Search results for "Fatigue"
showing 10 items of 651 documents
Effect of xanthine oxidase-generated extracellular superoxide on skeletal muscle force generation
2009
Skeletal muscle contractions increase superoxide anion in skeletal muscle extracellular space. We tested the hypotheses that 1) after an isometric contraction protocol, xanthine oxidase (XO) activity is a source of superoxide anion in the extracellular space of skeletal muscle and 2) the increase in XO-derived extracellular superoxide anion during contractions affects skeletal muscle contractile function. Superoxide anion was monitored in the extracellular space of mouse gastrocnemius muscles by following the reduction of cytochrome c in muscle microdialysates. A 15-min protocol of nondamaging isometric contractions increased the reduction of cytochrome c in microdialysates, indicating an …
Effects of Constant and Doublet Frequency Electrical Stimulation Patterns on Force Production of Knee Extensor Muscles
2016
International audience; This study compared knee extensors' neuromuscular fatigue in response to two 30-minute stimulation patterns: constant frequency train (CFT) and doublet frequency train (DFT). Fifteen men underwent two separate sessions corresponding to each pattern. Measurements included torque evoked by each contraction and maximal voluntary contractions (MVC) measured before and immediately after the stimulation sessions. In addition, activation level and torque evoked during doublets (Pd) and tetanic contractions at 80-Hz (P80) and 20-Hz (P20) were determined in six subjects. Results indicated greater mean torque during the DFT stimulation session as compared with CFT. But, no dif…
Training-Induced Acute Neuromuscular Responses to Military Specific Test during a Six-Month Military Operation
2021
Limited data are available regarding strength and endurance training adaptations to occupational physical performance during deployment. This study assessed acute training-induced changes in neuromuscular (electromyography
Regular physical exercise before entering military service may protect young adult men from fatigue fractures
2019
Background Bone stress fractures are overuse injuries commonly encountered in sports and military medicine. Some fatigue fractures lead to morbidity and loss of active, physically-demanding training days. We evaluated the incidence, anatomical location, risk factors, and preventive measures for fatigue fractures in young Finnish male conscripts. Methods Five cohorts of 1000 men performing military service, classified according to birth year (1969, 1974, 1979, 1984, 1989), were analysed. Each conscript was followed for his full military service period (180 days for conscripts with rank and file duties, 270 days for those with special training, 362 days for officers and highly trained conscri…
Socio-demographic, health-related, and individual correlates of diagnostic self-testing by lay people: Results from a representative survey in Germany
2017
Introduction A broad range of self-tests (testing for e.g. HIV, cancer, hepatitis B/C) have become available and can be conducted by lay consumers without the help of a health professional. The aims of this study were to (a) investigate the prevalence of self-testing, (b) identify the most frequently used self-tests, and (c) explore the associations between socio-demographic, health-related and individual factors with self-testing. Methods A face-to-face plus paper-pencil cross-sectional survey was conducted. The sample consisted of 2.527 respondents who were representative of the German population in terms of the age, sex, and residence. Basic descriptive statistics and univariate logistic…
The longer the better: Sleep–wake patterns during preparation of the World Rowing Junior Championships
2016
Recovery is essential for high athletic performance, and therefore especially sleep has been identified as a crucial source for physical and psychological well-being. However, due to early-morning trainings, which are general practice in many sports, athletes are likely to experience sleep restrictions. Therefore, this study investigated the sleep-wake patterns of 55 junior national rowers (17.7 ± 0.6 years) via sleep logs and actigraphy during a four-week training camp. Recovery and stress ratings were obtained every morning with the Short Recovery and Stress Scale on a 7-point Likert-type scale ranging from 0 (does not apply at all) to 6 (fully applies). The first training session was sch…
Kayaking performance is altered in mentally fatigued young elite athletes
2019
Background The present study aimed to assess the impact of 60 min of a cognitive demanding task inducing mental fatigue (Stroop) on kayaking performance in young elite athletes. The second objective was to elucidate the effect of mental fatigue on performance in a population of young under-17 elite athletes of national. Methods Thirteen under-17 elite kayakers completed 60 min of an incongruent Stroop color-word test, or the equivalent time in a control condition in a cross-over study design. Afterwards, participants completed a 2000 m kayaking time trial in which power output, stroke rate and time at the end of 400, 800, 1200, 1600 and 2000 m were recorded. Physiological and perceptual mea…
‘Sometimes it feels as if the world goes on without me’: adolescents' experiences of living with chronic fatigue syndrome
2013
Aims and objectives To explore the experience of being an adolescent with chronic fatigue syndrome. Background Despite ample research, chronic fatigue syndrome is still poorly understood, and there are still controversies related to the illness. Adolescents with chronic fatigue syndrome are often unable to attend school and lose social relations with friends. The challenges they face will affect their quality of life. Design A qualitative, phenomenological hermeneutical design. Method Six boys and twelve girls, aged 12–18, were interviewed, emphasising their own experiences living with chronic fatigue syndrome. Analyses were performed using a phenomenological hermeneutical method. Results T…
Cognitive functioning in orthostatic hypotension due to pure autonomic failure.
2004
Psychophysiological science proposes close interactions between cognitive processes and autonomic responses, yet the consequences of autonomic failure on cognitive functioning have not been documented. This pilot study investigates, for the first time, the cognitive profile of 14 patients with Pure Autonomic Failure (PAF). Each patient was administered a comprehensive battery of neuropsychological tests and neuroimaging investigation. A number of patients (n = 6) presented with cognitive impairment. The two most frequent types of impairment were: deficits of speed and attention, and executive functioning. Impairments of free recall memory, intellectual functioning, nominal and calculation f…
The Impact of Fluid Loss and Carbohydrate Consumption during Exercise, on Young Cyclists’ Fatigue Perception in Relation to Training Load Level
2021
High-level young athletes need to face a wide spectrum of stressors on their journey to élite categories. The aims of the present study are (i) to evaluate session rate of perceived exertion (sRPE) at different training impulse (TRIMP) categories and the correlations between these two variables and, (ii) evaluate the correlations between sRPE, fluid loss, and carbohydrate consumption during exercise. Data on Edward’s TRIMP, sRPE, body mass loss pre- and post- exercise (∆), and carbohydrate consumption (CHO/h) during exercise have been acquired from eight male junior cyclists during a competitive season. One-way ANOVA and correlation analysis with linear regression have been performed on acq…