Effect of exercise on acute postprandial glucose concentrations and interleukin-6 responses in sedentary and overweight males

This study examined the effect of 2 forms of exercise on glucose tolerance and the concurrent changes in markers associated with the interleukin (IL)-6 pathways. Fifteen sedentary, overweight males (29.0 ± 3.1 kg/m2) completed 2 separate, 3-day trials in randomised and counterbalanced order. An oral glucose tolerance test (OGTT; 75 g) was performed at the same time on each day of the trial. Day 2 of each trial consisted of a single 30-min workload-matched bout of either high-intensity intermittent exercise (HIIE; alternating 100% and 50% of peak oxygen uptake) or continuous moderate-intensity exercise (CME; 60 % of peak oxygen uptake) completed 1 h prior to the OGTT. Venous blood samples were collected before, immediately after, 1 h after, and 25 h after exercise for measurement of insulin, C-peptide, IL-6, and the soluble IL-6 receptors (sIL-6R; soluble glycoprotein 130 (sgp130)). Glucose area under the curve (AUC) was calculated from capillary blood samples collected throughout the OGTT. Exercise resulted in a modest (4.4%; p = 0.003) decrease in the glucose AUC when compared with the pre-exercise AUC; however, no differences were observed between exercise conditions (p = 0.65). IL-6 was elevated immediately after and 1 h after exercise, whilst sgp130 and sIL-6R concentrations were reduced immediately after exercise. In summary, exercise was effective in reducing glucose AUC, which was attributed to improvements that took place between 60 and 120 min into the OGTT, and was in parallel with an increased ratio of IL-6 to sIL-6R, which accords with an increased activation via the “classical” IL-6 signalling pathway. Our findings suggest that acute HIIE did not improve glycaemic response when compared with CME.

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The independent and combined effects of exercise training and reducing sedentary behavior on cardiometabolic risk factors

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2013-0379 ◽

2014 ◽

Vol 39 (7) ◽

pp. 770-780 ◽

Cited By ~ 27

Author(s):

Sarah Kozey Keadle ◽

Kate Lyden ◽

John Staudenmayer ◽

Amanda Hickey ◽

Richard Viskochil ◽

...

Keyword(s):

Exercise Training ◽

Oxygen Uptake ◽

Statistical Significance ◽

Group Analysis ◽

Peak Oxygen Uptake ◽

Moderate Intensity ◽

Oral Glucose ◽

Sensitivity Index ◽

Moderate Intensity Exercise ◽

Health Related

This pilot study examined if the combination of exercise training and reducing sedentary time (ST) results in greater changes to health markers than either intervention alone. Fifty-seven overweight/obese participants (19 males/39 females) (mean ± SD; age, 43.6 ± 9.9 years; body mass index (BMI), 35.1 ± 4.6 kg·m–2) completed the 12-week study and were randomly assigned to (i) EX: exercise 5 days·week–1 for 40 min·session–1 at moderate intensity; (ii) rST: reduce ST and increase nonexercise physical activity; (iii) EX-rST: combination of EX and rST; and (iv) CON: maintain behavior. Fasting lipids, blood pressure (BP), peak oxygen uptake, BMI, and 2-h oral glucose tolerance tests were completed pre- and post-intervention. EX and EX-rST increased peak oxygen uptake by ∼10% and decreased systolic BP (both p < 0.001). BMI decreased by –3.3% (95% confidence interval: –4.6% to –1.9%) for EX-rST and –2.2% (–3.5% to 0.0%) for EX. EX-rST significantly increased composite insulin-sensitivity index by 17.8% (2.8% to 32.8%) and decreased insulin area under the curve by 19.4% (–31.4% to –7.3%). No other groups improved in insulin action variables. rST group decreased ST by 7% (∼50 min·day–1); however, BP was the only health-related outcome that improved. EX and EX-rST improved peak oxygen uptake and BMI, providing further evidence that moderate-intensity exercise is beneficial. The within-group analysis provides preliminary evidence that exercising and reducing ST may result in improvements in metabolic biomarkers that are not seen with exercise alone, though between-group differences did not reach statistical significance. Future studies, with larger samples, should examine health-related outcomes resulting from greater reductions in ST over longer intervention periods.

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Effects of increased fat availability on fat-carbohydrate interaction during prolonged exercise in men

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1998.274.4.r894 ◽

1998 ◽

Vol 274 (4) ◽

pp. R894-R902 ◽

Cited By ~ 27

Author(s):

L. Maureen Odland ◽

George J. F. Heigenhauser ◽

Denis Wong ◽

Melanie G. Hollidge-Horvat ◽

Lawrence L. Spriet

Keyword(s):

Blood Flow ◽

Pyruvate Dehydrogenase ◽

Prolonged Exercise ◽

Respiratory Exchange Ratio ◽

Venous Blood ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Muscle Lactate ◽

Blood Samples ◽

Muscle Biopsies

The study examined the existence and regulation of fat-carbohydrate interaction during low- and moderate-intensity exercise. Eight males cycled for 10 min at 40% and 60 min at 65% maximal O2 uptake (V˙o 2 max) while infused with either Intralipid and heparin (Int) or saline (Con). Before exercise, plasma arterial free fatty acid (FFA) was 0.69 ± 0.04 mM (Int) vs. 0.25 ± 0.04 mM (Con). Muscle biopsies were taken at rest and at 10, 20, and 70 min of exercise. Arterial and femoral venous blood samples and expired gases were collected simultaneously throughout exercise, and blood flow was estimated from pulmonary O2 uptake and the leg arterial-venous O2 difference. Respiratory exchange ratio was higher in Con (0.94 ± 0.01) compared with Int (0.91 ± 0.01). Mean net leg FFA uptake was higher in Int (0.16 ± 0.03 vs. 0.04 ± 0.01 mmol/min), and net lactate efflux was reduced (Int, 1.55 ± 0.36 vs. Con, 3.07 ± 0.47 mmol/min). Leg net glucose uptake was unaffected by Int. Muscle glycogen degradation was 23% lower in Int [230 ± 29 vs. 297 ± 36 mmol glucosyl units/kg dry muscle (dm)]. Pyruvate dehydrogenase activity in the a form (PDH a) was lower during Int (1.61 ± 0.17 vs. 2.22 ± 0.24 mmol ⋅ min−1 ⋅ kg wet muscle−1), and muscle citrate was higher (0.59 ± 0.04 vs. 0.48 ± 0.04 mmol/kg dm). Muscle lactate, phosphocreatine, ATP, acetyl-CoA, acetyl-carnitine, and Pi were unaffected by Int. Calculated free AMP was significantly lower in Int compared with Con at 70 min of exercise (3.3 ± 0.8 vs. 1.5 ± 0.3 μmol/kg dm). The high FFA-induced reduction in glycogenolysis and carbohydrate oxidation at 65% V˙o 2 maxappears to be due to regulation at several sites. The reduced flux through phosphorylase and phosphofructokinase during Int may have been due to reduced free AMP accumulation and increased cytoplasmic citrate. The mechanism for reduced PDH transformation to the a form is unknown but suggests reduced flux through PDH.

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PlanHab: the combined and separate effects of 16 days of bed rest and normobaric hypoxic confinement on circulating lipids and indices of insulin sensitivity in healthy men

Journal of Applied Physiology ◽

10.1152/japplphysiol.00897.2015 ◽

2016 ◽

Vol 120 (8) ◽

pp. 947-955 ◽

Cited By ~ 19

Author(s):

Elizabeth J. Simpson ◽

Tadej Debevec ◽

Ola Eiken ◽

Igor Mekjavic ◽

Ian A. Macdonald

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Venous Blood ◽

Bed Rest ◽

Postprandial Glucose ◽

Tolerance Test ◽

Normobaric Hypoxia ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Future Space

PlanHab is a planetary habitat simulation study. The atmosphere within future space habitats is anticipated to have reduced Po2, but information is scarce as to how physiological systems may respond to combined exposure to moderate hypoxia and reduced gravity. This study investigated, using a randomized-crossover design, how insulin sensitivity, glucose tolerance, and circulating lipids were affected by 16 days of horizontal bed rest in normobaric normoxia [NBR: FiO2 = 0.209; PiO2 = 133.1 (0.3) mmHg], horizontal bed rest in normobaric hypoxia [HBR: FiO2 = 0.141 (0.004); PiO2 = 90.0 (0.4) mmHg], and confinement in normobaric hypoxia combined with daily moderate intensity exercise (HAMB). A mixed-meal tolerance test, with arterialized-venous blood sampling, was performed in 11 healthy, nonobese men (25-45 yr) before (V1) and on the morning of day 17 of each intervention (V2). Postprandial glucose and c-peptide response were increased at V2 of both bed rest interventions ( P < 0.05 in each case), with c-peptide:insulin ratio higher at V2 in HAMB and HBR, both in the fed and fasted state ( P < 0.005 in each case). Fasting total cholesterol was reduced at V2 in HAMB [−0.47 (0.36) mmol/l; P < 0.005] and HBR [−0.55 (0.41) mmol/l; P < 0.005]. Fasting HDL was lower at V2 in all interventions, with the reduction observed in HBR [−0.30 (0.21) mmol/l] greater than that measured in HAMB [−0.13 (0.14) mmol/l; P < 0.005] and NBR [−0.17 (0.15) mmol/l; P < 0.05]. Hypoxia did not alter the adverse effects of bed rest on insulin sensitivity and glucose tolerance but appeared to increase insulin clearance. The negative effect of bed rest on HDL was compounded in hypoxia, which may have implications for long-term health of those living in future space habitats.

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Effects of Different Methods Used to Take Blood Samples on Blood Glucose Measurements

Clinical Nursing Research ◽

10.1177/10547738211024782 ◽

2021 ◽

pp. 105477382110247

Author(s):

Eda Ergin ◽

Ayten Zaybak

Keyword(s):

Blood Glucose ◽

Glucose Tolerance Test ◽

Venous Blood ◽

Tolerance Test ◽

Capillary Blood ◽

Oral Glucose ◽

Blood Samples ◽

Significant Difference ◽

Measurement Results ◽

Quasi Experimental

The purpose of this study is to compare whether or not there is a difference between venous and capillary blood samples in blood glucose measurements and investigate the effects of different aseptic methods used in skin cleaning before collecting blood samples on measurement results. This quasi-experimental study was conducted with 109 patients. The capillary first and second blood drop values taken from the patients after fasting and at 2 hours following 75 g oral glucose tolerance test (OGTT) and capillary and venous blood glucose values were compared. There was no significant difference between the median venous blood glucose value and the capillary second blood drop value taken after wiping the finger with alcohol. There was no significant difference between the first and second blood drop values of capillary blood glucose 2 hours after OGTT.

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Glucose area under the curve during oral glucose tolerance test as an index of glucose intolerance

Diabetology International ◽

10.1007/s13340-015-0212-4 ◽

2015 ◽

Vol 7 (1) ◽

pp. 53-58 ◽

Cited By ~ 21

Author(s):

Kazuhiko Sakaguchi ◽

Kazuo Takeda ◽

Mitsuo Maeda ◽

Wataru Ogawa ◽

Toshiyuki Sato ◽

...

Keyword(s):

Glucose Tolerance ◽

Oral Glucose Tolerance Test ◽

Glucose Intolerance ◽

Glucose Tolerance Test ◽

Area Under The Curve ◽

Tolerance Test ◽

Oral Glucose ◽

Oral Glucose Tolerance

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Interpretation of Modified Glucose Tolerance Test among Pregnant Malaysian Women

International Journal of Innovative Research in Medical Science ◽

10.23958/ijirms/vol05-i08/921 ◽

2020 ◽

Vol 5 (08) ◽

pp. 309-313

Author(s):

Muna Kh. Al-kubaisi ◽

Saad M. Al-Shibli ◽

Nilar Win

Keyword(s):

Glucose Tolerance ◽

Pregnant Women ◽

Blood Sample ◽

Blood Sugar ◽

Glucose Tolerance Test ◽

Venous Blood ◽

Tolerance Test ◽

Oral Glucose ◽

The Mean ◽

Local Protocol

Aim: Is to find the mean and two standard deviation of the serum blood sugar among pregnant women while running the modified oral glucose tolerance test (MOGTT) as screening for gestational diabetes mellitus (GDM) & to compare the readings with other protocols adopted in diagnosing GDM. Method: A cross sectional study among pregnant women running routine MOGTT at 24-28 weeks’ gestation. A total of 149 women participated in 4 months period. The test included 5 ml of venous blood sample taken after fasting for 8 hours and a second blood sample 2 hours after having 200 ml of 75 g glucose solution within 10 minutes. Results: The mean for the fasting blood sugar is 4.32 mmol/L±0.52 making value of 2SD of 5.36 mmol/l. The mean of the 2 hours glucose level was 6.11mmol/l±1.38 making the 2SD value of 8.87 mmol/l. Conclusion: Our results for the 1st reading in MOGTT is near to the value of the local protocol in diagnosing GDM. The 2 hours postprandial reading in the local protocol is fairly low when compared with our findings & with guidelines of nearby communities.

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Interplay of Dinner Timing and MTNR1B Type 2 Diabetes Risk Variant on Glucose Tolerance and Insulin Secretion: A Randomized Crossover Trial

10.2337/figshare.17122142 ◽

2022 ◽

Author(s):

Marta Garaulet ◽

Jesus Lopez-Minguez ◽

Hassan S Dashti ◽

Céline Vetter ◽

Antonio Miguel Hernández-Martínez ◽

...

Keyword(s):

Type 2 Diabetes ◽

Insulin Secretion ◽

Glucose Tolerance ◽

Area Under The Curve ◽

Serum Levels ◽

Postprandial Glucose ◽

Oral Glucose ◽

Elevated Concentration ◽

Endogenous Melatonin

Objective: We tested whether the concurrence of food intake and elevated concentration of endogenous melatonin, as occurs in late eating, results in impaired glucose control, in particular in carriers of the type 2 diabetes-associated G allele in the melatonin-receptor-1-b gene (MTNR1B). Research Design and Methods: In a Spanish natural late eating population, a randomized, cross-over study design was performed, following an 8-h fast. Each participant (n=845) underwent two evening 2-h 75g oral glucose tolerance tests (OGTT): an early condition scheduled 4 hours prior to habitual bedtime (“early dinner-timing”), and a late condition scheduled 1 hour prior to habitual bedtime (“late dinner-timing”), simulating an early and a late dinner timing, respectively. Differences in postprandial glucose and insulin responses were determined using incremental area under the curve (AUC) calculated by the trapezoidal method between early and late dinner-timing. Results: Melatonin serum levels were 3.5-fold higher in the late vs. early condition, with late dinner-timing resulting in 6.7% lower insulin area-under-the-curve (AUC) and 8.3% higher glucose AUC. In the late condition MTNR1B G-allele carriers had lower glucose tolerance than non-carriers. Genotype differences in glucose tolerance were attributed to reductions in β-cell function (Pint AUCgluc=0.009, Pint CIR=0.022, Pint DI=0.018). Conclusions: Concurrently high endogenous melatonin and carbohydrate intake, as typical for late eating, impair glucose tolerance, especially in MTNR1B G-risk-allele carriers, attributable to insulin secretion defects.

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Effects of subtracting sitting versus adding exercise on glycemic control and variability in sedentary office workers

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2014-0157 ◽

2014 ◽

Vol 39 (11) ◽

pp. 1286-1293 ◽

Cited By ~ 13

Author(s):

Jennifer M. Blankenship ◽

Kirsten Granados ◽

Barry Braun

Keyword(s):

Energy Expenditure ◽

Plasma Glucose ◽

Repeated Measures ◽

Area Under The Curve ◽

Glycemic Variability ◽

Office Workers ◽

Sitting Time ◽

Moderate Intensity ◽

Cardiometabolic Health ◽

Moderate Intensity Exercise

Recent evidence suggests that, like adding exercise, reducing sitting time may improve cardiometabolic health. There has not been a direct comparison of the 2 strategies with energy expenditure held constant. The purpose of this study was to compare fasting and postmeal glucose and insulin concentrations in response to a day with frequent breaks from sitting but no exercise versus considerable sitting plus moderate exercise. Ten sedentary overweight/obese office workers were tested in 3 conditions: (i) walking per activity guidelines (AGW): sitting for majority of workday with a 30 min pre-lunch walk; (ii) frequent long breaks (FLB): no structured exercise but frequent breaks from sitting during workday with energy expenditure matched to AGW; and (iii) frequent short breaks (FSB): number of breaks matched to FLB, but duration of breaks were shorter. Plasma glucose and insulin areas under the curve were measured in response to a meal tolerance test (MTT) at the end of the workday and interstitial glucose was evaluated throughout the day and overnight using continuous glucose monitoring. Using repeated-measures linear mixed models, area under the curve of plasma glucose or insulin after the MTT was not different between conditions. Glycemic variability was lower in FLB compared with AGW (p < 0.05), and nocturnal duration of elevated glucose (>7.8 mmol/L) was shorter after FLB (2.5 ± 2.5 min) than AGW (32.7 ± 16.4 min) or FSB (45.6 ± 29.6 min, p = 0.05). When energy expenditure was matched, breaks from sitting approximated the effects of moderate-intensity exercise on postmeal glucose and insulin responses and more effectively constrained glycemic variability.

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The Time Course of Inflammatory Biomarkers Following a One-Hour Exercise Bout in Canines: A Pilot Study

Animals ◽

10.3390/ani10030486 ◽

2020 ◽

Vol 10 (3) ◽

pp. 486

Author(s):

Wendy Pearson ◽

Julia Guazzelli Pezzali ◽

Renan Antunes Donadelli ◽

Ashley Wagner ◽

Preston Buff

Keyword(s):

Pilot Study ◽

Time Course ◽

Venous Blood ◽

Exercise Bout ◽

Exercise Stress ◽

Moderate Intensity ◽

Resolvin D1 ◽

Moderate Intensity Exercise ◽

Hunting Dogs ◽

Inflammation Resolution

There is little information available to describe the inflammatory consequences of and recovery from moderate-intensity exercise bouts in hunting dogs. The purpose of the current study is to generate pilot data on the appearance and disappearance of biomarkers of inflammation and inflammation resolution following a typical one-hour exercise bout in basset hounds. Four hounds were set out to find a scent and freely adopted running or walking over wooded terrain for approximately one hour. Venous blood samples were obtained before the exercise and at 1, 2, 4, 6, and 10 h following cessation of exercise and were analyzed for biomarkers of inflammation (prostaglandin E2 (PGE2), nitric oxide (NO), interleukin 1β (IL-1β)) tumour necrosis factor-α (TNF-α)), and inflammation resolution (resolvin D1 (RvD1)). There was an increase in inflammation one hour after the exercise, shown by a significant increase in PGE2. Following this peak, PGE2 steadily declined at the same time as RvD1 increased, with RvD1 peaking at six hours. This pilot study provides evidence that dogs that undergo an hour of hunt exercise experience transient inflammation that peaks one hour after the end of exercise; inflammation resolution peaks six hours after the end of exercise. Future studies should seek to further understand the distinct and combined roles of PGE2 and RvD1 in dog adaptation to exercise stress.

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Epinephrine inhibits exogenous glucose utilization in exercising horses

Journal of Applied Physiology ◽

10.1152/jappl.2000.88.5.1777 ◽

2000 ◽

Vol 88 (5) ◽

pp. 1777-1790 ◽

Cited By ~ 30

Author(s):

Raymond J. Geor ◽

Kenneth W. Hinchcliff ◽

Laura Jill McCutcheon ◽

Richard A. Sams

Keyword(s):

Muscle Glycogen ◽

Glucose Utilization ◽

Treadmill Exercise ◽

Moderate Intensity ◽

Oral Glucose ◽

Moderate Intensity Exercise ◽

Epinephrine Infusion ◽

Glucose Administration ◽

Exogenous Glucose ◽

Glycogen Utilization

This study examined the effects of preexercise glucose administration, with and without epinephrine infusion, on carbohydrate metabolism in horses during exercise. Six horses completed 60 min of treadmill exercise at 55 ± 1% maximum O2 uptake 1) 1 h after oral administration of glucose (2 g/kg; G trial); 2) 1 h after oral glucose and with an intravenous infusion of epinephrine (0.2 μmol ⋅ kg− 1 ⋅ min− 1; GE trial) during exercise, and 3) 1 h after water only (F trial). Glucose administration (G and GE) caused hyperinsulinemia and hyperglycemia (∼8 mM). In GE, plasma epinephrine concentrations were three- to fourfold higher than in the other trials. Compared with F, the glucose rate of appearance was ∼50% and ∼33% higher in G and GE, respectively, during exercise. The glucose rate of disappearance was ∼100% higher in G than in F, but epinephrine infusion completely inhibited the increase in glucose uptake associated with glucose administration. Muscle glycogen utilization was higher in GE [349 ± 44 mmol/kg dry muscle (dm)] than in F (218 ± 28 mmol/kg dm) and G (201 ± 35 mmol/kg dm). We conclude that 1) preexercise glucose augments utilization of plasma glucose in horses during moderate-intensity exercise but does not alter muscle glycogen usage and 2) increased circulating epinephrine inhibits the increase in glucose rate of disappearance associated with preexercise glucose administration and increases reliance on muscle glycogen for energy transduction.

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