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Seifert Thomas - - 2011
This review focuses on the possibility that autonomic activity influences cerebral blood flow (CBF) and metabolism during exercise in humans. Apart from cerebral autoregulation, the arterial carbon dioxide tension, and neuronal activation, it may be that the autonomic nervous system influences CBF as evidenced by pharmacological manipulation of adrenergic and ...
Gallagher Michael M - - 2011
Fire suppression and rescue is a physiologically demanding occupation due to extreme external heat as well as the physical and thermal burden of the protective garments. These conditions challenge body temperature homeostasis and results in heat stress. Accurate field assessment of core temperature is complex and unreliable. The present investigation ...
Beylot Michel - - 2011
Perilipin 1 is involved in the control of adipose tissue triacylglycerol hydrolysis. Its ablation in mice decreases fat mass and induces a partial resistance to diet-induced and genetic obesity. However, the consequences of perilipin 1 invalidation on energy balance are not fully defined. Moreover, the impact of perilipin 1 ablation ...
Laitano Orlando - - 2011
Exercise in the heat enhances oxidative stress markers in the human circulation, but the contribution of active skeletal muscle and the influence of hydration status remain unknown. To address this question, we measured leg exchange of glutathione (GSH), glutathione disulfide (GSSG), superoxide dismutase activity (SOD) and isoprostanes in seven males ...
Keramidas Michail E - - 2011
Aim:  To investigate the effect of carbon monoxide (CO) in the inspired air as anticipated during peak hours of traffic in polluted megalopolises on cerebral, respiratory and leg muscle oxygenation during a constant-power test. In addition, since O(2) breathing is used to hasten elimination of CO from the blood, we ...
Prochnau Dirk - - 2011
AimsIt is not clear whether cardiac resynchronization therapy (CRT) should only be optimized at rest or whether it is necessary to perform CRT optimization during exercise. Our study aims to answer this question by using an inert gas rebreathing method (Innocor(®)).Methods and resultsTwenty-seven patients with congestive heart failure and implanted ...
Belfry Glen R - - 2011
This study compared the oxygen uptake (VO(2)) and muscle deoxygenation (∆HHb) of two intermittent protocols to responses during continuous constant load cycle exercise in males (24 year ± 2, n = 7). Subjects performed three protocols: (1) 10 s work/5 s active recovery (R), R at 20 W (INT1): (2) 10 s work/5 s R, R at moderate intensity (INT2); ...
Sim Marc - - 2011
The effect of carbohydrate (CHO) consumption during prolonged endurance running on post-exercise inflammation and hepcidin levels was investigated. Eleven well-trained male endurance athletes completed a graded exercise test, followed by two experimental running trials in a randomized order. The two experimental trials consisted of a 90 min run at 75% of ...
Wax Benjamin - - 2011
The purpose of this study was to investigate the effects of carbohydrate ingestion on force output and time to exhaustion using single leg static contractions superimposed with brief periods of electromyostimulation. Six trained male subjects participated in a randomized, counterbalanced, double blind study. Subjects were randomly assigned to placebo (PL) ...
Corbett Jo - - 2011
PURPOSE:: To examine the influence of head to head (HH) competition on performance, pacing strategy, and bioenergetics, during a 2,000-m cycling task. METHODS:: Fourteen participants completed three, 2,000-m familiarization time trials (TTs) on a Velotron cycle ergometer, before completing an additional TT and a 2,000-m simulated HH competition in a ...
Mitchell Jere H - - 2011
Not applicable. Commissioned historical symposium report.
Laveneziana Pierantonio - - 2011
Rationale: Patients with COPD primarily describe their exertional dyspnea using descriptors alluding to increased effort or work of breathing and unsatisfied inspiration or inspiratory difficulty. Objective: The purpose of this study was to examine the impact of changes in dynamic respiratory mechanics during incremental (INCR) and high-intensity constant work-rate (CWR) ...
Hasson Rebecca E - - 2011
Racial differences in psychological determinants of exercise exist between non-Hispanic blacks (blacks) and non-Hispanic whites (whites). To date, no study has examined racial differences in the psychological responses during and after exercise. The objective of this study was to compare psychological outcomes of single exercise bouts in blacks and whites. ...
Jaber Jefferson - - 2011
Rate control is an acceptable alternative to rhythm control in patients with chronic atrial fibrillation (AF). The aim of this study of AF patients was to understand the correlation between their exercise capacity and both heart rate (HR) and HR variation index during exercise. The exercise capacity of 85 male ...
Buchheit Martin - - 2011
To examine physiological responses to submaximal field running with changes of direction (COD), and to compare two approaches to assess running economy (RE) with COD, ie, during square-wave (SW) and incremental (INC) exercises. Ten male team-sport athletes performed, in straight-line or over 20 m shuttles, one maximal INC and four ...
Sato Katsufumi - - 2011
Emperor penguins (Aptenodytes forsteri), both at sea and at an experimental dive hole, often have minimal surface periods even after performance of dives far beyond their measured 5.6 min aerobic dive limit (ADL: dive duration associated with the onset of post-dive blood lactate accumulation). Accelerometer-based data loggers were attached to ...
Boren Kristen - - 2011
Previous research studies by Bolga, Ayotte, and Distefano have examined the level of muscle recruitment of the gluteal muscles for various clinical exercises; however, there has been no cross comparison among the top exercises from each study. The purpose of this study is to compare top exercises from these studies ...
Casey Darren P - - 2011
Reductions in oxygen availability (O(2)) by either reduced arterial O(2) content or reduced perfusion pressure can have profound influences on the circulation, including vasodilation in skeletal muscle vascular beds. The purpose of this review is to put into context the present evidence regarding mechanisms responsible for the local control of ...
Martin A Daniel AD Department of Physical Therapy, College of Public Health and Health Professions, University of Florida, Gainesville, - - 2011
Most patients with chronic obstructive pulmonary disease (COPD) complain of dyspnea during and following exercise, and the development of intrinsic positive end-expiratory pressure (PEEP) is thought to contribute to lung hyperinflation and dyspnea. Many people with COPD use pursed lip breathing (PLB) in an attempt to produce extrinsic PEEP to ...
Sun Jing Ping - - 2011
BackgroundAtrioventricular (AV) delay in cardiac resynchronisation therapy (CRT) recipients are typically optimised at rest. However, there are limited data on the impact of exercise-induced changes in heart rate on the optimal AV delay and left ventricular function.Methods and resultsThe authors serially programmed AV delays in 41 CRT patients with intrinsic ...
de Morree Helma M - - 2011
We have recently demonstrated that electromyogram (EMG) amplitude of the frowning muscles correlates with perception of effort during leg-extension exercise. However, during aerobic exercise the relationship between facial EMG and perception of effort has never been investigated. The aim of the present study was to investigate whether facial EMG reflects ...
Herrick Jeffrey E - - 2011
PURPOSE: This study compared the metabolic and performance effects of riding front only suspension (FS) and front-and-rear suspension (FRS) mountain bicycles on an offroad course that simulated competitive cross-country race conditions (>105 min duration, with ~70% of time spent riding uphill). METHOD: Seven competitive mountain bikers (73.8±7.6 kg; 61.0±4.3 mL·kg-1·min-1) ...
Pryor Riana R - - 2011
Pryor, RR, Sforzo, GA, and King, DL. Optimizing power output by varying repetition tempo. J Strength Cond Res 25(X): 000-000, 2011-The effects of varying interrepetition rest and eccentric velocity on power output (PO) and the number of repetitions performed during a bench press set were examined in 24 college-aged resistance ...
Gorman Mark W - - 2011
During exercise coronary blood flow increases to match the augmented myocardial oxygen demand due to tachycardia. Coronary vasodilation during exercise is via a combination of feedforward and feedback control mechanisms. Feedforward control is mediated by sympathetic beta-adrenoceptor vasodilation. Feedback vasodilator control is via a novel hypothesis where adenine nucleotides released ...
Rietschier Helena L - - 2011
Rietschier, HL, Henagan, TM, Earnest, CP, Baker, BL, Cortez, CC, and Stewart, LK. Sun-dried raisins are a cost-effective alternative to sports jelly beans in prolonged cycling. J Strength Cond Res 25(X): 000-000, 2011-The purpose of this study was to examine the effects of a natural carbohydrate (CHO) source in the ...
Giordano Rose M - - 2011
Metabolites of the cytochrome P450 (CYP) pathway may contribute to vasodilation of the vasculature. However, it is not known if exercise affects their circulating concentrations. We determined effects of exercise intensity and duration on plasma concentrations of epoxy and dihydroxy metabolites of arachidonic acid. Our goal was to delineate the ...
Rogers Robert S - - 2011
The time course of changes in plasma bone turnover markers following an acute bout of resistance training (RT) or plyometrics (PLY) has not been well characterized. This study is the first to compare the acute response of bone formation and resorption markers to a single bout of RT or PLY. ...
Rønnestad Bent R - - 2011
Rønnestad, BR, Nymark, BS, and Raastad, T. Effects of in-season strength maintenance training frequency in professional soccer players. J Strength Cond Res 25(X): 000-000, 2011-The aim of the present study was to examine the effect of in-season strength maintenance training frequency on strength, jump height, and 40-m sprint performance in ...
Schmitz J P J - - 2012
Muscle fiber conduction velocity (MFCV) has often been shown to decrease during standardized fatiguing isometric contractions. However, several studies have indicated that the MFCV may remain constant during fatiguing dynamic exercise. It was investigated if these observations can be related to the absence of a large decrease in pH and ...
Jensen Dennis - - 2011
We examined the effects of dead space loading (DSL) on ventilation (V˙E), neural respiratory drive (EMGdi%max, diaphragm EMG expressed as a % of maximal EMGdi), contractile respiratory muscle effort (Pes,tidal%P(Imax), tidal esophageal pressure swing expressed as a % of maximal inspiratory Pes) and exertional dyspnea intensity ratings in 11 healthy ...
Eijsvogels T M H - - 2011
Maintaining a proper fluid balance is important during exercise as athletes are prone to develop dehydration during exercise. Although several factors may regulate the fluid balance, little is known about the role of sex during prolonged moderate-intensity exercise. Therefore, we compared body mass changes and fluid balance parameters in men ...
Murias Juan M - - 2011
The relationship between the adjustment of muscle deoxygenation (Δ[HHb]) and phase II V(O(2p)) during moderate-intensity exercise was examined before (Mod 1) and after (Mod 2) a bout of heavy-intensity "priming" exercise. Moderate intensity V(O(2p)) and Δ[HHb] kinetics were determined in 18 young males (26 ± 3 yr). V(O(2p)) was measured ...
Betts James A - - 2011
Nocturnal endocrine responses to exercise performed in the evening and the potential role of nutrition are poorly understood. To gain novel insight, 10 healthy men ingested carbohydrate with (C+P) and without (C) protein in a randomized order and double-blind manner during 2 hr of interval cycling followed by resistance type ...
Lambourne Kate - - 2011
Sixteen healthy college students performed a multiple-trial referenced temporal generalization task and an episodic temporal generalization task before and during moderate-intensity aerobic exercise. The same tasks were performed in a resting control condition. Working memory tasks were also administered before, during, and after exercise to determine whether exercise affected working ...
- - 2011
Results of new research indicate that, contrary to previous thinking, youth do not have less effective thermoregulatory ability, insufficient cardiovascular capacity, or lower physical exertion tolerance compared with adults during exercise in the heat when adequate hydration is maintained. Accordingly, besides poor hydration status, the primary determinants of reduced performance ...
Hannah R - - 2011
This study examined the acute effects of whole-body vibration (WBV) on knee joint position sense and indices of neuromuscular function, specifically strength, electromechanical delay and the rate of force development. Electromyography and electrically evoked contractions were used to investigate neural and contractile responses to WBV. Fourteen healthy males completed two ...
Kuo T B J - - 2011
Hippocampal theta wave can be induced by running and is linked to cognitive functions. The initiation and maintenance of hippocampal theta during a complete course of running, however, is not well understood. Using a treadmill exercise model, this study wirelessly recorded the hippocampal electroencephalogram, nuchal electromyogram, electrocardiogram, and three-dimensional accelerations ...
Lederle Amy - - 2011
Sequential swallowing is the act of swallowing multiple times, without pausing. Because sequential swallowing requires breath-holding, it seems likely that it could increase the drive to breathe. This study was designed to determine if sequential swallowing is accompanied by an increased drive to breathe in young, healthy adults. We predicted ...
Zhang Min - - 2011
Jaw clenching (clenching) is the result of an isometric contraction of jaw closing muscles. Because of the location of working muscles and afferent information during tooth contact, the effect of clenching on the cerebral and systemic circulation might differ from that of isometric limb exercise. This study aimed to investigate ...
Bocchi Edimar Alcides - - 2011
Background: The origin of dyspnea in chronic heart failure (HF) is multifactorial, and excessive ventilation is thought to play a role in inducing this symptom. Chemosensivity is augmented in HF, correlates with increased pulmonary ventilation (VE), and is an adverse prognostic marker. Despite increased blood levels of natriuretic peptides in ...
Lovell R - - 2011
This study compared the effects of whole body vibration (WBV) and a field-based re-warm-up during half-time (HT) on subsequent physical performance measures during a simulated soccer game. Ten semi-professional male soccer players performed 90-min fixed-intensity soccer simulations (SAFT(90) ), using a multi-directional course. During the HT period players either remained ...
Brown M B - - 2011
Sweat Na(+) concentration ([Na(+)]) varies greatly among individuals and is particularly high in cystic fibrosis (CF). The purpose of this study was to determine whether excess sweat [Na(+)] differentially impacts thirst drive and other physiological responses during progressive dehydration via exercise in the heat. Healthy subjects with high-sweat [Na(+)] (SS) ...
Morris David M - - 2011
The authors sought to determine the effects of oral lactate consumption on blood bicarbonate (HCO3-) levels, pH levels, and performance during high-intensity exercise on a cycle ergometer. Subjects (N = 11) were trained male and female cyclists. Time to exhaustion (TTE) and total work were measured during high-intensity exercise bouts ...
Scott Graham R - - 2011
Birds that fly at high altitudes must support vigorous exercise in oxygen-thin environments. Here I discuss the characteristics that help high fliers sustain the high rates of metabolism needed for flight at elevation. Many traits in the O(2) transport pathway distinguish birds in general from other vertebrates. These include enhanced ...
Hackney Kyle J - - 2011
The recovery of muscle size and function following musculoskeletal unloading has received little attention in the scientific literature. Nutritional factors such as total energy, protein intake, and the pre- and/or post-exercise consumption of amino acid-carbohydrate (AACHO) have been shown to be important for enhancing training adaptations in recreational exercisers. A ...
Brubaker Peter - - 2011
Underwater treadmill (UTM) exercise is being used with increased frequency for rehabilitation of injured athletes, yet there has been little research conducted on this modality. To determine the cardiorespiratory responses of UTM vs land treadmill (LTM) exercise, particularly with respect to the relationship between heart rate (HR) and oxygen consumption ...
Wong S Heung-Sang - - 2011
This study examined the rehydration achieved by drinking different beverages during a short-term recovery period (REC) after exercise-induced dehydration. Thirteen well-trained men (age 22.1 ± 3.3 yr, body mass 61.2 ± 9.1 kg, VO2max 64.9 ± 4.0 ml · kg-1 · min-1, maximum heart rate 198 ± 7 beats/min) ran ...
Girard Olivier - - 2011
Short-duration sprints (<10 seconds), interspersed with brief recoveries (<60 seconds), are common during most team and racket sports. Therefore, the ability to recover and to reproduce performance in subsequent sprints is probably an important fitness requirement of athletes engaged in these disciplines, and has been termed repeated-sprint ability (RSA). This ...
Crisafulli Antonio - - 2011
We hypothesized that the role of stroke volume (SV) in the metaboreflex-induced cardiac output (CO) increase was blunted when the metaboreflex was stimulated by exercise muscle ischemia (EMI) compared with post-exercise muscle ischemia (PEMI), because during EMI heart rate (HR) increases and limits diastolic filling. Twelve healthy volunteers were recruited ...
Camata Thiago V - - 2011
Camata, TV, Altimari, LR, Bortolotti, H, Dantas, JL, Fontes, EB, Smirmaul, BPC, Okano, AH, Chacon-Mikahil, MPT, and Moraes, AC. Electromyographic activity and rate of muscle fatigue of the quadriceps femoris during cycling exercise in the severe domain. J Strength Cond Res 25(X): 000-000, 2011-This study compared the activation pattern and ...
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