A method for calculating lactate production rate using blood lactate concentration during exercise in mice

We evaluated whether elevated blood lactate concentration during exercise in anemia is the result of elevated production or reduced clearance. Female Sprague-Dawley rats were made acutely anemic by exchange transfusion of plasma for whole blood. Hemoglobin and hematocrit were reduced 33%, to 8.6 +/- 0.4 mg/dl and 26.5 +/- 1.1%, respectively. Blood lactate kinetics were studied by primed continuous infusion of [U-14C]lactate. Blood flow distribution during rest and exercise was determined from injection of 153Gd- and 113Sn-labeled microspheres. Resting blood glucose (5.1 +/- 0.2 mM) and lactate (1.9 +/- 0.02 mM) concentrations were not different in anemic animals. However, during exercise blood glucose was lower in anemic animals (4.0 +/- 0.2 vs. 4.6 +/- 0.1 mM) and lactate was higher (6.1 +/- 0.4 vs. 2.3 +/- 0.5 mM). Blood lactate disposal rates (turnover measured with recyclable tracer, Ri) were not different at rest and averaged 136 +/- 5.8 mumol.kg-1.min-1. Ri was significantly elevated in both control (260.9 +/- 7.1 mumol.kg-1.min-1) and anemic animals (372.6 +/- 8.6) during exercise. Metabolic clearance rate (MCR = Ri/[lactate]) did not differ during rest (151 +/- 8.2 ml.kg-1.min-1); MCR was reduced more by exercise in anemic animals (64.3 +/- 3.8) than in controls (129.2 +/- 4.1). Plasma catecholamine levels were not different in resting rats, with pooled mean values of 0.45 +/- 0.1 and 0.48 +/- 0.1 ng/ml for epinephrine (E) and norepinephrine (NE), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

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Metabolic recovery from exhaustive activity by a large lizard

Journal of Applied Physiology ◽

10.1152/jappl.1980.48.4.689 ◽

1980 ◽

Vol 48 (4) ◽

pp. 689-694 ◽

Cited By ~ 21

Author(s):

T. T. Gleeson

Keyword(s):

Temperature Dependence ◽

Blood Lactate ◽

Lactate Concentration ◽

Lactate Production ◽

Blood Lactate Concentration ◽

Excess Oxygen ◽

Temporal Separation ◽

Metabolic Recovery ◽

Strenuous Activity ◽

Lactate Removal

Gas exchange (VO2 and VCO2) and blood lactate concentration were measured in the lizard Amblyrhynchus cristatus at 25 and 35 degrees C during resting, running, and recovery after exhaustion (less than or equal to 180 min) to analyze the temperature dependency of metabolic recovery in this lizard. Amblyrhynchus exhausted twice as fast (4.2 vs. 8.8 min) at 25 degrees C than when running at the same speed at 35 degrees C. At both temperatures, VO2 and VCO2 increased rapidly during activity and declined toward resting levels during recovery in a manner similar to other vertebrates. Respiratory quotients (R, where R = VCO2/VO2) exceeded 2.0 after exhaustion at both temperatures. Extensive lactate production occurred during activity; blood lactate concentrations ranged from 1.0 to 1.7 mg lactate/ml blood after activity. Net lactate removal exhibited a temperature dependence. Blood lactate concentrations remained elevated hours after VO2 returned to normal. Endurance was reduced in lizards that had recovered aerobically but still possessed high lactate concentrations. The temporal separation of the excess oxygen consumption and lactate removal suggests that the concept of the lactacid oxygen debt is not applicable to this animal. The temperature dependence of total metabolic recovery suggests a benefit for Amblyrhynchus that select warm basking temperatures following strenuous activity.

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Effect of endurance training on activators of glycolysis in muscle during exercise

Journal of Applied Physiology ◽

10.1152/jappl.1994.76.2.846 ◽

1994 ◽

Vol 76 (2) ◽

pp. 846-852 ◽

Cited By ~ 12

Author(s):

C. Duan ◽

W. W. Winder

Keyword(s):

Endurance Training ◽

Blood Lactate ◽

Lactate Concentration ◽

Lactate Production ◽

Blood Lactate Concentration ◽

Quadriceps Muscle ◽

Muscle Lactate ◽

Cyclic Monophosphate ◽

Lactate Levels ◽

Exercise Induced

Endurance training attenuates exercise-induced increases in blood lactate at the same submaximal work rate. Three intramuscular compounds that influence muscle lactate production were measured in fasted non-trained (NT) and endurance-trained (T) rats. The T rats were subjected to a progressive endurance-training program. At the end of the program (11 wk), they were running 2 h/day at 31 m/min up a 15% grade 5 days/wk. NT and T rats were fasted for 24 h and then anesthetized (pentobarbital, iv) at rest or after running for 30 min at 21 m/min (15% grade). Blood lactate levels were significantly lower in the T rats than in the NT rats after 30 min of running (2.3 +/- 0.2 vs. 3.9 +/- 0.2 mM). The lower blood lactate concentration was accompanied by lower plasma epinephrine (2.8 +/- 0.4 vs. 6.0 +/- 0.8 nM), adenosine 3′, 3′,5′-cyclic monophosphate (0.36 +/- 0.02 vs. 0.50 +/- 0.03 pmol/mg), mg), glucose 1,6-diphosphate (26 +/- 2 vs. 40 +/- 5 pmol/mg), and fructose 2,6-diphosphate (3.2 +/- 0.2 vs. 4.3 +/- 0.3 pmol/mg) in white quadriceps muscle in T than in NT rats. Red quadriceps muscle glucose 1,6-diphosphate and adenosine 3′,5′-cyclic monophosphate were also lower in T than in NT rats. These adaptations may be responsible in part for the lower exercise-induced blood lactate in fasted rats as a consequence of endurance training.

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The Effect of Hyperventilation on the Lactacidaemia of Muscular Exercise

Clinical Science ◽

10.1042/cs0380269 ◽

1970 ◽

Vol 38 (2) ◽

pp. 269-276 ◽

Cited By ~ 10

Author(s):

R. H. T. Edwards ◽

Marie Clode

Keyword(s):

Blood Lactate ◽

Control Period ◽

Control Level ◽

Lactate Concentration ◽

Lactate Production ◽

Blood Lactate Concentration ◽

Respiratory Muscles ◽

Cycle Ergometer ◽

Exercise Tests ◽

End Tidal

1. Six men exercised at 600 kp m/min on a cycle ergometer. After a control period they hyperventilated at about twice the control level of ventilation. Capillary blood samples were taken for lactate estimations at the end of both 6 min periods. 2. Hyperventilation resulting in a fall in end-tidal Pco2 of 12·0 mmHg was associated with rise in blood lactate concentration of 1·07 mm/l. 3. It is concluded that the increase in blood lactate concentration attributable to hyperventilation is comparatively small in exercise tests involving short periods of moderately severe exertion. 4. In an additional subject exercising similarly, hyperventilation without a fall in Pco2 (‘normocapnic’ hyperventilation) was achieved by adding 3·8% CO2 to the inspired air. Subsequent hyperventilation while breathing air resulted in a fall in end-tidal Pco2 of 19·5 mmHg (‘hypocapnic’ hyperventilation) and a rise in blood lactate concentration of 1·21 mm/l. Parallel changes in pyruvate concentration occurred suggesting that lactate production had increased. Neither the origin nor the mechanism of this increase could be ascertained; however, it appeared unlikely to be due to increased anaerobic metabolism of the respiratory muscles as normocapnic hyperventilation was associated with virtually no change in blood lactate and pyruvate concentrations.

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Estimating energy expenditure for brief bouts of exercise with acute recovery

Applied Physiology Nutrition and Metabolism ◽

10.1139/h05-013 ◽

2006 ◽

Vol 31 (2) ◽

pp. 144-149 ◽

Cited By ~ 14

Author(s):

Christopher B Scott

Keyword(s):

Energy Expenditure ◽

Total Energy ◽

Blood Lactate ◽

Lactate Concentration ◽

Lactate Production ◽

Blood Lactate Concentration ◽

Total Energy Expenditure ◽

Post Exercise ◽

Anaerobic Energy ◽

Substrate Level

Four indirect estimations of energy expenditure were examined, (i) O2 debt, (ii) O2 deficit, (iii) blood lactate concentration, and (iv) excess CO2 production during and after 6 exercise durations (2, 4, 10, 15, 30, and 75 s) performed at 3 different intensities (50%, 100%, and 200% of VO2 max). Analysis of variance (ANOVA) was used to determine if significant differences existed among these 4 estimations of anaerobic energy expenditure and among 4 estimations of total energy expenditure (that included exercise O2 uptake and excess post-exercise oxygen consumption, or EPOC, measurements). The data indicate that estimations of anaerobic energy expenditure often differed for brief (2, 4, and 10 s) bouts of exercise, but this did not extend to total energy expenditure. At the higher exercise intensities with the longest durations O2 deficit, blood lactate concentration, and excess CO2 estimates of anaerobic and total energy expenditure revealed high variability; however, they were not statistically different. Moreover, they all differed significantly from the O2 debt interpretation (p < 0.05). It is concluded that as the contribution of rapid substrate-level ATP turnover with lactate production becomes larger, the greatest error in quantifying total energy expenditure is suggested to occur not with the method of estimation, but with the omission of a reasonable estimate of anaerobic energy expenditure.Key words: O2 deficit, lactate, O2 debt, EPOC, anaerobic energy expenditure.

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Lactate clamp: a method to measure lactate utilization in vivo

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1998.275.4.e729 ◽

1998 ◽

Vol 275 (4) ◽

pp. E729-E733 ◽

Cited By ~ 2

Author(s):

Jiaping Gao ◽

Mohammad A. Islam ◽

Christine M. Brennan ◽

Beth E. Dunning ◽

James E. Foley

Keyword(s):

Blood Lactate ◽

Infusion Rate ◽

Lactate Concentration ◽

Lactate Production ◽

Blood Lactate Concentration ◽

Whole Body ◽

Lactate Utilization ◽

Lactate Infusion ◽

And Control

A lactate clamp method has been developed to quantify the whole body lactate utilization in conscious, unstressed rats. Dichloroacetate (DCA), a known lactate utilization enhancer, was used to validate the method. Fasting blood lactate concentrations before the clamps were identical for DCA-treated (1 mmol/kg) and control groups (1.65 ± 0.37 vs. 1.65 ± 0.19 mM). The animals received a primed continuous lactate infusion for 90 min at variable rates to clamp the blood lactate concentration at 2 mM. The steady-state (60–90 min) lactate infusion rate, which represents the whole body lactate utilization in DCA-treated animals, was 144% higher than that in the control animals (13.2 ± 1.0 vs. 5.4 ± 1.1 mg ⋅ kg−1 ⋅ min−1; P < 0.001). The markedly increased lactate infusion rate indicates an enhanced lactate flux by DCA. To determine whether the increased lactate infusion by DCA reflected reduced endogenous lactate production, lactate production was measured. The results indicate that endogenous lactate production was not affected by DCA. In conclusion, the lactate clamp provides a sensitive and reliable method to assess lactate utilization in vivo, a dynamic measurement that may not be clearly demonstrated by blood lactate concentrations per se.

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The influence of execution speed on blood lactate concentration in strength training protocol in bench press exercise

Revista Brasileira de Fisiologia do Exercício ◽

10.33233/rbfe.v19i1.3990 ◽

2020 ◽

Vol 19 (1) ◽

pp. 32

Author(s):

Gustavo Taques Marczynski ◽

Luís Carlos Zattar Coelho ◽

Leonardo Emmanuel De Medeiros Lima ◽

Rodrigo Pereira Da Silva ◽

Dilmar Pinto Guedes Jr ◽

...

Keyword(s):

Strength Training ◽

Blood Lactate ◽

Bench Press ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

The Third ◽

Fast Speed ◽

Work Volume ◽

Execution Speed ◽

Training Protocol

The aim of this study was to analyze the influence of two velocities of execution relative to blood lactate concentration in strength training exercise until the momentary concentric failure. Fifteen men (29.1 ± 5.9 years), trained, participated in the experiment. The volunteers performed three bench press sessions, with an interval of 48 hours between them. At the first session, individuals determined loads through the 10-12 RMs test. In the following two sessions, three series with 90 seconds of interval were performed, in the second session slow execution speed (cadence 3030) and later in the third session fast speed (cadence 1010). For statistical analysis, the Student-T test was used for an independent sample study and considered the value of probability (p) ≤ 0.05 statistically significant. By comparing the number of repetitions and time under tension of the two runs, all series compared to the first presented significant reductions (p < 0.05). The total work volume was higher with the fast speed (p < 0.05). The study revealed that rapid velocities (cadence 1010) present a higher concentration of blood lactate when compared to slow runs (cadence 3030). The blood lactate concentration, in maximum repetitions, is affected by the speed of execution.Keywords: resistance training, cadence, blood lactate.

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RELATIONSHIPS BETWEEN RECALL OF PERCEIVED EXERTION AND BLOOD LACTATE CONCENTRATION IN A JUDO COMPETITION

Perceptual and Motor Skills ◽

10.2466/pms.92.3.1139-1148 ◽

2001 ◽

Vol 92 (3) ◽

pp. 1139 ◽

Cited By ~ 7

Author(s):

MIGUEL ANGEL SERRANO

Keyword(s):

Blood Lactate ◽

Perceived Exertion ◽

Lactate Concentration ◽

Blood Lactate Concentration

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Effects of cocaine on incremental treadmill exercise in horses

Journal of Applied Physiology ◽

10.1152/jappl.1993.75.6.2727 ◽

1993 ◽

Vol 75 (6) ◽

pp. 2727-2733 ◽

Cited By ~ 10

Author(s):

K. H. McKeever ◽

K. W. Hinchcliff ◽

D. F. Gerken ◽

R. A. Sams

Keyword(s):

Right Ventricular ◽

Blood Lactate ◽

Venous Blood ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

Ventricular Pressure ◽

Mixed Venous Blood ◽

Work Intensity ◽

Venous Blood Lactate ◽

Mixed Venous

Four mature horses were used to test the effects of two doses (50 and 200 mg) of intravenously administered cocaine on hemodynamics and selected indexes of performance [maximal heart rate (HRmax), treadmill velocity at HRmax, treadmill velocity needed to produce a blood lactate concentration of 4 mmol/l, maximal mixed venous blood lactate concentration, maximal treadmill work intensity, and test duration] measured during an incremental treadmill test. Both doses of cocaine increased HRmax approximately 7% (P < 0.05). Mean arterial pressure was 30 mmHg greater (P < 0.05) during the 4- to 7-m/s steps of the exercise test in the 200-mg trial. Neither dose of cocaine had an effect on the responses to exertion of right atrial pressure, right ventricular pressure, or maximal change in right ventricular pressure over time. Maximal mixed venous blood lactate concentration increased 41% (P < 0.05) with the 50-mg dose and 75% (P < 0.05) with the 200-mg dose during exercise. Administration of cocaine resulted in decreases (P < 0.05) in the treadmill velocity needed to produce a blood lactate concentration of 4 mmol/l from 6.9 +/- 0.5 and 6.8 +/- 0.9 m/s during the control trials to 4.4 +/- 0.1 m/s during the 200-mg cocaine trial. Cocaine did not alter maximal treadmill work intensity (P > 0.05); however, time to exhaustion increased by approximately 92 s (15%; P < 0.05) during the 200-mg trial.(ABSTRACT TRUNCATED AT 250 WORDS)

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Peripheral Modulators of the Central Fatigue Development and Their Relationship with Athletic Performance in Jumper Horses

Animals ◽

10.3390/ani11030743 ◽

2021 ◽

Vol 11 (3) ◽

pp. 743

Author(s):

Francesca Arfuso ◽

Claudia Giannetto ◽

Elisabetta Giudice ◽

Francesco Fazio ◽

Michele Panzera ◽

...

Keyword(s):

Blood Lactate ◽

Athletic Performance ◽

Lactate Concentration ◽

Indirect Evidence ◽

Blood Lactate Concentration ◽

Central Fatigue ◽

Serotoninergic System ◽

Stressful Situation ◽

Passive Behavior ◽

Fatigue Development

The current study aimed to investigate whether peripheral modulators of serotoninergic function and neurohumoral factors’ changes in athletic horses during an official jumping competition, and to evaluate their relationship with the physical performance of competing horses. From 7 Italian Saddle mares (6–9 years; mean body weight 440 ± 15 kg), performing the same standardized warm-up and jumping course during an official class, heart rate (HR) was monitored throughout the competition. Rectal temperature (RT) measurement, blood lactate and glucose concentration, serum tryptophan, leucine, valine, the tryptophan/branched-chain amino-acids ratio (Try/BCAAs), dopamine, prolactin, and non-esterified fatty acids (NEFAs) were assessed before the exercise event (T0), at the end of the competition stage (5 min ± 10 s following the cessation of the exercise, TPOST5), and 30 min after the end of competition (TPOST30). Highest HR values were recorded during the course and at the outbound (p < 0.0001); blood lactate concentration and RT increased after exercise with respect to the rest condition (p < 0.0001). Lower leucine and valine levels (p < 0.01), and higher tryptophan, Try/BCAAs ratio, and NEFAs values were found at TPOST5 and TPOST30 with respect to T0 (p < 0.0001). A higher prolactin concentration was found at TPOST5 and TPOST30 compared to T0 (p < 0.0001), whereas dopamine showed decreased values after exercise compared to rest (p < 0.0001). Statistically significant correlations among the peripheral indices of serotoninergic function, neurohumoral factors, and athletic performance parameters were found throughout the monitoring period. The findings provide indirect evidence that the serotoninergic system may be involved in fatigue during jumper exercise under a stressful situation, such as competition, in which, in addition to physical effort, athletic horses exhibit more passive behavior.

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