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Knoepfli B - - 2004
OBJECTIVES: To compare changes in circulating energy sources during prolonged exercise in off season (OS) and pre-season (PS) training of triathletes. METHODS: Nine athletes of the Swiss national triathlon team (three female, mean (SD) age 28.7 (4.9) years, height 169.8 (6.0) cm, weight 57.0 (6.2) kg, VO(2)max 66.5 (5.3) ml/min/kg; ...
Van Schuylenbergh R - - 2004
We investigated the validity of different lactate and ventilatory threshold methods, to estimate heart rate and power output corresponding with the maximal lactate steady-state (MLSS) in elite cyclists. Elite cyclists (n = 21; 21 +/- 0.4 y; VO2peak, 5.4 +/- 0.2 l x min (-1)) performed either one (n = ...
Tuckey Nicholas - - 2004
The physiological responses to exercise and stress of the Antarctic labriform swimmer Pagothenia borchgrevinki were compared to the temperate labriform swimmers Notolabrus celidotus and Notolabrus fucicola. Basic swimming characteristics were very similar amongst the three species with P. borchgrevinki showing a reduced capacity for exercise. P. borchgrevinki showed large increases ...
Juneja V K - - 2004
Inhibition of Clostridium perfringens germination and outgrowth by salts of organic acids such as sodium lactate, sodium acetate, buffered sodium citrate and buffered sodium citrate supplemented with sodium diacetate was evaluated during continuous chilling of ground turkey. Turkey breast meat was injected with a brine-containing NaCl, potato starch and potassium ...
Gladden L B - - 2004
For much of the 20th century, lactate was largely considered a dead-end waste product of glycolysis due to hypoxia, the primary cause of the O2 debt following exercise, a major cause of muscle fatigue, and a key factor in acidosis-induced tissue damage. Since the 1970s, a 'lactate revolution' has occurred. ...
Green M J - - 2004
This research investigated somatic cell count (SCC) records during lactation, with the purpose of identifying distribution characteristics (mean and measures of variation) that were most closely associated with clinical mastitis. Three separate data sets were used, one containing quarter SCC (n = 1444) and two containing cow SCC (n = ...
Creteur Jacques - - 2004
We investigated the role of the hepatosplanchnic region in the hyperlactatemia observed during endotoxic shock. The study included 18 dogs anesthetized with pentobarbital and mechanically ventilated. After baseline measurements, including gut lactate production (GLP), liver lactate uptake (LLU), liver lactate extraction (LLE), and hepatosplanchnic lactate production (HSLP), each dog received ...
Connes Philippe - - 2004
This study investigated 1) red blood cells (RBC) rigidity and 2) lactate influxes into RBCs in endurance-trained athletes with and without exercise-induced hypoxemia (EIH). Nine EIH and six non-EIH subjects performed a submaximal steady-state exercise on a cyclo-ergometer at 60% of maximal aerobic power for 10 min, followed by 15 ...
Desvigne N - - 2004
Microdialysis presents the unique possibility to measure metabolite concentrations in human interstitial fluid. During exercise, the recovery of these metabolites should be precisely monitored since it is known to increase greatly with muscle blood flow. The loss of ethanol, perfused at low concentration, can be accurately measured and reflects the ...
Van Schuylenbergh R - - 2004
The impact of air ventilation on performance and physiological responses during stationary exercise in the laboratory was studied. Fourteen well-trained cyclists performed three exercise tests on a cycle ergometer, each separated by a 1-week interval. The first test was a graded test to determine the power output corresponding with the ...
Ong Hean-Yee - - 2004
During constant work-rate exercise above the lactic acidosis threshold, oxygen consumption fails to plateau by 3 minutes, but continues to rise slowly. This slow component correlates closely with the rise in lactate in normal subjects. We investigated if oxygen consumption during constant work-rate exercise could rise after 3 minutes in ...
McComsey Grace A - - 2004
BACKGROUND: The significance of asymptomatic hyperlactataemia is unknown. METHODS: We measured serial lactate levels in a group of HIV-infected subjects. Objectives were to identify covariates associated with hyperlactataemia, and to explore the natural history of hyperlactataemia. RESULTS: Overall, 1487 lactate measurements were performed on 396 subjects; 299 subjects had serial ...
Duncan G E - - 2004
We determined acute and chronic effects of dichloroacetate (DCA) on maximal (MAX) and submaximal (SUB) exercise responses in patients with abnormal mitochondrial energetics. Subjects (n = 9) completed a MAX treadmill bout 1 h after ingesting 25 mg/kg DCA or placebo (PL). A 15-min SUB bout was completed the next ...
Macciotta N P P - - 2004
Milk test-day records of 5728 lactations of Italian Simmental cows were analyzed with multivariate factor analysis in order to extract 2 common factors, whose scores were used as quantitative measures of 2 main features of lactation curve shape-i.e., the increasing rate of yield in the first part of lactation and ...
Asfar Pierre - - 2004
OBJECTIVE: To assess the effects of the potassium ATP (KATP) channel blocker HMR1402 (HMR) on systemic and hepato-splanchnic hemodynamics, oxygen exchange and metabolism during hyperdynamic porcine endotoxemia. DESIGN: Prospective, randomized, controlled study with repeated measures. SETTING. Animal laboratory. SUBJECTS: Eighteen pigs allocated to receive endotoxin alone (control group, CON, n=10) ...
Moriguchi Tetsushi - - 2004
We studied the changes in urinary bicarbonate, urinary pH and some physical parameters such as minute ventilation (VE), oxygen consumption (VO2), respiratory carbon dioxide (VCO2), heart rate, blood pressure, and blood lactate, before and after the submaximal exercise. Six male subjects aged 28-33 years were involved in the study. They ...
Abramson C J - - 2004
A two-year-old, intact female Sussex spaniel was presented with signs of exercise intolerance. Pre- and post-exercise serum lactate and pyruvate concentrations and urinary organic acid screening supported a diagnosis of pyruvate dehydrogenase deficiency, as previously reported in this breed. Dietary therapy was initiated for six months, during which time there ...
Bonanni Enrica - - 2004
BACKGROUND AND PURPOSE: The aim of the study was to evaluate the catecholaminergic activity and lactate concentration during exercise in normotensive patients with obstructive sleep apnoea syndrome (OSAS). PATIENTS AND METHODS: Thirteen normotensive patients affected by OSAS (mean age+/-standard error (SE), 52.6+/-2.8 yrs; mean apnoea-hypopnea index, 35.7+/-20.3) were enrolled in ...
Lindholm Harri H Laboratory Department, Division of Clinical Physiology, Helsinki University Hospital, Helsinki, Finland. - - 2004
Muscle is one of the most commonly affected organs in mitochondrial disorders, and the symptoms are often exercise related. The cardiopulmonary exercise test with the determination of lactic acid formation could give supplementary information about the exercise-induced metabolic stress and compensatory mechanisms used in these disorders. The aim of this ...
Henderson Gregory C - - 2004
We describe the isotopic exchange of lactate and pyruvate after arm vein infusion of [3-(13)C]lactate in men during rest and exercise. We tested the hypothesis that working muscle (limb net lactate and pyruvate exchange) is the source of the elevated systemic lactate-to-pyruvate concentration ratio (L/P) during exercise. We also hypothesized ...
Connes Philippe - - 2004
Previous studies showed that erythropoietin not only increases erythrocyte production but is also essential in both the synthesis and the good functioning of several erythrocyte membrane proteins, including band 3. It is still unknown whether anion and/or H(+) fluxes are modified by erythropoietin. This study aimed to evaluate the effect ...
Almarwaey Omar Ali - - 2004
The aims of this study were: (1) to identify the exercise intensity that corresponds to the maximal lactate steady state in adolescent endurance-trained runners; (2) to identify any differences between the sexes; and (3) to compare the maximal lactate steady state with commonly cited fixed blood lactate reference parameters. Sixteen ...
Sós Cs - - 2004
Endurance training aiming at eliciting further increase of physical performance of competitive athletes demands serious time and intensity constraints. In addition, very high intensity training could lead to "over-loading" frequently associated with increased concentration of plasma lactate after maximum intensity exercise and proteinuria. We hypothesized that a newly available complex ...
Shah Sachin - - 2004
OBJECTIVES: To compare the predictive value of pH, base deficit and lactate for the occurrence of moderate-to-severe hypoxic ischaemic encephalopathy (HIE) and systemic complications of asphyxia in term infants with intrapartum asphyxia. STUDY DESIGN: We retrospectively reviewed the records of 61 full-term neonates (> or =37 weeks gestation) suspected of ...
Wakshlag Joseph J - - 2004
Evaluations of biochemical changes associated with spring-style sled dog racing indicate that differences in cortisol, lactate, and serum glucose levels suggest exercise of moderate duration (but high intensity) has metabolic demands that dif-fer from those for typical endurance sled dog racing. Additionally, hematocrit, albumin, sodium, chloride, and blood urea nitrogen ...
Ozcelik O - - 2004
The purpose of this study was to investigate the validity of non-invasive lactate threshold estimation using ventilatory and pulmonary gas exchange indices under condition of acute hypoxia. Seven untrained males (21.4+/-1.2 years) performed two incremental exercise tests using an electromagnetically braked cycle ergometer: one breathing room air and other breathing ...
Franchini E - - 2003
AIM: The objective of this study was to verify the effects of active (AR) and passive recovery (PR) after a judo match on blood lactate removal and on performance in an anaerobic intermittent task (4 bouts of upper body Wingate tests with 3-min interval between bouts; 4WT). METHODS: The sample ...
Beneke R - - 2003
During the last two decades the concept of the MLSS (maximal lactate steady state) has been established. The MLSS detects the highest level of the BLC (blood lactate concentration) and the corresponding workload (MLSS workload) that can be maintained over time without continual BLC accumulation. In spite of a lack ...
Jones Andrew M - - 2003
PURPOSE: To test the hypothesis that prior heavy exercise increases the time to exhaustion during subsequent perimaximal exercise. METHODS: Seven healthy males (mean +/- SD 27 +/- 3 yr; 78.4 +/- 0.7 kg) completed square-wave transitions from unloaded cycling to work rates equivalent to 100, 110, and 120% of the ...
Dean Teresa M - - 2003
No previous exercise studies in women have assessed the effects of the normal menstrual cycle on the lactate threshold (LT) measured during a graded, maximal exercise test. This is relevant to our understanding of exercise training and metabolism in eumenorrheic women. The present study, therefore, examined the effect of menstrual ...
Hammarén Elisabet - - 2004
The aim of this study was to evaluate the usefulness of a modification of the bicycle ergometer test, the subanaerobic threshold exercise test (SATET), as a screening test for patients with mitochondrial myopathies. Since the original SATET is frequently found to be strenuous for weak patients, a new variable (relative ...
Dalsgaard Mads K - - 2004
During maximal exercise lactate taken up by the human brain contributes to reduce the cerebral metabolic ratio, O(2)/(glucose + 1/2 lactate), but it is not known whether the lactate is metabolized or if it accumulates in a distribution volume. In one experiment the cerebral arterio-venous differences (AV) for O(2), glucose ...
Green J M - - 2004
Sweat lactate indirectly reflects eccrine gland metabolism. However the potential influence of aerobic fitness on sweat lactate is not well-understood. Six males with high aerobic fitness [peak oxygen consumption ( VO(2)peak): 61.6 (2.5) ml.kg(-1).min(-1)] and seven males with low aerobic fitness [ VO(2)peak: 41.8 (6.4) ml.kg(-1).min(-1)] completed a maximal exertion ...
Abel Thomas - - 2003
OBJECTIVE: Handbiking and wheelchair racing have gained increased popularity in Germany. This is important because of the inability of wheelchair-dependent people to maintain cardiovascular health and fitness through daily activities. The purpose of this study was to evaluate the energy expenditure (EE; kcal/h) of wheelchair-dependent individuals. METHODS: Ten wheelchair racers ...
Cerretelli Paolo - - 2003
Transitions between rest and work, in either direction, and heavy exercise loads are characterized by changes of muscle pH depending on the buffer power and capacity of the tissues and on the metabolic processes involved. Among the latter, in chronological sequence: (1). aerobic glycolysis generates sizeable amounts of lactate and ...
Ribeiro L - - 2003
AIM: Lactate minimum test (LMT) has become popular in running evaluation. This study analysed the influence of different stage lengths and determination methods on lactate minimum swimming speed (LMS) and its validity for maximal lactate steady-state speed (MLSS-S) assessment. METHODS: Twelve male swimmers (19.7+/-1.6 years, 70.3+/-8.7 kg, 181.4+/-7.9 cm) randomly ...
Davidson J A - - 2003
Objectives were to develop a system to administer exercise training to dairy cows, to measure potential physiological indicators of fitness, and to assess physical fitness. Nonlactating, nonpregnant multiparous Holstein cows (n = 19) were in one of three exercise training treatments: no exercise; 1-h exercise; or 2-h exercise by walking ...
Shiraishi Koichi - - 2003
BACKGROUND: The chronic intake of alcohol affects the function of skeletal muscles. To elucidate the influence of acute alcoholic load on muscular metabolism during exercise, we analyzed expired gases to measure the volume of consumed oxygen and the volume of exhaled CO2. METHODS: Healthy volunteers were enrolled for the study. ...
Mancuso Michelangelo M Department of Neurosciences, Neurological Clinics, University of Pisa, Via Roma 67, 56126, Pisa, Italy. - - 2003
Increasing evidence indicates that mitochondrial dysfunction occurs in the central nervous system as well as in the peripheral tissues from Alzheimer's disease (AD) patients. We have recently shown that mitochondrial cytochrome c oxidase (COX) activity is significantly reduced in brain and platelets from AD patients compared to controls. In the ...
Mustafa Iqbal - - 2003
OBJECTIVE: We have investigated the role of cardiopulmonary bypass on lactate metabolism in patients undergoing uncomplicated surgery for elective coronary artery bypass grafting (CABG). DESIGN: Prospective non-randomized observational study. SETTINGS: National Cardiovascular Center. PATIENTS. Three independent groups were studied: preoperative ( n=20), postoperative with bypass (CPB, n=20) and postoperative without ...
Kelly Michael E - - 2003
BACKGROUND: Adenosine A2a receptor stimulation can increase coronary perfusion and also reduce leukocyte-mediated inflammatory responses in some conditions. Hextend is a novel colloid solution that may have antioxidant properties. All these actions might be beneficial after severe chest trauma, but have never been investigated. To fill these gaps, this study ...
Chwalbiñska-Moneta Jolanta - - 2003
The effect of oral creatine supplementation on aerobic and anaerobic performance was investigated in 16 elite male rowers during 7-day endurance training. Before and after the daily ingestion of 20 g creatine monohydrate for 5 days (Cr-Group, n=8) or placebo (Pl-Group, n=8), subjects performed two exercise tests on a rowing ...
Demura Shinichi - - 2003
This study examined the effects of an amino acid mixture supplement on physiological response and ratings of perceived exertion during submaximal cycle-ergometer exercise in 15 healthy, untrained male students. Subjects performed submaximal sustained exercise (oxygen uptake at anaerobic threshold: 54.6 +/- 12.5% of maximum oxygen uptake capacity) with a cycle-ergometer ...
Cole Louise - - 2003
OBJECTIVE: To evaluate the effect of high-volume hemofiltration (HVHF) with lactate-buffered replacement fluids on acid-base balance. DESIGN: Randomized crossover study. SETTING: Intensive Care Unit of Tertiary Medical Center PARTICIPANTS: Ten patients with septic shock and acute renal failure. INTERVENTIONS: Random allocation to 8 h of isovolemic high-volume hemofiltration (ultrafiltration rate: ...
Reinert M - - 2003
OBJECTIVE: The purpose of the study was to measure the effects of increased inspired oxygen on patients suffering severe head injury and consequent influences on the correlations between CPP and brain tissue oxygen (PtiO2) and the effects on brain microdialysate glucose and lactate. METHODS: In a prospective, observational study 20 ...
O'Reilly D St J - - 2003
The cardio-pulmonary and biochemical changes observed in a case of McArdle's disease, exercising with increasing work rates to exhaustion in the "second-wind" phase of exercise are reported for the first time. A work rate of 275-325 watts was achieved. Venous blood lactate remained unchanged throughout. The plasma ammonium level reached ...
Siciliano Gabriele - - 2003
Lower limb muscle chronic hyperactivity in hereditary spastic paraplegia (HSP) is the consequence of motor corticospinal tract involvement, which in turn has been hypothesized to be of mitochondrial origin. In order to assess skeletal muscle aerobic metabolism and sympathetic response during exercise in 10 HSP patients, we evaluated their blood ...
Roecker K - - 2003
With the expanding use of portable heart rate (HR) monitors in endurance sports, HR is increasingly used as a marker for exercise intensity. Hereby, HR at the so-called individual anaerobic threshold (IAT) is one possible reference point. However, once determined, it is often attempted to apply HR recommendations from one ...
Oliver S P - - 2003
Prepartum intramammary antibiotic infusion of heifer mammary glands at 7 or 14 d before expected parturition is an effective procedure for eliminating many infections in heifers during late gestation and for reducing the prevalence of mastitis in heifers during early lactation and throughout lactation. Mastitis pathogens were isolated from 76% ...
Svedahl Krista - - 2003
The anaerobic threshold (AnT) is defined as the highest sustained intensity of exercise for which measurement of oxygen uptake can account for the entire energy requirement. At the AnT, the rate at which lactate appears in the blood will be equal to the rate of its disappearance. Although inadequate oxygen ...
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