Endurance training affects lactate clearance, not lactate production

1983 ◽  
Vol 244 (1) ◽  
pp. E83-E92 ◽  
Author(s):  
C. M. Donovan ◽  
G. A. Brooks

Primed-continuous infusion of [2-3H]- and [U-14C]lactate was used to study the effects of endurance training (running 2 h/day at 29.4 m/min up a 15% gradient) on lactate metabolism in rats. Measurements were made under three metabolic conditions: rest (Re), easy exercise (EE, 13.4 m/min, 1% gradient) and hard exercise (HE, 26.8 m/min, 1% gradient). Blood lactate levels in trained animals increased from 1.0 +/- 0.09 mM in Re to 1.64 +/- 0.21 in EE and 2.66 +/- 0.38 in HE. Control animals also demonstrated an increase in blood lactate with increasing work rate, but values were 1.93 +/- 0.21 and 4.62 +/- 0.57 mM at EE and HE, respectively. Lactate turnover rates (RtLA) measured with [U-14C]lactate increased from 214.0 +/- 17.0 mumol.kg-1.min-1 in Re to 390.3 +/- 31.6 in EE and 518.1 +/- 56.4 in HE. No significant differences in RtLA were observed between controls and trained animals under any condition. Identical relationships between RtLA and exercise or training were obtained with [2-3H]lactate; however, the values obtained were consistently 90% higher than those observed with [U-14C]lactate. Metabolic clearance rate (MCR) for 14C was not significantly different in Re between controls and trained animals (180.6 +/- 27.7 ml.kg-1.min-1). Metabolic clearance of lactate in trained animals was 37 and 107% greater than in controls during EE and HE, respectively. Results indicate that the effect of endurance training is not on production of lactate but on its clearance from the blood.

1988 ◽  
Vol 135 (1) ◽  
pp. 119-131 ◽  
Author(s):  
C. L. Milligan ◽  
D. G. McDonald

A bolus injection of [14C]lactate was used to measure lactate turnover rates at rest and during recovery from exhaustive exercise in coho salmon (Oncorhynchus kisutch) and starry flounder (Platichthys stellatus). At rest, lactate turnover rate in salmon was almost double that in flounder (1.33 versus 0.76 mumol min-1 kg-1), which reflected the higher blood lactate level in salmon (1.00 versus 0.12 mmol l-1). From 2 to 4 h after exercise, when blood lactate levels were at their peak and constant, turnover rates were elevated in both species, though to a greater extent in salmon than in flounder (11.88 versus 2.27 mumol min-1 kg-1). Lactate concentration and turnover rate were linearly correlated in both species. The higher turnover rate in salmon was solely a consequence of the higher blood lactate levels since, at similar blood lactate concentrations, turnover rates in flounder and salmon were the same. Therefore, the lower blood lactate levels in flounder after exercise were not a consequence of higher turnover. In neither species was the turnover rate adequate to account for the rate of lactate clearance from the muscle, suggesting a large portion was retained within the muscle and metabolized in situ. Furthermore, following injection of [14C]lactate, greater than 80% of the total blood activity was recovered as lactate, indicating that little label was incorporated into other products (e.g. glucose). These data suggest that the Cori cycle plays a minimal role in the metabolism of lactate in salmon and flounder. Furthermore, at least in flounder, there was no correlation between the kinetics of lactate clearance and O2 consumption, suggesting that the classical concept of ‘O2 debt’ is not applicable in this species.


1989 ◽  
Vol 257 (5) ◽  
pp. E782-E789 ◽  
Author(s):  
C. M. Donovan ◽  
M. J. Pagliassotti

Constant infusions of cold molar lactate (178.0 +/- 1.6 mumol.kg-1.min-1), [U-14C]lactate (0.50 muCi/min), and [6-3H]glucose (0.5 muCi/min) were employed to study the effects of endurance training (running 1 h/day, at 38 m/min, 10% grade) on lactate clearance in resting, hyperlactatemic rats. Before infusion, resting blood lactate levels were not significantly different between controls, 1.10 +/- 0.04 mM, and trained animals, 1.16 +/- 0.04 mM. Lactate levels increased significantly during the infusion period, attaining steady-state mixed venous concentrations of 11.32 +/- 0.24 mM and 5.44 +/- 0.09 mM, respectively, for controls and trained animals. Lactate clearance rates, based on net lactate removal (i.e., not tracer-estimated lactate removal), were twofold greater in trained animals vs. controls, 33.0 +/- 0.7 and 15.4 +/- 0.4 ml.kg-1. min-1, respectively. Lactate specific activity values during the infusion period were not significantly different between controls, 22,243 +/- 236 dpm/mumol, and trained animals, 21,270 +/- 374 dpm/mumol, indicating similar endogenous dilution of the pyruvate-lactate pool. For both control and trained animals, essentially 100% of the 14C infused as lactate was recovered as either glucose or CO2; however, trained animals demonstrated a 25% greater rate of gluconeogenesis. At a given lactate production rate, trained animals maintain lower lactate levels through enhanced clearance via gluconeogenesis and oxidation.


1996 ◽  
Vol 90 (6) ◽  
pp. 507-510 ◽  
Author(s):  
D. A. Wright ◽  
L. G. Forni ◽  
P. Carr ◽  
D. F. Treacher ◽  
P. J. Hilton

1. Whole-blood lactate levels were measured at different rates of haemofiltration in 10 patients with acute renal failure undergoing conventional continuous haemofiltration using lactate-buffered replacement fluid. 2. The results enable both basal production rates and the metabolic clearance of lactate to be estimated in man.


1994 ◽  
Vol 76 (2) ◽  
pp. 846-852 ◽  
Author(s):  
C. Duan ◽  
W. W. Winder

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.


1986 ◽  
Vol 250 (3) ◽  
pp. R452-R458 ◽  
Author(s):  
J. M. Weber ◽  
R. W. Brill ◽  
P. W. Hochachka

Lactate and glucose turnover rates were measured by bolus injection of [U-14C]lactate and [6-3H]glucose in cannulated lightly anesthetized skipjack tuna, Katsuwonus pelamis. Our goals were to find out whether the high rates of lactate clearance reported during recovery from burst swimming in tuna could be accounted for by high blood lactate fluxes; to extend the observed correlation between lactate turnover and lactate concentration in mammals to a nonmammalian system, and to assess the importance of lactate and glucose as metabolic fuels in tuna and to compare their flux rates with values reported for mammals. Measured lactate turnover rates ranged from 112 to 431 mumol X min-1 X kg-1 and were correlated with blood lactate concentration. Glucose turnover rate averaged 15.3 mumol X min-1 X kg-1. When correcting for body mass and temperature, skipjack tuna has at least as high or even higher lactate turnover rates than those recorded for mammals. Tuna glucose turnover rate is similar to that of mammals but much higher than levels found in other teleosts. Even the highest lactate turnover rate measured in tuna cannot fully account for the rate of blood lactate clearance observed during recovery, suggesting that some of the lactate produced in skeletal muscle must be metabolized in situ. After injection of [U-14C]lactate, less than 5% of the total blood activity was recovered in glucose, suggesting that the Cori cycle is not an important pathway of lactate metabolism in tuna.


1976 ◽  
Vol 40 (3) ◽  
pp. 312-319 ◽  
Author(s):  
B. Issekutz ◽  
W. A. Shaw ◽  
A. C. Issekutz

The effect of treadmill run on the turnover rates of glucose ([2-3H]glucose) and lactate ([U-14C]lactate), on the rates of oxidation (ROX) of lactate, and its conversion to glucose (L LEADS TO G) were measured with the primed constant-infusion technique. Comparable lactate turnover rates were obtained at rest by infusing epinephrine, or Na-L(+)-lactate with or without norepinephrine. With increasing lactate levels (L) the rate of disappearance (RdL), ROX, and L leads to G increase in a linear manner. At the same lactate level, RdL, ROX, and L leads to G are significantly higher in the running dog. Exercise increased the metabolic clearance rate of lactate threefold. At rest ROX and L leads to G represented about 50% and 18–19% of RdL, respectively. The corresponding values in the running dogs were 55% and 25%, respectively. At rest about 9% of the hepatic glucose output arose from lactate while during exercise this varied from 7 to 26% depending on RdL. It is concluded that a) the working muscle produces and utilizes lactate at the same time, and b) “in vivo” the major factor which controls both ROX and gluconeogenesis is the substrate supply.


1999 ◽  
Vol 87 (5) ◽  
pp. 1684-1696 ◽  
Author(s):  
Bryan C. Bergman ◽  
Eugene E. Wolfel ◽  
Gail E. Butterfield ◽  
Gary D. Lopaschuk ◽  
Gretchen A. Casazza ◽  
...  

We evaluated the hypotheses that endurance training decreases arterial lactate concentration ([lactate]a) during continuous exercise by decreasing net lactate release (L˙) and appearance rates (Ra) and increasing metabolic clearance rate (MCR). Measurements were made at two intensities before [45 and 65% peak O2consumption (V˙o 2 peak)] and after training [65% pretrainingV˙o 2 peak, same absolute workload (ABT), and 65% posttrainingV˙o 2 peak, same relative intensity (RLT)]. Nine men (27.4 ± 2.0 yr) trained for 9 wk on a cycle ergometer, 5 times/wk at 75%V˙o 2 peak. Compared with the 65%V˙o 2 peakpretraining condition (4.75 ± 0.4 mM), [lactate]a decreased at ABT (41%) and RLT (21%) ( P < 0.05). L˙ decreased at ABT but not at RLT. Leg lactate uptake and oxidation were unchanged at ABT but increased at RLT. MCR was unchanged at ABT but increased at RLT. We conclude that 1) active skeletal muscle is not solely responsible for elevated [lactate]a; and 2) training increases leg lactate clearance, decreases whole body and leg lactate production at a given moderate-intensity power output, and increases both whole body and leg lactate clearance at a high relative power output.


2014 ◽  
Vol 54 (3) ◽  
pp. 168
Author(s):  
Keswari Aji Patriawati ◽  
Nurnaningsih Nurnaningsih ◽  
Purnomo Suryantoro

Background Sepsis is a major health problem in children and aleading cause of death. In recent decades, lactate has been studiedas a biomarker for sepsis, and as an indicator of global tissuehypoxia, increased glycolysis, endotoxin effect, and anaerobicmetabolism. Many studies h ave shown both high levels andincreased serial blood lactate level measurements to be associatedwith increased risk of sepsis mortality.Objective To evaluate serial blood lactate levels as a prognosticfactor for sepsis mortality.Methods We performed an observational, prospective study in thePediatric Intensive Care Unit (PICU) at DR. Sardjito Hospital,Yogyakarta from July to November 2012. We collected serialblood lactate specimens of children with sepsis, first at the time ofadmission, followed by 6 and 24 hours later. The outcome measurewas mortality at the end ofintensive care. Relative risks and 95%confidence intervals of the factors associated with mortality werecalculated using univariate and multivariate analyses.Results Sepsis was found in 91 (50.3%) patients admitted tothe PIW , of whom 75 were included in this study. Five patients(6. 7%) died before the 24-hour lactate collection and 39 patients(52.0%) died during the study. Blood lactate levels of ~ 4mmol;Lat the first and 24-hour specimens were associated with mortality(RR 2.9; 95%CI 1.09 to 7 .66 and RR 4.92; 95%CI 1.77 to 13.65,respectively). Lactate clearance of less than 10% at 24 hours(adjusted RR 5.3; 95% CI 1.1 to 24.5) had a significantly greaterrisk fo llowed by septic shock (adjusted RR 1.54; 95%CI 1.36 to6.4 7) due to mortality.Conclusion In children with sepsis there is a greater risk of mortalityin those with increasing or persistently high serial blood lactatelevels, as shown by less than 10% lactate clearance at 24-hours afterPIW admission.


Pharmacology ◽  
2017 ◽  
Vol 100 (5-6) ◽  
pp. 218-228 ◽  
Author(s):  
Mu-chao Wu ◽  
Wei-ran Ye ◽  
Yi-jia Zheng ◽  
Shan-shan Zhang

Metformin (MET) is the first-line drug for treating type 2 diabetes mellitus (T2DM). However, MET increases blood lactate levels in patients with T2DM. Lactate possesses proinflammatory properties and causes insulin resistance (IR). Oxamate (OXA), a lactate dehydrogenase inhibitor, can decrease tissue lactate production and blood lactate levels. This study was conducted to examine the effects of the combination of OXA and MET on inflammation, and IR in diabetic db/db mice. Supplementation of OXA to MET led to lowered tissue lactate production and serum lactate levels compared to MET alone, accompanied with further decreased tissue and blood levels of pro-inflammatory cytokines, along with better insulin sensitivity, beta-cell mass, and glycemic control in diabetic db/db mice. These results show that OXA enhances the anti-inflammatory and insulin-sensitizing effects of MET through the inhibition of tissue lactate production in db/db mice.


1984 ◽  
Vol 57 (6) ◽  
pp. 1754-1759 ◽  
Author(s):  
B. Issekutz

Dogs with indwelling catheters in the jugular vein and in the carotid artery ran on the treadmill (slope: 15%, speed: 133 m/min). Lactate turnover and glucose turnover were measured using [U-14C]lactate and [3-3H]glucose as tracers, according to the primed constant-rate infusion method. In addition, the participation of plasma glucose in lactate production (Ra-L) was measured with [U-14C]glucose. Propranolol was given either (A) before exercise (250 micrograms/kg, iv) or (B) in form of a primed infusion administered to the dog running at a steady rate. Measurements of plasma propranolol concentration showed that in type A experiments plasma propranolol fell in 45 min below the lower limit of the complete beta-blockade. In the first 15 min of work Ra-L rose rapidly; then it fell below that of the control (exercise) values. During steady exercise, the elevated Ra-L was decreased by propranolol infusion close to resting values. beta-Blockade doubled the response of glucose production, utilization, and metabolic clearance rate to exercise. In exercising dogs approximately 40-50% of Ra-L arises from plasma glucose. This value was increased by the blockade to 85-90%. It is concluded that glycogenolysis in the working muscle has a dual control: 1) an intracellular control operating at the beginning of exercise, and 2) a hormonal control involving epinephrine and the beta-adrenergic receptors.


Sign in / Sign up

Export Citation Format

Share Document