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Gutierrez Guillermo - - 2009
A recent observational study in a large cohort of critically ill patients confirms the association between hyperlactatemia and mortality. The mechanisms regulating the rates of lactate production and clearance in critical illness remain poorly understood. During exercise, hyperlactatemia clearly results from an imbalance between oxygen delivery and energy requirements. In ...
Myers Jonathan J Cardiology Division, Veterans Affairs Palo Alto Health Care System and Stanford University , Palo Alto, - - 2009
An impaired cardiac output (CO) response to exercise is a hallmark of chronic heart failure (CHF), and the degree to which CO is impaired is related to the severity of CHF and prognosis. However, practical methods for obtaining cardiac output during exercise are lacking, and what constitutes and impaired response ...
Binder Ronald K - - 2008
Determination of an 'anaerobic threshold' plays an important role in the appreciation of an incremental cardiopulmonary exercise test and describes prominent changes of blood lactate accumulation with increasing workload. Two lactate thresholds are discerned during cardiopulmonary exercise testing and used for physical fitness estimation or training prescription. A multitude of ...
Liu Changlu - - 2009
Lactic acid is a well known metabolic by-product of intense exercise, particularly under anaerobic conditions. Lactate is also a key source of energy and an important metabolic substrate, and it has also been hypothesized to be a signaling molecule directing metabolic activity. Here we show that GPR81, an orphan G-protein-coupled ...
Cai Tian-Quan - - 2008
Heavy exercise or oxygen deficit often links with higher levels of arterial lactate and lower levels of plasma free fatty acids (FFA). Treatment with lactate reduces circulating levels of FFA in vivo and lipolysis in adipose tissues in vitro. However, the underlying mechanism has remained unclear. Here we employ pharmacological ...
Ribeiro Luiz Fernando Paulino - - 2009
This study analyzed the influence of recovery phase manipulation after hyperlactemia induction on the lactate minimum intensity during treadmill running. Twelve male runners (24.6 +/- 6.3 years; 172 +/- 8.0 cm and 62.6 +/- 6.1 kg) performed three lactate minimum tests involving passive (LMT(P)) and active recoveries at 30%vVO(2max) (LMT(A30)) ...
Liu Tsung-Han - - 2009
Arginine supplementation has been shown to alleviate endothelial dysfunction and improve exercise performance through increasing nitric oxide production in patients with cardiopulmonary diseases. In addition, arginine supplementation could decrease accumulations of lactate and ammonia, metabolites involved in development of muscular fatigue. The aim of this study was to investigate the ...
Quistorff Bjørn - - 2008
The human brain releases a small amount of lactate at rest, and even an increase in arterial blood lactate during anesthesia does not provoke a net cerebral lactate uptake. However, during cerebral activation associated with exercise involving a marked increase in plasma lactate, the brain takes up lactate in proportion ...
Folke M - - 2008
The lactate threshold is used by athletes to optimise the intensity during exercise. It is of interest to measure the threshold on the very day and during the present sport activity. Steady state ergometer tests have been performed on 40 individuals to compare the threshold found by an electro acoustic ...
Pardono Emerson - - 2008
In this study, we compared the maximal lactate steady state (MLSS) with lactate minimal (LM) intensities determined visually and through a quadratic polynomial function of selected stages of LM test. Eleven male recreational cyclists (27.7 +/- 4.5 years, 175.7 +/- 5.6 cm, 69.5 +/- 10.8 kg, and 12.0 +/- 5.5% ...
Maciel José Eduardo S - - 2008
The present study showed that the lactate/glucose ratio in the hemolymph of Chasmagnathus granulatus maintained in normoxia (controls) was 4.9, suggesting that lactate is an important substrate for this crab. Periods of hypoxia are part of the biological cycle of this crab, and lactate is the main end product of ...
Andrade B Ramírez - - 2008
Lactation artificially induced (ART) by steroid hormones and natural lactation (NAT) after lambing were compared in 2 dairy sheep breeds (Manchega and Lacaune) in 2 experiments conducted during winter and spring. In experiment 1, ART ewes (14 Manchega and 9 Lacaune) were induced into lactation in winter by the standard ...
Chen Albert P - - 2008
The development of dynamic nuclear polarization in solution has enabled in vivo 13C MR studies at high signal-to-noise ratio following injection of prepolarized 13C substrates. While prior studies have demonstrated the ability to observe metabolism following injection of hyperpolarized 13C pyruvate, the goal of this study was to develop and ...
Ørngreen M C - - 2008
OBJECTIVE: It is unclear to what extent muscle phosphorylase b kinase (PHK) deficiency is associated with exercise-related symptoms and impaired muscle metabolism, because 1) only four patients have been characterized at the molecular level, 2) reported symptoms have been nonspecific, and 3) lactate responses to ischemic handgrip exercise have been ...
Timinkul Akkaranee - - 2008
A mechanism by which exercise improves brain function may be attributed to increase in cerebral blood volume (CBV) with physical activity. However, the exact exercise intensity that influences CBV is still uncertain. To clarify this issue, 10 healthy young male participants were asked to perform a graded cycling exercise to ...
Green M J - - 2008
This study investigated cow characteristics, farm facilities, and herd management strategies during the dry period to examine their joint influence on somatic cell counts (SCC) in early lactation. Data from 52 commercial dairy farms throughout England and Wales were collected over a 2-yr period. For the purpose of analysis, cows ...
Ero─člu Hüseyin - - 2008
OBJECTIVES: Purpose of this study is to research the effects of acute L-Carnitine intake on badminton players' metabolic and blood lactate values. DESIGN: A total of 16 Turkish national badminton players (8 male, 8 female) were voluntarily participated into study. MaxVO2, MET, energy consumption, HR (heart rate), VE (minute ventilation), ...
Gladden L Bruce - - 2008
In September 2006, at the Integrative Physiology of Exercise meeting in Indianapolis, IN, a symposium entitled "Current Trends in Lactate Metabolism" was presented. This short paper introduces two papers from that symposium. The first paper by L. Bruce Gladden briefly summarizes key pieces of evidence that support the cell-to-cell lactate ...
Hashimoto Takeshi - - 2008
The intracellular lactate shuttle (ILS) hypothesis holds that lactate produced as the result of glycolysis and glycogenolysis in the cytosol is balanced by oxidative removal in mitochondria of the same cell. Also, the ILS is a necessary component of the previously described cell-cell lactate shuttle (CCLS), because lactate supplied from ...
McKinnon William - - 2008
Acidosis is a major factor that determines the upper limit of exercise endurance. We have previously shown that anions usually associated with intermediary metabolism are elevated in critically ill patients with metabolic acidosis and contribute significantly to acidosis generation. This study was to determine whether volunteers with normal metabolism would ...
Amtmann John A - - 2008
Lactate and rate of perceived exertion (RPE) was monitored in 6 male subjects training for and competing in a mixed martial arts event held in Butte, Montana, to determine 1) the metabolic demands of the sport and 2) the effectiveness of the prebout interval training programs chosen to help prepare ...
Tr??mper C - - 2009
OBJECTIVE: To determine if a heart rate-based protocol for bronchial provocation testing ensures sufficient exercise intensity for inducing exercise-induced bronchial obstruction. PARTICIPANTS: 100 clinically healthy non-asthmatic sports students. DESIGN: Subjects underwent an exercise challenge test (ECT) on a treadmill ergometer for bronchial provocation according to the guidelines of the American ...
Strupler M - - 2009
OBJECTIVE: To find the individual intensity for aerobic endurance training, the lactate minimum test (LMT) seems to be a promising method. LMTs described in the literature consist of speed or work rate-based protocols, but for training prescription in daily practice mostly heart rate is used. The aim of the present ...
Prestel Jügen - - 2008
Homozygous mutations in the PINK1 gene have been shown to cause early-onset parkinsonism. Here, we describe a novel homozygous mutation (Q126P), identified in two affected German sisters with a clinical phenotype typical for PINK1-associated parkinsonism. We analysed lactate, pyruvate, carnitine and acylcarnitine blood levels, lactate levels under exercise and in ...
Bourdon Pitre C - - 2009
Testing to determine blood lactate thresholds for prescription of rowing training is usually conducted separately from performance testing (i.e. 2000m time trial). The purpose of this study was to investigate whether the testing required to determine blood lactate thresholds and performance in elite rowers could be reduced by undertaking a ...
Yazici Zubeyde - - 2008
OBJECTIVES: The aim of this study was to investigate the effects of intraperitoneal (IP) boron administration on leptin and lactate levels in swimming exercise in ovariectomized rats. METHODS: Eighty adult female rats were equally allocated into 8 groups. Group 1; Control, Group 2; exercise control, Group 3; ovariectomized control, Group ...
Grishina E V - - 2008
Administration of substrates of energy metabolism in combination with hypoxen (sulfur-containing oligoquinone) promoted the increase in blood lactate concentration during maximum exercise, accelerated lactate utilization, and reduced the lactate/pyruvate ratio during recovery. The in vivo effects are in line with hypoxen capacity to accelerate in vitro oxidation of exogenous NADH ...
Plato P A - - 2008
Lactate threshold is an important reference point when setting training intensities for endurance athletes. Ventilatory threshold has been used as a noninvasive estimate of lactate threshold, but appears to underestimate training intensity for many athletes. This study evaluated whether data obtained during a noninvasive, maximal exercise test could be used ...
Karapetian G K - - 2008
The purpose of this study was to determine if changes in heart rate variability during incremental exercise could be used to estimate lactate threshold and ventilatory threshold in healthy adults. Twenty-four adults performed graded maximal cycle ergometry to volitional fatigue. Blood lactate, heart rate, RR interval, and respiratory gas exchange ...
Godfrey R J - - 2009
PURPOSE: Increased blood lactate concentration has been suggested as a primary stimulus for the exercise-induced growth hormone response (EIGR). Patients with McArdle disease are unable to produce lactate in response to exercise and thus offer a unique model to assess the role of lactate in the EIGR. Accordingly, McArdle's patients ...
Cichota Luiz Carlos - - 2008
Chronic kidney disease (CKD) is highly prevalent, with increasing numbers of patients affected by the disease world-wide, and anemia is a common finding in patients with CKD. Anemia impacts negatively on cardiovascular disease, exercise capacity, and quality of life, resulting in significant mortality and morbidity. The aim of this study ...
Connes Philippe - - 2008
Growing evidence suggests that physiological responses during exercise in sickle cell trait (SCT) carriers might differ from persons with normal haemoglobin. Epidemiological and experimental results support the view that SCT carriers could be advantaged in certain anaerobic activities, but the underlying physiological and bio-cellular mechanisms remain unknown. Maximal aerobic physical ...
Cybulski Jacek - - 2008
A new group of quaternary ammonium lactate based ionic liquids have been prepared and characterized. Didecyldimethylammonium (DDA) and benzalkonium (BA) D,L- and L-lactates are air-stable, hydrophilic, surface-active salts. They are very effective antibacterial and antifungal agents, especially the DDA lactates, against Streptococcus mutants and Candida albicans. Their activities are comparable ...
Greenwood James D - - 2008
The aim of this study was to examine the effects of active versus passive recovery on blood lactate disappearance and subsequent maximal performance in competitive swimmers. Fourteen male swimmers from the University of Virginia swim team (mean age 20.3 years, s= 4.1; stature 1.85 m, s= 2.2; body mass 81.1 ...
Leicht Christof - - 2008
The aim of the present study was to compare blood lactate elimination between individuals with paraplegia (P) and able-bodied (AB) individuals after strenuous arm exercise. Eight P and 8 AB men (matched for age, height, and weight) participated in this study. Average weekly arm-training volume for P participants (eg, hand ...
Venckunas Tomas T Department of Applied Physiology and Sports Medicine, Lithuania Academy of Physical Education , Kaunas, - - 2008
Competitive athletics is often associated with moderate left ventricular (LV) hypertrophy, and it has been hypothesized that training mode and type of exercise modulates long-term cardiac adaptation. The purpose of the study was to compare cardiac structure and function among athletes of various sports and sedentary controls. Standard transthoracic two-dimensional ...
Soller Babs R - - 2008
The intensity of exercise above which oxygen uptake (Vo2) does not account for all of the required energy to perform work has been associated with lactate accumulation in the blood (lactate threshold, LT) and elevated carbon dioxide output (gas exchange threshold). An increase in hydrogen ion concentration ([H+]) is approximately ...
Baron B - - 2008
OBJECTIVE: The purpose of this study was to measure physiological responses during exercise performed until exhaustion at the exercise intensity corresponding to the maximal lactate steady state (MLSS) in order to determine why subjects stopped. METHODS: Eleven male trained subjects performed a test at MLSS on a cycle ergometer until ...
Baillie Yvonne - - 2007
PURPOSE: This study looked at the physiological effects of performance in Highland-dance competition to consider whether the traditional methods used during class and rehearsal provide an appropriate training stimulus toward this performance. METHODS: Nine championship standard, female Highland dancers (age 14.2 +/- 1.47 years) had their heart rate and blood ...
Jofré Anna - - 2007
Enterocins A and B and sakacin K at 200 and 2,000 activity units (AU)/cm2, nisin at 200 AU/cm2, 1.8% potassium lactate, and a combination of 200 AU/cm2 of nisin and 1.8% lactate were incorporated into interleavers, and their effectiveness against Listeria monocytogenes spiked in sliced, cooked ham was evaluated. Antimicrobial-packaged ...
Davis James A - - 2007
The lactate threshold (LT) represents the onset of a metabolic acidosis during graded exercise testing (GXT). It is a valuable measurement in clinical exercise testing and correlates well with endurance performance. Our purpose was to compare three LT detection methods, namely, Inspection (work rate at onset of a systematic increase ...
Navalta James W - - 2007
Dynamic activities such as running, cycling, and swimming have been shown to effectively reduce lactate in the postexercise period. It is unknown whether core stabilization exercises performed following an intense bout would exhibit a similar effect. Therefore, this study was designed to assess the extent of the lactate response with ...
Johnson S T - - 2008
AIM: Physical activity and metformin are often used concomitantly in the treatment of diabetes, even though little is known about possible interactions between these treatment modalities. This study was designed to examine the acute effect of metformin on oxygen consumption and lactate concentration during exercise. METHODS: Eleven healthy, active men ...
Nuntaporn Egtasaeng
Thesis (M.Sc.)--Chulalongkorn University, 2000
Volianitis S - - 2008
Intense exercise decreases the cerebral metabolic ratio of O(2) to carbohydrates (glucose + (1/2) lactate) and the cerebral lactate uptake depends on its arterial concentration, but whether these variables are influenced by O(2) availability is not known. In six males, maximal ergometer rowing increased the arterial lactate to 21.4 +/- ...
Newell John - - 2007
Blood lactate markers are used as summary measures of the underlying model of an athlete's blood lactate response to increasing work rate. Exercise physiologists use these endurance markers, typically corresponding to a work rate in the region of high curvature in the lactate curve, to predict and compare endurance ability. ...
Drinkard Bart - - 2007
Peak oxygen uptake (VO2peak) is frequently difficult to assess in overweight individuals; therefore, submaximal measures that predict VO2peak are proposed as substitutes. Oxygen uptake efficiency slope (OUES) has been suggested as a submaximal measurement of cardiorespiratory fitness that is independent of exercise intensity. There are few data examining its value ...
Gasparovic Hrvoje - - 2007
OBJECTIVE: The etiology of lung injury following cardiopulmonary bypass (CPB) is multifactorial. Our study focused on quantifying the lactate release from the lungs precipitated by extracorporeal circulation at different time points after the insult. This was complemented by an evaluation of the gas exchange at the level of the alveolar-capillary ...
de Araujo Gustavo Gomes - - 2007
The lactate minimum test (LACmin) has been considered an important indicator of endurance exercise capacity and a single session protocol can predict the maximal steady state lactate (MLSS). The objective of this study was to determine the best swimming protocol to induce hyperlactatemia in order to assure the LACmin in ...
Caruso John F - - 2007
INTRODUCTION: Historically, exercise performance outcomes may be predicted with anthropometric variables such as body mass. To assess body mass and resistance exercise (REX) performance variable correlations to blood lactate values, subjects performed five different workouts on two devices that do not employ gravitational resistance. One device uses flywheels to impose ...
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