Catecholamine response is attenuated during moderate-intensity exercise in response to the “lactate clamp”

Catecholamine release is known to be regulated by feedforward and feedback mechanisms. Norepinephrine (NE) and epinephrine (Epi) concentrations rise in response to stresses, such as exercise, that challenge blood glucose homeostasis. The purpose of this study was to assess the hypothesis that the lactate anion is involved in feedback control of catecholamine concentration. Six healthy active men (26 ± 2 yr, 82 ± 2 kg, 50.7 ± 2.1 ml·kg−1·min−1) were studied on five occasions after an overnight fast. Plasma concentrations of NE and Epi were determined during 90 min of rest and 90 min of exercise at 55% of peak O2 consumption (V̇o2 peak) two times with exogenous lactate infusion (lactate clamp, LC) and two times without LC (CON). The blood lactate profile (∼4 mM) of a preliminary trial at 65% V̇o2 peak (65%) was matched during the subsequent LC trials. In resting men, plasma NE concentration was not different between trials, but during exercise all conditions were different with 65% > CON > LC (65%: 2,115 ± 166 pg/ml, CON: 1,573 ± 153 pg/ml, LC: 930 ± 174 pg/ml, P < 0.05). Plasma Epi concentrations at rest were different between conditions, with LC less than 65% and CON (65%: 68 ± 9 pg/ml, CON: 59 ± 7 pg/ml, LC: 38 ± 10 pg/ml, P < 0.05). During exercise, Epi concentration showed the same trend (65%: 262 ± 37 pg/ml, CON: 190 ± 34 pg/ml, LC: 113.2 ± 23 pg/ml, P < 0.05). In conclusion, lactate attenuates the catecholamine response during moderate-intensity exercise, likely by feedback inhibition.

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Effect of Moderate-Intensity Exercise Versus Activities of Daily Living on 24-Hour Blood Glucose Homeostasis in Male Patients With Type 2 Diabetes

Diabetes Care ◽

10.2337/dc12-2620 ◽

2013 ◽

Vol 36 (11) ◽

pp. 3448-3453 ◽

Cited By ~ 69

Author(s):

J.-W. van Dijk ◽

M. Venema ◽

W. van Mechelen ◽

C. D. A. Stehouwer ◽

F. Hartgens ◽

...

Keyword(s):

Type 2 Diabetes ◽

Blood Glucose ◽

Activities Of Daily Living ◽

Glucose Homeostasis ◽

Daily Living ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Blood Glucose Homeostasis ◽

Male Patients

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Recreational Exercise Before and During Pregnancy in Relation to Plasma C-Reactive Protein Concentrations in Pregnant Women

Journal of Physical Activity and Health ◽

10.1123/jpah.2013-0390 ◽

2015 ◽

Vol 12 (6) ◽

pp. 770-775 ◽

Cited By ~ 7

Author(s):

Yan Wang ◽

Lea A. Cupul-Uicab ◽

Walter J. Rogan ◽

Merete Eggesbo ◽

Gregory Travlos ◽

...

Keyword(s):

Pregnant Women ◽

Plasma Concentrations ◽

Moderate Intensity ◽

Low Grade ◽

Linear Regression Models ◽

C Reactive Protein ◽

Moderate Intensity Exercise ◽

Reactive Protein ◽

Recreational Exercise ◽

Vigorous Intensity

Background:Pregnant women who are physically active have a lower risk of preeclampsia and gestational diabetes than women who are less active. One possible mechanism is a reduction in low-grade inflammation, as measured by plasma concentrations of C-reactive protein (CRP). The association between exercise and CRP in pregnant women, however, has not been adequately investigated.Methods:A total of 537 pregnant women, enrolled around the 17th week of gestation in the Norwegian Mother and Child Cohort Study in 2003 to 2004, were studied. Self-reported recreational exercise was recalled for both 3 months before pregnancy and early pregnancy. The total energy expenditure from recreational exercise (total recreational exercise, metabolic equivalent of task [MET]-hr/week) was estimated, and low-, moderate- and vigorous-intensity exercise was defined. Plasma CRP concentrations were measured during pregnancy.Results:In adjusted linear regression models, mean CRP concentration was 1.0% lower [95% CI = –1.9% to 0.2%] with each 1 MET-hr/week of total recreational exercise before pregnancy. In addition, vigorous-intensity exercise before pregnancy was more strongly related to a reduction in CRP levels than low- or moderate-intensity exercise. However, we observed no association between recreational exercise during pregnancy and plasma CRP levels.Conclusion:Recreational exercise before pregnancy, especially vigorous exercise, may reduce the risk of maternal inflammation during pregnancy.

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The Effect of a Short Sprint on Postexercise Whole-Body Glucose Production and Utilization Rates in Individuals with Type 1 Diabetes Mellitus

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2012-1604 ◽

2012 ◽

Vol 97 (11) ◽

pp. 4193-4200 ◽

Cited By ~ 54

Author(s):

A. J. Fahey ◽

N. Paramalingam ◽

R. J. Davey ◽

E. A. Davis ◽

T. W. Jones ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 1 Diabetes ◽

Blood Glucose ◽

Type 1 Diabetes Mellitus ◽

Whole Body ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Glucose Levels ◽

Blood Glucose Levels

Context: Recently we showed that a 10-sec maximal sprint effort performed before or after moderate intensity exercise can prevent early hypoglycemia during recovery in individuals with type 1 diabetes mellitus (T1DM). However, the mechanisms underlying this protective effect of sprinting are still unknown. Objective: The objective of the study was to test the hypothesis that short duration sprinting increases blood glucose levels via a disproportionate increase in glucose rate of appearance (Ra) relative to glucose rate of disappearance (Rd). Subjects and Experimental Design: Eight T1DM participants were subjected to a euglycemic-euinsulinemic clamp and, together with nondiabetic participants, were infused with [6,6-2H]glucose before sprinting for 10 sec and allowed to recover for 2 h. Results: In response to sprinting, blood glucose levels increased by 1.2 ± 0.2 mmol/liter (P < 0.05) within 30 min of recovery in T1DM participants and remained stable afterward, whereas glycemia rose by only 0.40 ± 0.05 mmol/liter in the nondiabetic group. During recovery, glucose Ra did not change in both groups (P > 0.05), but glucose Rd in the nondiabetic and diabetic participants fell rapidly after exercise before returning within 30 min to preexercise levels. After sprinting, the levels of plasma epinephrine, norepinephrine, and GH rose transiently in both experimental groups (P < 0.05). Conclusion: A sprint as short as 10 sec can increase plasma glucose levels in nondiabetic and T1DM individuals, with this rise resulting from a transient decline in glucose Rd rather than from a disproportionate rise in glucose Ra relative to glucose Rd as reported with intense aerobic exercise.

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Hormonal and metabolic responses to exercise across time of day and menstrual cycle phase

Journal of Applied Physiology ◽

10.1152/jappl.1997.83.6.1822 ◽

1997 ◽

Vol 83 (6) ◽

pp. 1822-1831 ◽

Cited By ~ 60

Author(s):

E. A. Galliven ◽

A. Singh ◽

D. Michelson ◽

S. Bina ◽

P. W. Gold ◽

...

Keyword(s):

Menstrual Cycle ◽

Adrenocorticotropic Hormone ◽

Plasma Concentrations ◽

Time Of Day ◽

Moderate Intensity ◽

Cycle Phase ◽

Menstrual Cycle Phase ◽

Short Term ◽

Moderate Intensity Exercise ◽

Hormonal Responses

Galliven, E. A., A. Singh, D. Michelson, S. Bina, P. W. Gold, and P. A. Deuster. Hormonal and metabolic responses to exercise across time of day and menstrual cycle phase. J. Appl. Physiol. 83(6): 1822–1831, 1997.—Two studies, each utilizing short-term treadmill exercise of a different intensity, assessed the metabolic and hormonal responses of women to exercise in the morning (AM) and late afternoon (PM). In study 1, plasma concentrations of growth hormone, arginine vasopressin, catecholamines, adrenocorticotropic hormone, cortisol, lactate, and glucose were measured before, during, and after high-intensity exercise (90% maximal O2 uptake) in the AM and PM. In study 2, plasma concentrations of adrenocorticotropic hormone, cortisol, lactate, and glucose were measured before, during, and after moderate-intensity exercise (70% maximal O2 uptake) in the AM and PM in the follicular ( days 3–9), midcycle ( days 10–16), and luteal ( days 18–26) phases of the menstrual cycle. The results of studies 1 and 2 revealed no significant diurnal differences in the magnitude of responses for any measured variable. In addition, study 2 revealed a significant time-by-phase interaction for glucose ( P = 0.014). However, net integrated responses were similar across cycle phases. These data suggest that metabolic and hormonal responses to short-term, high-intensity exercise can be assessed with equal reliability in the AM and PM and that there are subtle differences in blood glucose responses to moderate-intensity exercise across menstrual cycle phase.

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THE SIMILAR CHANGES OF GLUCOSE LEVELS BEFORE AND AFTER MODERATE INTENSITY EXERCISE ACUTELY IN THE MORNING AND NIGHT

Majalah Biomorfologi ◽

10.20473/mbiom.v30i2.2020.45-50 ◽

2020 ◽

Vol 30 (2) ◽

pp. 45

Author(s):

Ronik Harsono Kamal ◽

Kristanti Wanito Wigati ◽

Achmad Lefi

Keyword(s):

Blood Glucose ◽

Physical Exercise ◽

Asia Pacific ◽

Moderate Intensity ◽

Maximum Heart Rate ◽

Moderate Intensity Exercise ◽

Glucose Levels ◽

Blood Glucose Levels ◽

Before And After ◽

The Mean

Background: There is a lot of research on the importance of exercise but studies on the effective time of exercise regarding regulation of blood glucose levels are not clearly known. Objective: This study aims to determine the comparison of changes in blood glucose levels before and after moderate intensity physical exercise in the morning and night. Material and method: Healthy men (n=34), Age between 17-22 years, Body Mass Index (BMI) between 18.5-22.9 kg/m2 (normal Asia Pacific), participating in the morning group (8.00 am) or the night group (20.00 pm) are asked to do moderate intensity physical exercise (55-70% of maximum heart rate) using ergocycle for a total of 40 minutes. Blood glucose levels 2 hours post prandial capillaries are taken before exercise and blood glucose levels after exercise are taken acutely. Result: The mean decrease in blood glucose levels in the morning group was -8.353±9.16 mg/dL and in the night group was -6.294±10.10 mg/dL. Blood glucose levels decreased significantly for the morning group (p=0.002) and the night group (p=0.021). The comparison of changes in blood glucose levels between the morning and night groups was not significant (p=0.538). Conclusion: There is no difference between morning or night exercise related to changes in blood glucose levels.

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Metabolic responses to exercise after fasting

Journal of Applied Physiology ◽

10.1152/jappl.1986.61.4.1363 ◽

1986 ◽

Vol 61 (4) ◽

pp. 1363-1368 ◽

Cited By ~ 48

Author(s):

G. L. Dohm ◽

R. T. Beeker ◽

R. G. Israel ◽

E. B. Tapscott

Keyword(s):

Blood Glucose ◽

Blood Glucose Concentration ◽

Human Subjects ◽

Plasma Concentrations ◽

Exercise Bout ◽

Liver Glycogen ◽

Glycogen Depletion ◽

Fat Mobilization ◽

Blood Glucose Homeostasis ◽

Beta Hydroxybutyrate

Fasting before exercise increases fat utilization and lowers the rate of muscle glycogen depletion. Since a 24-h fast also depletes liver glycogen, we were interested in blood glucose homeostasis during exercise after fasting. An experiment was conducted with human subjects to determine the effect of fasting on blood metabolite concentrations during exercise. Nine male subjects ran (70% maximum O2 consumption) two counterbalanced trials, once fed and once after a 23-h fast. Plasma glucose was elevated by exercise in the fasted trial but there was no difference between fed and fasted during exercise. Lactate was significantly higher (P less than 0.05) in fasted than fed throughout the exercise bout. Fat mobilization and utilization appeared to be greater in the fasted trial as evidenced by higher plasma concentrations of free fatty acids, glycerol, and beta-hydroxybutyrate as well as lower respiratory exchange ratio in the fasted trial during the first 30 min of exercise. These results demonstrate that in humans blood glucose concentration is maintained at normal levels during exercise after fasting despite the depletion of liver glycogen. Homeostasis is probably maintained as a result of increased gluconeogenesis and decreased utilization of glucose in the muscle as a result of lowered pyruvate dehydrogenase activity.

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Ten days of exercise training reduces glucose production and utilization during moderate-intensity exercise

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1994.266.1.e136 ◽

1994 ◽

Vol 266 (1) ◽

pp. E136-E143 ◽

Cited By ~ 18

Author(s):

L. A. Mendenhall ◽

S. C. Swanson ◽

D. L. Habash ◽

A. R. Coggan

Keyword(s):

Endurance Training ◽

Time Course ◽

Plasma Concentrations ◽

Glucose Production ◽

Peak Oxygen Uptake ◽

Cycle Ergometer ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Ergometer Exercise ◽

Exercise Induced

We have previously shown that 12 wk of endurance training reduces the rate of glucose appearance (Ra) during submaximal exercise (Coggan, A. R., W. M. Kohrt, R. J. Spina, D. M. Bier, and J. O. Holloszy. J. Appl. Physiol. 68: 990-996, 1990). The purpose of the present study was to examine the time course of and relationship between training-induced alterations in glucose kinetics and endocrine responses during prolonged exercise. Accordingly, seven men were studied during 2 h of cycle ergometer exercise at approximately 60% of pretraining peak oxygen uptake on three occasions: before, after 10 days, and after 12 wk of endurance training. Ra was determined using a primed, continuous infusion of [6,6-2H]glucose. Ten days of training reduced mean Ra during exercise from 36.9 +/- 3.3 (SE) to 28.5 +/- 3.4 mumol.min-1.kg-1 (P < 0.001). Exercise-induced changes in insulin, C-peptide, glucagon, norepinephrine, and epinephrine were also significantly blunted. After 12 wk of training, Ra during exercise was further reduced to 21.5 +/- 3.1 mumol.min-1.kg-1 (P < 0.001 vs. 10 days), but hormone concentrations were not significantly different from 10-day values. The lower glucose Ra during exercise after short-term (10 days) training is accompanied by, and may be due to, altered plasma concentrations of the major glucoregulatory hormones. However, other adaptations must be responsible for the further reduction in Ra with more prolonged training.

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