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Results 201 - 250 of 1232
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Marino F E - - 2011
The study of human fatigue stretches back centuries and remains a significant part of medical and social discourse. In the exercise sciences fatigue is routinely related to the ability to produce muscle force or to the recovery from force decrements. However, the study of fatigue has by virtue of the ...
Paillard T - - 2010
Fatiguing exercise of the quadriceps femoris muscle degrades postural control in human subjects. The aim of this work was to compare the effects of the fatigue of the quadriceps femoris induced by voluntary muscular contraction (VC), and by electrical stimulation (ES) superimposed onto voluntary muscular contraction (VC+ES), on postural control ...
Zafeiridis Andreas - - 2010
This study examined fatigue profile during intermittent exercise in 10 men with mild to moderate mental retardation (MR) and 10 men without mental retardation (C). They performed 4 x 30s maximal knee extensions and flexions with 1-min rest on an isokinetic dynamometer. Peak torque of flexors (PTFL) and extensors (PTEX), ...
Piitulainen Harri - - 2010
High-density surface electromyography was used to examine whether gross sarcolemmal function is impaired in m. biceps brachii after intensive eccentric elbow flexor exercise, when measured at wide range of isometric contraction levels. Root mean square (RMS), mean power frequency (MNF) and mean muscle fibre conduction velocity (CV) were calculated before ...
Wen Guo - - 2009
Acetylcholinesterase is the enzyme that terminates neurotransmission by hydrolyzing the acetylcholine released by the motoneurons at the neuromuscular junctions. Although acetylcholinesterase has been studied for almost a century, the underlying relationship between exercise-induced fatigue and acetylcholinesterase activity at the synaptic cleft is not clear. The purpose of this study was ...
Camic Clayton L - - 2010
The purposes of this investigation were twofold: (1) to determine if the model used for estimating the physical working capacity at the fatigue threshold (PWC(FT)) from electromyographic (EMG) amplitude data could be applied to the frequency domain of the signal to derive a new fatigue threshold for cycle ergometry called ...
Hunter Angus M - - 2009
The aim of this study was to determine if inducing metabolic alkalosis would alter neuromuscular control after 50 min of standardized submaximal cycling. Eight trained male cyclists (mean age 32 years, s = 7; [Vdot]O(2max) 62 ml . kg(-1) x min(-1), s = 8) ingested capsules containing either CaCO(3) (placebo) ...
Hedayatpour Nosratollah - - 2009
: Eccentric contractions induce muscle fiber damage that is associated with a decreased capacity to generate voluntary force and increased fiber membrane permeability. Changes in fiber membrane permeability results in cell depolarization that is expected to have an effect on the action potential propagation velocity of the muscle fibers. : ...
Wood Lisa J - - 2009
To review evidence that muscle-derived interleukin-6 (IL-6) mediates some of the beneficial effects of exercise on cancer treatment-related fatigue (CTRF). Electronic nursing, psychology, and medicine databases. Fatigue is a common and often debilitating symptom associated with cancer treatment. Although the molecular mechanisms underlying CTRF have yet to be fully elucidated, ...
Nishijima Y - - 2010
This study aims at determining the applicability of a segment weight dynamic movement (SWDM) method as an alternative for normalizing gait EMGs in comparison with the conventional isometric maximal voluntary contraction (MVC) method. The SWDM method employs reference exercises, each being a dynamic, repetitive movement of a joint under the ...
Vianna Lauro C - - 2009
The purpose of the present study was to determine the relative importance of peripheral feedback from mechanically (mechanoreflex) and metabolically (metaboreflex) sensitive muscle afferents and central signals arising from higher centers (central command) to the exercise-induced increases in regional cerebral perfusion. To accomplish this, anterior cerebral artery (ACA) mean blood ...
Buss Tomasz - - 2010
PURPOSE: The study was focused on the influence of the kinesitherapy on fatigue and the quality of life in the terminal hospice cancer patients. PATIENTS AND METHODS: Forty-nine patients were included into the study and divided into experimental group A (with kinesitherapy) with 30 subjects and control group B (without ...
Ekkekakis Panteleimon - - 2009
Near-infrared spectroscopy (NIRS) presents an appealing option for investigating hemodynamic changes in the cerebral cortex during exercise. This review examines the physical basis of NIRS and the types of available instruments. Emphasis is placed on the physiological interpretation of NIRS signals. Theories from affective neuroscience and exercise psychobiology, including Davidson's ...
Moran Kieran A - - 2009
Although from an athletic performance perspective it may be beneficial to undertake drop jump training when fatigued (principle of "specificity" of training), such endurance fatigue may expose the body to a greater risk of injury if it causes an increase in peak impact accelerations. This study aimed to determine if ...
Morana Claire - - 2009
This study aimed to measure time course of postactivation potentiation during intermittent submaximal fatiguing isometric contractions in 2 groups of subjects with different physical training history. Fifteen men subjects (8 endurance-trained athletes [END] and 7 power-trained athletes [POW]) performed a 10-minute intermittent (5-second contraction, 5-second rest) knee extension exercise at ...
Light Alan R - - 2009
Chronic fatigue syndrome (CFS) is characterized by debilitating fatigue, often accompanied by widespread muscle pain that meets criteria for fibromyalgia syndrome (FMS). Symptoms become markedly worse after exercise. Previous studies implicated dysregulation of the sympathetic nervous system (SNS), and immune system (IS) in CFS and FMS. We recently demonstrated that ...
Karabulut Murat - - 2010
This study investigated neuromuscular fatigue following low-intensity resistance exercise with vascular restriction (VR) and without vascular restriction (control, CON). Fourteen males participated in two experimental trials (VR and CON) each separated by 48 h. Each participant performed two isometric maximum voluntary contractions (MVCs) before and after five sets of 20 ...
Rösler Kai M KM Department of Neurology, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland, - - 2009
The objective of this study was to analyze central motor output changes in relation to contraction force during motor fatigue. The triple stimulation technique (TST, Magistris et al. in Brain 121(Pt 3):437-450, 1998) was used to quantify a central conduction index (CCI = amplitude ratio of central conduction response and ...
Ahtiainen Juha P - - 2009
Acute neuromuscular responses to maximum versus forced repetition (FR) knee extension resistance exercises (4 sets of 12 repetitions [reps] with a 2-minute recovery between the sets) were examined in 4 male strength athletes (SAs) and 4 nonathletes. Maximum repetition (MR) sets were performed to voluntary exhaustion (12 repetition maximum [RM]), ...
Kremenic Ian J - - 2009
Central and peripheral mechanisms contribute to fatigue during exercise. Electrical and transcranial magnetic stimulation have been used to assess these fatigue mechanisms. Peripheral magnetic stimulation (PMS) of the femoral nerve is associated with very little subject discomfort and has been shown to elicit quadriceps contractions of >70% maximal voluntary contraction ...
Drinkwater Eric J - - 2009
Although plyometric training is widely used by sports coaches as a method of improving explosive power in athletes, many prescribe volumes in excess of the National Strength and Conditioning Association recommendations. The purpose of this study was to assess voluntary and evoked muscle characteristics to assess the neuromuscular impact of ...
Gruet M - - 2010
The aim of this study was to investigate the long term reliability of surface electromyography (sEMG) measurements in adults with cystic fibrosis (CF). Eighteen healthy subjects (CO) and sixteen adults with CF were tested on two occasions, six weeks apart. sEMG was recorded from the rectus femoris, vastus lateralis and ...
Herring Matthew P - - 2009
We examined the effect of acute moderate- to high-intensity resistance exercise on feelings of energy and fatigue in sedentary college women reporting a persistent above-average frequency of fatigue. Fourteen sedentary female volunteers reporting persistent fatigue completed three counterbalanced conditions [70% one-repetition maximum (1-RM), 15% 1-RM/placebo, and a no-exercise control]. In ...
Bartels Matthew N - - 2009
Fatigue is often the major presenting complaint in patients with cardiac or pulmonary disease. This review explores a number of the multiple possible causes of fatigue in this population of patients. The identification of fatigue and possible approaches to the treatment of fatigue in cardiopulmonary patients are presented. Finally, the ...
Gordon Brett - - 2009
INTRODUCTION: Chronic fatigue syndrome (CFS) is a condition of prolonged and disabling fatigue, which is accompanied by characteristic constitutional and neuropsychiatric symptoms. In children and adolescents, this condition occurring at a developmentally vulnerable time adds to the disability affecting self-concept, autonomy, body image, socialisation, sexuality and academic problems. This case ...
Seifert John - - 2009
Common indices of fatigue may not respond similarly between downhill skiing and other activities because of the influence of factors such as snow conditions, changing terrain, and skiing style. The purpose of this study was to investigate the relationship and predictors of common fatigue indices during downhill skiing. Ten healthy ...
Pan John C - - 2009
Today, fatigue still remains an under-reported symptom in rheumatologic diseases, infrequently addressed by patient and physician. Although not all of the causes of fatigue in rheumatologic diseases have been fully elucidated, recognizing the multifactorial components is essential in formulating targeted, effective treatment strategies. Deconstructing rheumatologic diseases into discrete symptoms such ...
Vuillerme Nicolas - - 2009
Although previous studies have investigated the effects of bilateral muscle fatigue on bipedal postural control, whether and how the central nervous system could adapt to unilateral muscle fatigue for controlling bipedal stance remains to be investigated. The purpose of the present experiment was designed to address this issue by assessing ...
Pereira G - - 2009
The aim of this study was to directly compare the causes of fatigue after a short- and a long-rest interval between consecutive stretch-shortening cycle exercises. Eleven healthy males jumped with different resting period lengths (short=6.1+/-1 s, long=8.6+/-0.9 s), performing countermovement jumps at 95% of their maximal jump height until they ...
Kwan Bethany M - - 2010
OBJECTIVES: To test whether affective response to an acute bout of exercise can predict regular voluntary exercise, and specifically whether a positive affective response helps translate intentions into behaviour. DESIGN: A prospective correlational design. METHODS: Participants (N=127) recruited from the community reported intentions to engage in voluntary exercise and frequency ...
Izquierdo M - - 2009
This study examined the effects of heavy resistance training on dynamic exercise-induced fatigue task (5 x 10RM leg-press) after two loading protocols with the same relative intensity (%) (5 x 10RM(Rel)) and the same absolute load (kg) (5 x 10RM(Abs)) as in pretraining in men (n=12). Maximal strength and muscle ...
Robinson M - - 2010
The aim of the current study was to investigate the levels of interleukin-6 (IL-6), its soluble receptors (sIL-6R and sgp130) and F(2)-isoprostanes, at rest and during exercise, in patients with chronic fatigue syndrome (CFS). Six male CFS patients and six healthy controls performed an incremental exercise test to exhaustion and ...
Pereira Marta Inez R - - 2009
Cerebral contra-lateral frontal lobe and the dominant vastus lateralis muscle oxygenation (Cox, Mox) and blood volume (Cbv, Mbv) were recorded simultaneously using near infrared spectroscopy (NIRS) in 12 healthy volunteers (37.4 +/- 9.9 years; 72.3 +/- 16.1 kg; 171.0 +/- 9.6 cm) during 2 min resting baseline, an isometric knee ...
Baptista R R - - 2009
Skeletal muscle force production following repetitive contractions is preferentially reduced when muscle is evaluated with low-frequency stimulation. This selective impairment in force generation is called low-frequency fatigue (LFF) and could be dependent on the contraction type. The purpose of this study was to compare LFF after concentric and eccentric maximal ...
Gardner A Scott - - 2009
Previous investigators have quantified fatigue during short maximal cycling trials ( approximately 30 s) by calculating a fatigue index. Other investigators have reported a curvilinear power-pedaling rate relationship during short fatigue-free maximal cycling trials (<6 s). During maximal trials, pedaling rates may change with fatigue. Quantification of fatigue using fatigue ...
Lin Dingding - - 2009
The purposes of this study were to investigate the effects of fatigue location and age on changes in postural control induced by localized muscle fatigue, as well as the patterns of recovery post-fatigue. Groups of 16 younger (18-25 years) and 16 older (55-65 years) participants performed submaximal isotonic fatiguing exercises ...
White A T - - 2009
BACKGROUND: Multiple sclerosis (MS) patients experience fatigue as a chronic symptom that decreases quality of life. Commonly, fatigue in MS patients is manifested as decreased motor function during or after physical activity and is associated with changes in brain metabolism. OBJECTIVE: To determine brain activation patterns in MS patients and ...
Moraes Antonio C - - 2009
OBJECTIVE: The aim of this study was to describe by means of surface electromyography the activation of the rectus abdominis, obliquus externus and rectus femoris muscles during the "crunch" abdominal exercise performed with loads. METHODS: Thirteen subjects performed crunch exercises with loads representing 80, 60, 40 and 20% of the ...
Dritsa Maria - - 2009
OBJECTIVES: (1) To explore moderators of the effects of home-based exercise on reductions in physical and mental fatigue scores in postpartum depressed women and (2) to explore mediators of the intervention on changes in physical fatigue. METHOD: Eighty-eight women in the postpartum period (4-38 weeks) obtaining a score >or=10 on ...
Shibuya Kenichi - - 2009
Previous studies have investigated the relationship between prefrontal cortex activation and perceived exertion during prolonged exercise. However, the effect of perceived exertion on prefrontal cortex activity is confounded by exercise intensity. Therefore, the changes in prefrontal cortex activity in response to perceived exertion remain unclear. The purpose of the present ...
Windsor P M - - 2009
AIMS: An observational cohort study in patients undergoing treatment at a single cancer centre to evaluate the usefulness of providing written information on exercise and fatigue to patients at the start of their treatment, to assess whether patients exercised during treatment and their level of fatigue before and after treatment. ...
Girard Olivier - - 2010
The alteration in neuromuscular function of knee extensor muscles was characterised after a squash match in 10 trained players. Maximal voluntary contraction (MVC) and surface EMG activity of vastus lateralis (VL) and vastus medialis (VM) muscles were measured before and immediately after a 1-h squash match. M-wave and twitch contractile ...
Gauche Elodie - - 2009
PURPOSE: This study investigated neuromuscular fatigue following high versus low-intensity eccentric exercise corresponding to the same amount of work. METHODS: Ten volunteers performed two eccentric exercises of the elbow flexors: a high-intensity versus a low-intensity exercise. Maximal voluntary contraction torque and surface electromyography of the biceps brachii muscle were recorded ...
Oncu Jülide - - 2009
OBJECTIVE: To investigate and compare the impact of hospital and home exercise programmes on aerobic capacity, fatigue, and quality of life in patients with post-polio syndrome. DESIGN: A prospective, randomized controlled trial. SETTING: Department of Physical Medicine and Rehabilitation, University Hospital. SUBJECTS: Thirty-two patients were divided into two groups for ...
Yu Xiaoming - - 2009
Critical swimming speed (U(crit)) and tail-flip speed of kuruma shrimp, Marsupenaeus japonicus (9.92+/-0.60 cm, 10.18+/-1.89 g) were determined at 25-26 degrees C. Metabolite concentrations in hemolymph, pleopods and abdominal muscles, and hepatopancreas were measured before exercise and immediately after exercise fatigue to evaluate physiological effect of exercise in M. japonicus. ...
Maes Michael - - 2009
PURPOSE OF REVIEW: The aim of this paper is to review recent findings on inflammatory and oxidative and nitrosative stress (IO&NS) pathways in chronic fatigue and somatization disorder. RECENT FINDINGS: Activation of IO&NS pathways is the key phenomenon underpinning chronic fatigue syndrome (CFS): intracellular inflammation, with an increased production of ...
Billaut François - - 2009
Females have often been reported to have a greater muscle fatigue resistance than males, especially during exercise at low-to-moderate intensities. Differences in muscle mass, muscle metabolism and voluntary activation patterns have been the primary explanations for the differences in performance and physiological responses to exercise between sexes. However, while ample ...
Tseng Benjamin Y - - 2009
BACKGROUND: Fatigue is a commonly neglected issue despite the high incidence rate reported in people post-stroke. OBJECTIVE: To explore the relationship between fatigue, aerobic fitness, and motor control in people with chronic stroke. METHODS: Nine people post-stroke participated in this cross-sectional study (7 females, mean age = 56.8 (11.8) years, ...
Ament Wim - - 2009
Physical exercise affects the equilibrium of the internal environment. During exercise the contracting muscles generate force or power and heat. So physical exercise is in fact a form of mechanical energy. This generated energy will deplete the energy stocks within the body. During exercise, metabolites and heat are generated, which ...
Schwartz Fabiano P FP Department of Electrical Engineering, University of Brasília, Brasília, DF 70910-900 Brazil. - - 2009
Efficiency of muscular work is usually measured as the relationship between work load and maximum exercise duration. The present study analyzes the efficiency feature as a ratio between mechanical work (WK) and the energy (E) of the surface electromyographic signal (SEMG). This relation (WK/E(SEMG)) was compared with the most common ...
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