether a dedicated software for assessment of airway morphology can detect differences in airway dimensions between patients with and without bronchiolitis obliterans syndrome (BOS), regarded as the clinical correlate of chronic lung allograft rejection. Methods 12 patients with and 14 patients without diagnosis of BOS were enrolled in the study. Evaluation of bronchial wall area percentage (WA%) and bronchial wall thickness (WT) in all follow-up CT scans was performed using a semiautomatic airway assessment tool. We assessed temporal changes (ΔWA%, ΔWT) and compared these morphological parameters with forced expirator…

Differences in pitch between tones affect behaviour even when incorrectly identified in direction.

2001

The ability to detect differences between simultaneously presented contra- and ipsilesional stimuli but not to identify the former on neurological patients with the symptom termed 'extinction' has given rise to the hypothesis that extinguished stimuli have impaired access to attentive processing but are detected pre-attentively. Such a dissociation found in normal participants with experimentally degraded sensory information, and its absence in equivalent tasks in terms of the amount of information required has, however, led to an alternative hypothesis that the lesser amount of information required to perform same/different judgements is sufficient to explain this dissociation. In the pres…

Measurement of inflammatory mediators of eosinophils and lymphocytes in blood in acute asthma: serum levels of ECP influence the bronchodilator respo…

2002

The aim of this study was to assess the relevance of immunoinflammatory markers on the response to short acting β<sub>2</sub>-agonist in acute asthma exacerbation. Thus, we measured serum eosinophil cationic protein (ECP) levels and sIL-2R at acute exacerbation in 52 adult patients with atopic asthma, and assessed forced expiratory volume in 1 s (FEV<sub>1</sub>) before and after the administration of aerosolized salbutamol. After a cumulative dose of salbutamol causing a 10% improvement in FEV<sub>1</sub> from baseline [CD10, i.e. cumulative doses of salbutamol (800 µg) causing an improvement in FEV<sub>1</sub> from baseline to 10%] the patie…