Endurance training alters basal erythrocyte MCT-1 contents and affects the lactate distribution between plasma and red blood cells in T2DM men following maximal exercise

Chronic elevated lactate levels are associated with insulin resistance in patients with type 2 diabetes mellitus (T2DM). Furthermore, lactacidosis plays a role in limiting physical performance. Erythrocytes, which take up lactate via monocarboxylate transporter (MCT) proteins, may help transport lactate within the blood from lactate-producing to lactate-consuming organs. This study investigates whether cycling endurance training (3 times/week for 3 months) alters the basal erythrocyte content of MCT-1, and whether it affects lactate distribution kinetics in the blood of T2DM men (n = 10, years = 61 ± 9, body mass index = 31 ± 3 kg/m2) following maximal exercise (WHO step-incremental cycle ergometer test). Immunohistochemical staining indicated that basal erythrocyte contents of MCT-1 protein were up-regulated (+90%, P = 0.011) post-training. Erythrocyte and plasma lactate increased from before acute exercise (= resting values) to physical exhaustion pre- as well as post-training (pre-training: +309%, P = 0.004; +360%, P < 0.001; post-training: +318%, P = 0.008; +300%, P < 0.001), and did not significantly decrease during 5 min recovery. The lactate ratio (erythrocytes:plasma) remained unchanged after acute exercise pre-training, but was significantly increased after 5 min recovery post-training (compared with the resting value) (+22%, P = 0.022). The results suggest an increased time-delayed influx of lactate into erythrocytes following an acute bout of exercise in endurance-trained diabetic men.

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Effects of acute exercise on atherogenic lipids in untreated mild hypertensive patients

Vojnosanitetski pregled ◽

10.2298/vsp0904313c ◽

2009 ◽

Vol 66 (4) ◽

pp. 313-318 ◽

Cited By ~ 3

Author(s):

Zorica Caparevic ◽

Nada Kostic ◽

Vera Celic ◽

Zoran Cosic ◽

Djordje Marina ◽

...

Keyword(s):

Acute Exercise ◽

Oxidized Ldl ◽

Cycle Ergometer ◽

Lipid Profiles ◽

Hypertensive Patients ◽

Cardiopulmonary Exercise ◽

Cycle Ergometer Test ◽

Mild Hypertensive ◽

Ergometer Test ◽

Atherogenic Lipid

Background/Aim. Exercise can positively influence risk factors associated with cardiovascular disease. The mechanisms by which exercise reduces atherogenic risk remain unknown. The aim of the present study was to investigate the effect of acute exercise (cardiopulmonary exercise cycle ergometer test) on atherogenic lipids in untreated mild hypertensive patients with or without hypercholesterolemia. This testing allows determination of exercise capacity, peak heart rate, and ventilation per minute (VE), peak oxygen uptake (pVO2) and exercise time (ET). Methods. The study group included 85 untreated mild hypertensive patients (according to VII Joint National Committee - JNC 7) divided into two subgroups: hypertensive hypercholesterolemic and hypertensive normocholesterolemic. The control group included 35 normotensive subjects divided into two subgroups: normotensive hypercholesterolemic and normotensive normocholesterolemic. Lipid profiles to determine were oxidized LDL (OxLDL) - a marker of oxidative stress, triglycerides, total cholesterol, LDL cholesterol, and HDL cholesterol, which were measured at rest and 30 minutes after the acute bout of cardiopulmonary exercise cycle ergometer test. Lipids profiles were measured by enzymatic methods. Oxidized LDL was determined by a commercially available sandwich ELISA (Mercodia AB, Uppsala, Sweden). C-reactive protein (CRP) was measured using chemiluminiscent methods (Immulite-DPC). Results. In our study OxLDL was significantly higher in hypertensive patients with atherogenic lipid profiles in basal condition, compared to the hypertensive patients without atherogenic lipid profiles and controls. There was a significant difference in CRP (p < 0.001) between hypercholesterolemics (hypertensive and normotensive) and normocholesterolemics (hypertensive and normotensive). We found increased OxLDL after exercise in both groups (hypertensive patients and normotensive), but only in the hypertensive hypercholesterolemic patients the difference was statistically significant (90.47 ? 15.31 vs. 105.94 ? 14.17 IU/L, p < 0.001). Systolic and diastolic blood pressures were significantly higher during exercise only in the hypertensive patients. There were significantly lower values of pVO2 only in hypertensive hypercholesterolemic patients. There were no significant differences between hypertensive and normotensive ones for ET and VE. In hypertensive ones we found after exercise a negative correlation between pVO2 and OxLDL (r = -0.473; p < 0.05), and pVO2 and CRP (r = -0.478; p < 0.05). We also found in normotensive normocholesterolemic patients a positive correlation between VE and systolic blood pressure (r = 0.420; p < 0.05), a negative correlation between VE and OxLDL (r = -0.421; p < 0.05), and VE and CRP (r = -0.561; p < 0.05). Conclusion. This study showed that acute exercise induces and increases oxidative stress only in untreated mild hypertensive patients with atherogenic lipid profiles. These results imply the need to normalize atherogenic lipid profile in untreated patients with mild hypertension in order to prevent an increased lipid peroxidation under acute exercise.

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Acute Effect of Auricular Vagus Nerve Stimulation on Cycle Ergometer Test and Physiological Parameters in Healthy Young Individuals: A Pilot Study

International Journal of Sports and Exercise Medicine ◽

10.23937/2469-5718/1510211 ◽

2022 ◽

Vol 8 (1) ◽

Author(s):

HATIK Sefa Haktan ◽

Pehlivanoğlu Berkay Eren ◽

ARSLAN Mesut ◽

TAŞKIN Çilem ◽

ÖZDEN Ali Veysel

Keyword(s):

Pilot Study ◽

Vagus Nerve ◽

Nerve Stimulation ◽

Vagus Nerve Stimulation ◽

Acute Effect ◽

Cycle Ergometer ◽

Physiological Parameters ◽

Cycle Ergometer Test ◽

Ergometer Test

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CHANGE OF MICROHEMOCIRCULATION UNDER CYCLE ERGOMETER TEST IN PERSONS WITH VARIOUS LEVELS OF TOLERANCE TO PHYSICAL LOAD

Human Sport Medicine ◽

10.14529/hsm180402 ◽

2018 ◽

Vol 18 (4) ◽

pp. 14-19

Author(s):

A Kharin

Keyword(s):

Cycle Ergometer ◽

Physical Load ◽

Cycle Ergometer Test ◽

Ergometer Test

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Effect of beta-blockade on the drift in O2 consumption during prolonged exercise

Journal of Applied Physiology ◽

10.1152/jappl.1988.64.2.753 ◽

1988 ◽

Vol 64 (2) ◽

pp. 753-758 ◽

Cited By ~ 15

Author(s):

J. K. Kalis ◽

B. J. Freund ◽

M. J. Joyner ◽

S. M. Jilka ◽

J. Nittolo ◽

...

Keyword(s):

Heart Rate ◽

Minute Ventilation ◽

Cycle Ergometer ◽

Beta Blockade ◽

Adrenergic Blockade ◽

Maximal Heart Rate ◽

O2 Consumption ◽

Double Blind ◽

Cycle Ergometer Test ◽

Ergometer Test

The effect of beta-adrenergic blockade on the drift in O2 consumption (VO2 drift) typically observed during prolonged constant-rate exercise was studied in 14 healthy males in moderate heat at 40% of maximal O2 consumption (VO2max). After an initial maximum cycle ergometer test to determine the subjects' control VO2max, subjects were administered each of three medications: placebo, atenolol (100 mg once daily), and propranolol (80 mg twice daily), in a randomized double-blind fashion. Each medication period was 5 days in length and was followed by a 4-day washout period. On the 3rd day of each medication period, subjects performed a maximal cycle ergometer test. On the final day of each medication period, subjects exercised at 40% of their control VO2max for 90 min on a cycle ergometer in a warm (31.7 +/- 0.3 degrees C) moderately humid (44.7 +/- 4.7%) environment. beta-Blockade caused significant (P less than 0.05) reductions in VO2max, maximal minute ventilation (VEmax), maximal heart rate (HRmax), and maximal exercise time. Significantly greater decreases in VO2max, VEmax, and HRmax were associated with the propranolol compared with the atenolol treatment. During the 90-min submaximal rides, beta-blockade significantly reduced heart rate. Substantially lower values for O2 consumption (VO2) and minute ventilation (VE) were observed with propranolol compared with atenolol or placebo. Furthermore, VO2 drift and HR drift were observed under atenolol and placebo conditions but not with propranolol. Respiratory exchange ratio decreased significantly over time during the placebo and atenolol trials but did not change during the propranolol trial.(ABSTRACT TRUNCATED AT 250 WORDS)

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The 10-min Cycle Ergometer Test

The Journal of Strength and Conditioning Research ◽

10.1519/00124278-199802000-00003 ◽

1998 ◽

Vol 12 (1) ◽

pp. 12-17

Author(s):

Paul M. Vanderburgh ◽

Greg Daniels ◽

Todd A. Crowder ◽

Tony Lachowetz ◽

Robb Elliott

Keyword(s):

Cycle Ergometer ◽

Cycle Ergometer Test ◽

Ergometer Test

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A Clinical Method for Estimation of VO2max Using Seismocardiography

International Journal of Sports Medicine ◽

10.1055/a-1144-3369 ◽

2020 ◽

Vol 41 (10) ◽

pp. 661-668

Author(s):

Kasper Sørensen ◽

Mathias Krogh Poulsen ◽

Dan Stieper Karbing ◽

Peter Søgaard ◽

Johannes Jan Struijk ◽

...

Keyword(s):

Prediction Model ◽

Cardiorespiratory Fitness ◽

Demographic Data ◽

Cycle Ergometer ◽

Accurate Estimation ◽

Clinical Method ◽

Cycle Ergometer Test ◽

Aortic Valve Closure ◽

Proposed Model ◽

Ergometer Test

AbstractThe purpose of this study was to investigate the correlation between the seismocardiogram and cardiorespiratory fitness. Cardiorespiratory fitness can be estimated as VO2max using non-exercise algorithms, but the results can be inaccurate. Healthy subjects were recruited for this study. Seismocardiogram and electrocardiogram were recorded at rest. VO2max was measured during a maximal effort cycle ergometer test. Amplitudes and timing intervals were extracted from the seismocardiogram and used in combination with demographic data in a non-exercise prediction model for VO2max. 26 subjects were included, 17 females. Mean age: 38.3±9.1 years. The amplitude following the aortic valve closure derived from the seismocardiogram had a significant correlation of 0.80 (p<0.001) to VO2max. This feature combined with age, sex and BMI in the prediction model, yields a correlation to VO2max of 0.90 (p<0.001, 95% CI: 0.83–0.94) and a standard error of the estimate of 3.21 mL·kg−1·min−1 . The seismocardiogram carries information about the cardiorespiratory fitness. When comparing to other non-exercise models the proposed model performs better, even after cross validation. The model is limited when tracking changes in VO2max. The method could be used in the clinic for a more accurate estimation of VO2max compared to current non-exercise methods.

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