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Malin SK, Frick H, Wisseman WS, Edwards ES, Edwards DA, Emerson SR, Kurti SP. β-Cell function during a high-fat meal in young versus old adults: role of exercise. Am J Physiol Regul Integr Comp Physiol 2023; 325:R164-R171. [PMID: 37306399 PMCID: PMC10393366 DOI: 10.1152/ajpregu.00047.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 05/23/2023] [Accepted: 06/05/2023] [Indexed: 06/13/2023]
Abstract
The acute effect of exercise on β-cell function during a high-fat meal (HFM) in young adults (YA) versus old adults (OA) is unclear. In this randomized crossover trial, YA (n = 5 M/7 F, 23.3 ± 3.9 yr) and OA (n = 8 M/4 F, 67.7 ± 6.0 yr) underwent a 180-min HFM (12 kcal/kg body wt; 57% fat, 37% CHO) after a rest or exercise [∼65% heart rate peak (HRpeak)] condition ∼12 h earlier. After an overnight fast, plasma lipids, glucose, insulin, and free fatty acid (FFA) were determined to estimate peripheral, or skeletal muscle, insulin sensitivity (Matsuda index) as well as hepatic [homeostatic model assessment of insulin resistance (HOMA-IR)] and adipose insulin resistance (adipose-IR). β-Cell function was derived from C-peptide and defined as early-phase (0-30 min) and total-phase (0-180 min) disposition index [DI, glucose-stimulated insulin secretion (GSIS) adjusted for insulin sensitivity/resistance]. Hepatic insulin extraction (HIE), body composition [dual-energy X-ray absorptiometry (DXA)], and peak oxygen consumption (V̇o2peak) were also assessed. OA had higher total cholesterol (TC), LDL, HIE, and DI across organs as well as lower adipose-IR (all, P < 0.05) and V̇o2peak (P = 0.056) despite similar body composition and glucose tolerance. Exercise lowered early-phase TC and LDL in OA versus YA (P < 0.05). However, C-peptide area under the curve (AUC), total phase GSIS, and adipose-IR were reduced postexercise in YA versus OA (P < 0.05). Skeletal muscle DI increased in YA and OA after exercise (P < 0.05), whereas adipose DI tended to decline in OA (P = 0.06 and P = 0.08). Exercise-induced skeletal muscle insulin sensitivity (r = -0.44, P = 0.02) and total-phase DI (r = -0.65, P = 0.005) correlated with reduced glucose AUC180min. Together, exercise improved skeletal muscle insulin sensitivity/DI in relation to glucose tolerance in YA and OA, but only raised adipose-IR and reduced adipose-DI in OA.NEW & NOTEWORTHY High-fat diets may induce β-cell dysfunction. This study compared how young and older adults responded to a high-fat meal with regard to β-cell function and whether exercise comparably impacted glucose regulation. Older adults secreted more insulin during the high-fat meal than younger adults. Although exercise increased β-cell function adjusted for skeletal muscle insulin sensitivity in relation to glucose tolerance, it raised adipose insulin resistance and reduced pancreatic β-cell function relative to adipose tissue in older adults. Additional work is needed to discern nutrient-exercise interactions across age to mitigate chronic disease risk.
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Affiliation(s)
- Steven K Malin
- Department of Kinesiology and Health, Rutgers University, New Brunswick, New Jersey, United States
| | - Hannah Frick
- Human Performance Laboratory, Department of Kinesiology, James Madison University, Harrisonburg, Virginia, United States
- Department of Kinesiology, Morrison Bruce Center, James Madison University, Harrisonburg, Virginia, United States
| | - William S Wisseman
- Human Performance Laboratory, Department of Kinesiology, James Madison University, Harrisonburg, Virginia, United States
| | - Elizabeth S Edwards
- Human Performance Laboratory, Department of Kinesiology, James Madison University, Harrisonburg, Virginia, United States
- Department of Kinesiology, Morrison Bruce Center, James Madison University, Harrisonburg, Virginia, United States
| | - David A Edwards
- Department of Kinesiology, University of Virginia, Charlottesville, Virginia, United States
| | - Sam R Emerson
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, Oklahoma, United States
| | - Stephanie P Kurti
- Human Performance Laboratory, Department of Kinesiology, James Madison University, Harrisonburg, Virginia, United States
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Waldman HS, Bryant AR, Knight SN, Killen LG, Davis BA, Robinson MA, O'Neal EK. Assessment of Metabolic Flexibility by Substrate Oxidation Responses and Blood Lactate in Women Expressing Varying Levels of Aerobic Fitness and Body Fat. J Strength Cond Res 2023; 37:581-588. [PMID: 35836305 DOI: 10.1519/jsc.0000000000004316] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Waldman, HS, Bryant, AR, Knight, SN, Killen, LG, Davis, BA, Robinson, MA, and O'Neal, EK. Assessment of metabolic flexibility by substrate oxidation responses and blood lactate in women expressing varying levels of aerobic fitness and body fat. J Strength Cond Res 37(3): 581-588, 2023-Collection of substrate oxidation responses during exercise is proposed as a noninvasive means for assessing metabolic flexibility in male subjects. However, because of hormonal and metabolic differences between sexes, this method may not be applicable to female subjects. This study assessed metabolic flexibility through indirect calorimetry across female subjects with different maximal oxidative capacities. Thirty-eight (18-45 years) eumenorrheic female subjects were stratified ( p < 0.05) based on V̇ o2 peak (mL·kg -1 ·min -1 ) into (1) endurance-trained (ET, n = 12, 42.6 ± 5.3), (2) recreationally active (RA, n = 13, 32.3 ± 1.6), or (3) overweight female subjects (OW, n = 13, 21.0 ± 4.0). Subjects completed the same 5-stage graded exercise test with intensities of 30, 45, 60, 75, and 90 W. Lactate [La - ], carbohydrate (CHOox), and fat (FATox) oxidation rates were assessed during the last min of each 5-minute stage. Subjects then cycled to exhaustion to determine V̇ o2 peak. Endurance-trained and RA female subjects expressed significantly ( p ≤ 0.05) higher absolute rates and rates scaled to fat-free mass of CHOox and FATox compared with OW female subjects during multiple stages. [La - ] failed to consistently differentiate the 3 groups with higher [La - ] for OW only found during stage 4; however, RER differed by 0.09 units or more at each stage for OW vs. ET. It seems that RER was more sensitive to cohort characteristics than [La - ] contrasting recent findings in male cohorts. In conclusion, indirect calorimetry is a practical and noninvasive method for assessing metabolic flexibility in eumenorrheic female subjects of varying aerobic fitness levels.
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Affiliation(s)
- Hunter S Waldman
- Human Performance Research Laboratory, Department of Kinesiology, University of North Alabama, Florence, Alabama; and
| | - Andrea R Bryant
- Human Performance Research Laboratory, Department of Kinesiology, University of North Alabama, Florence, Alabama; and
| | - Savanna N Knight
- Human Performance Research Laboratory, Department of Kinesiology, University of North Alabama, Florence, Alabama; and
| | - Lauren G Killen
- Human Performance Research Laboratory, Department of Kinesiology, University of North Alabama, Florence, Alabama; and
| | - Brett A Davis
- Department of Kinesiology, Auburn University at Montgomery, Montgomery, Alabama
| | - Marcus A Robinson
- Department of Kinesiology, Auburn University at Montgomery, Montgomery, Alabama
| | - Eric K O'Neal
- Human Performance Research Laboratory, Department of Kinesiology, University of North Alabama, Florence, Alabama; and
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Malin SK, Remchak ME, Smith AJ, Ragland TJ, Heiston EM, Cheema U. Early chronotype with metabolic syndrome favours resting and exercise fat oxidation in relation to insulin-stimulated non-oxidative glucose disposal. Exp Physiol 2022; 107:1255-1264. [PMID: 36123314 PMCID: PMC9633545 DOI: 10.1113/ep090613] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/08/2022] [Indexed: 01/11/2023]
Abstract
NEW FINDINGS What is the central question of this study? Chronotype reflects differences in circadian-mediated metabolic and hormonal profiles. But, does resting and/or exercise fuel use differ in early versus late chronotype as it relates to insulin sensitivity? What are the main finding and its importance? Early chronotypes with metabolic syndrome utilized more fat during rest and exercise independent of aerobic fitness when compared with late chronotypes. Early chronotypes were also more physically active throughout the day. Greater fat use was related to non-oxidative glucose disposal. These findings suggest that early chronotypes have differences in fuel selection that associate with type 2 diabetes risk. ABSTRACT Early chronotypes (ECs) are often insulin-sensitive, in part, due to physical activity behaviour. It is unclear, however, if chronotypes differ in resting and/or exercise fuel oxidation in relation to insulin action. Using the Morningness-Eveningness Questionnaire (MEQ), adults with metabolic syndrome (ATP III criteria) were classified as EC (MEQ = 63.7 ± 0.9, n = 24 (19F), 54.2 ± 1.2 years) or late chronotype (LC; MEQ = 47.2 ± 1.4, n = 27 (23F), 55.3 ± 1.5 years). Carbohydrate (CHO) and fat oxidation (FOX, indirect calorimetry) were determined at rest, 55% and 85% V ̇ O 2 max ${\dot{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{max}}}$ , along with heart rate and rating of perceived exertion. Physical activity patterns (accelerometers), body composition (DXA) and insulin sensitivity (clamp, 40 mU/m2 /min, 90 mg/dl) with an indirect calorimetry for non-oxidative glucose disposal (NOGD) were also determined. While demographics were similar, ECs had higher V ̇ O 2 max ${\dot{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{max}}}$ (P = 0.02), NOGD (P < 0.001) and resting FOX (P = 0.02) than LCs. Both groups increased CHO reliance during exercise at 55% and 85% V ̇ O 2 max ${\dot{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{max}}}$ (test effect, P < 0.01) from rest, although ECs used more fat (group effect, P < 0.01). ECs had lower sedentary behaviour and more physical activity during morning/midday (both, P < 0.05). FOX at 55% V ̇ O 2 max ${\dot{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{max}}}$ correlated with V ̇ O 2 max ${\dot{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{max}}}$ (r = 0.425, P = 0.004) whereas FOX at 85% V ̇ O 2 max ${\dot{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{max}}}$ related to NOGD (r = 0.392, P = 0.022). ECs with metabolic syndrome used more fat in relation to insulin-stimulated NOGD.
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Affiliation(s)
- Steven K. Malin
- Rutgers UniversityNew BrunswickNJUSA,University of VirginiaCharlottesvilleVAUSA,Division of EndocrinologyMetabolism and NutritionRutgers UniversityNew BrunswickNJUSA,New Jersey Institute for FoodNutrition and HealthRutgers UniversityNew BrunswickNJUSA,Institute of Translational Medicine and ScienceRutgers UniversityNew BrunswickNJUSA
| | | | | | | | - Emily M. Heiston
- University of VirginiaCharlottesvilleVAUSA,Virginia Commonwealth UniversityRichmondVAUSA
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Arad AD, DiMenna FJ, Kittrell HD, Kissileff HR, Albu JB. Whole body lipid oxidation during exercise is impaired with poor insulin sensitivity but not with obesity per se. Am J Physiol Endocrinol Metab 2022; 323:E366-E377. [PMID: 35830686 DOI: 10.1152/ajpendo.00042.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Equivocal findings regarding the influence of overweight/obesity on exercise lipid-oxidizing capacity (EX-LIPOX) might reflect inadequate control of 1) acute energy balance/macronutrient composition of diet; 2) intensity/duration of exercise; and/or 3) insulin sensitivity (IS) of participant. To assess independent/combined influences of IS and overweight/obesity with other factors controlled, we recruited sedentary adults with normal weight (NW; n = 15) or overweight/obesity (O; n = 15) subdivided into metabolically healthy (MH; n = 8) and unhealthy (MU; n = 7) groups (IS; MH > MU). Participants completed a 9-day, weight-stabilizing, controlled-feeding protocol comprising measurements of resting metabolism, body composition, oral glucose tolerance, and maximal exercise capacity. We measured EX-LIPOX during the initial 45 min of "steady state" during constant-work-rate cycling at 70% and 100% of participant gas-exchange threshold (GET). At 70%, average EX-LIPOX in absolute (0.11 ± 0.02 g·min-1) and relative (2.4 ± 0.3 mg·kgFFM-1·min-1) terms was lower for NW-MU than MH regardless of body composition (NW-MH, 0.19 ± 0.02 g·min-1/3.9 ± 0.3 mg·kgFFM-1·min-1; O-MH, 0.19 ± 0.02 g·min-1/3.7 ± 0.3 mg·kgFFM-1·min-1), whereas no difference was present for NW-MU and O-MU (0.15 ± 0.02 g·min-1/2.8 ± 0.3 mg·kgFFM-1·min-1). Multiple regression confirmed that with IS-controlled, overweight/obesity was not associated with decreased EX-LIPOX, whereas decreased EX-LIPOX was associated with decreased IS independent of overweight/obesity. Overweight/obesity also did not influence EX-LIPOX across MH groups or with cohort divided by body-composition classification alone (P > 0.05). Exercise lipid-oxidizing capacity is impaired with poor IS regardless of body composition, but not with overweight/obesity per se.NEW & NOTEWORTHY In this study, we have shown that the capacity to oxidize lipid during exercise is influenced by metabolic health of the exerciser regardless of body composition, but not by body composition per se. This observation refutes the belief that a reduced capacity to oxidize lipid is an obligatory characteristic of the overweight/obese condition while supporting the contention that exercise should be prescribed with specificity based on both absence/presence of overweight/obesity and compromise/lack thereof in metabolic health.
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Affiliation(s)
- Avigdor D Arad
- Division of Endocrinology, Diabetes and Bone, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
- The Integrated Center for Preventive Medicine, Tel Aviv Medical Center, Tel Aviv, Israel
| | - Fred J DiMenna
- Division of Endocrinology, Diabetes and Bone, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Hannah D Kittrell
- The Charles Bronfman Institute for Personalized Medicine, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York
- The Mount Sinai Morningside Hospital, New York, New York
| | - Harry R Kissileff
- Division of Endocrinology, Diabetes and Bone, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
- The Mount Sinai Morningside Hospital, New York, New York
| | - Jeanine B Albu
- Division of Endocrinology, Diabetes and Bone, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
- The Mount Sinai Morningside Hospital, New York, New York
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Guirado T, Bourdier P, Pereira B, Le Roux E, Bergouignan A, Birat A, Isacco L, Thivel D, Duclos M, Metz L. Metabolic profile in women differs between high versus low energy spenders during a low intensity exercise on a cycle-desk. Sci Rep 2022; 12:9928. [PMID: 35705612 PMCID: PMC9200836 DOI: 10.1038/s41598-022-14002-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 05/31/2022] [Indexed: 12/05/2022] Open
Abstract
Active-desks are emerging strategies aiming at reducing sedentary time while working. A large inter-individual variability in energy expenditure (EE) profile has been identified and has to be explored to better optimize and individualize those strategies. Thus the present study aimed at comparing the metabolic and physical profile of individuals characterized as high spenders (H-Spenders) versus low spenders (L-Spenders) based on EE during a cycle-desk low intensity exercise. 28 healthy women working in administrative positions were enrolled. Anthropometric, body composition and fasting metabolic profile parameters were assessed. EE was determined by indirect calorimetry, at rest and during a 30-min cycle-desk use. Participants were categorized as H-Spenders and L-Spenders using the median of the difference between EE at rest and during the 30-min exercise. H-Spenders had higher mean EE (p < 0.001) and carbohydrate oxidation (p = 0.009) during exercise. H-Spenders displayed higher values for fasting plasma insulin (p = 0.002) and HOMA-IR (p = 0.002) and lower values for HDL-cholesterol (p = 0.014) than L-Spenders. The percentage of body fat mass was significantly higher in H-Spenders (p = 0.034). Individuals expending more energy during a low intensity cycling exercise presented a less healthy metabolic profile compared with L-Spenders. Future studies will have to explore whether the chronic use of cycle-desks during work time can improve energy profile regarding metabolic parameters.
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Affiliation(s)
- Terry Guirado
- EA 3533, Laboratory of the Metabolic Adaptations to Exercise Under Physiological and Pathological Conditions (AME2P), BP 80026, UE3533, Clermont Auvergne University, 63170, Aubiere CEDEX, France. .,Auvergne Research Center for Human Nutrition (CRNH), 63000, Clermont-Ferrand, France. .,Department of Sport Medicine and Functional Explorations, Clermont-Ferrand University Hospital, G. Montpied Hospital, Clermont-Ferrand, France. .,INRA, UMR 1019, Clermont-Ferrand, France.
| | - Pierre Bourdier
- Université de Strasbourg, CNRS, IPHC, UMR 7178, 67000, Strasbourg, France
| | - Bruno Pereira
- Clermont-Ferrand University Hospital, Biostatistics Unit (DRCI), Clermont-Ferrand, France
| | - Elisa Le Roux
- Université de Strasbourg, CNRS, IPHC, UMR 7178, 67000, Strasbourg, France
| | - Audrey Bergouignan
- Université de Strasbourg, CNRS, IPHC, UMR 7178, 67000, Strasbourg, France.,Division of Endocrinology, Metabolism and Diabetes, Anschutz Health and Wellness Center, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Anthony Birat
- EA 3533, Laboratory of the Metabolic Adaptations to Exercise Under Physiological and Pathological Conditions (AME2P), BP 80026, UE3533, Clermont Auvergne University, 63170, Aubiere CEDEX, France.,Auvergne Research Center for Human Nutrition (CRNH), 63000, Clermont-Ferrand, France
| | - Laurie Isacco
- EA 3533, Laboratory of the Metabolic Adaptations to Exercise Under Physiological and Pathological Conditions (AME2P), BP 80026, UE3533, Clermont Auvergne University, 63170, Aubiere CEDEX, France.,Auvergne Research Center for Human Nutrition (CRNH), 63000, Clermont-Ferrand, France
| | - David Thivel
- EA 3533, Laboratory of the Metabolic Adaptations to Exercise Under Physiological and Pathological Conditions (AME2P), BP 80026, UE3533, Clermont Auvergne University, 63170, Aubiere CEDEX, France.,Auvergne Research Center for Human Nutrition (CRNH), 63000, Clermont-Ferrand, France
| | - Martine Duclos
- Auvergne Research Center for Human Nutrition (CRNH), 63000, Clermont-Ferrand, France.,Department of Sport Medicine and Functional Explorations, Clermont-Ferrand University Hospital, G. Montpied Hospital, Clermont-Ferrand, France.,INRA, UMR 1019, Clermont-Ferrand, France
| | - Lore Metz
- EA 3533, Laboratory of the Metabolic Adaptations to Exercise Under Physiological and Pathological Conditions (AME2P), BP 80026, UE3533, Clermont Auvergne University, 63170, Aubiere CEDEX, France.,Auvergne Research Center for Human Nutrition (CRNH), 63000, Clermont-Ferrand, France
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Henning C, Stübner C, Arabi SH, Reichenwallner J, Hinderberger D, Fiedler R, Girndt M, Di Sanzo S, Ori A, Glomb MA. Glycation Alters the Fatty Acid Binding Capacity of Human Serum Albumin. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:3033-3046. [PMID: 35194998 DOI: 10.1021/acs.jafc.1c07218] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Glycation significantly alters the physicochemical and biofunctional properties of proteins in foods and in vivo. In the present study, human serum albumin (HSA) as the major transporter of fatty acids was modified with glyoxal under physiological conditions. Reversibly albumin-bound glyoxal was removed, and advanced glycation end products were quantitated by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The total modification of protein-bound lysine and arginine residues reached up to 4.2 and 9.6%, respectively. The impact of these modifications on the transport capacity of long-chain fatty acids was characterized by spin-labeled fatty acid probes via electron paramagnetic resonance spectroscopy. With increasing degree of glycation, the equivalence of the seven binding sites of native HSA with a dissociation constant of 0.74 ± 0.09 μM was set off with only the three high-affinity sites 2, 4, and 5 remaining (0.46 ± 0.07 μM). The other four sites were shifted to low affinities with significantly higher dissociation constants (1.32 ± 0.35 μM). Tryptic peptide mapping enabled us to relate these findings to molecular changes at specific binding sites. Modification hotspots identified were lysine 351, 286, 159 and arginine 144, 485, 117. Further investigation of plasma protein samples of uremic patients vs healthy controls gave first insights into the in vivo situation.
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Affiliation(s)
- Christian Henning
- Institute of Chemistry, Food Chemistry, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 2, 06120 Halle/Saale, Germany
| | - Christine Stübner
- Institute of Chemistry, Food Chemistry, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 2, 06120 Halle/Saale, Germany
| | - Seyed Hamidreza Arabi
- Institute of Chemistry, Physical Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle/Saale, Germany
| | - Jörg Reichenwallner
- Institute of Chemistry, Physical Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle/Saale, Germany
| | - Dariush Hinderberger
- Institute of Chemistry, Physical Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle/Saale, Germany
| | - Roman Fiedler
- Department of Internal Medicine II, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle/Saale, Germany
| | - Matthias Girndt
- Department of Internal Medicine II, Martin Luther University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle/Saale, Germany
| | - Simone Di Sanzo
- Leibniz Institute on Aging─Fritz Lipmann Institute, Beutenbergstr. 11, 07745 Jena, Germany
| | - Alessandro Ori
- Leibniz Institute on Aging─Fritz Lipmann Institute, Beutenbergstr. 11, 07745 Jena, Germany
| | - Marcus A Glomb
- Institute of Chemistry, Food Chemistry, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 2, 06120 Halle/Saale, Germany
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Similar rates of fat oxidation during graded submaximal exercise in women of different body composition. PLoS One 2020; 15:e0242551. [PMID: 33206727 PMCID: PMC7673546 DOI: 10.1371/journal.pone.0242551] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 11/04/2020] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Moderate intensity exercise ranging 40-60% of maximum oxygen uptake is advised to promote energy expenditure and fat oxidation in overweight and obese people. Although fat oxidation has been shown to be highly variable among individual, there is still a relative uncertainty regarding exercise prescription for women specifically. This article aimed to determine whether indicators of body composition can be used to narrow the exercise intensity range for exercise prescription in women. METHODS A total of 35 healthy women (age 30.8±9.5 yr) classified according to their BMI in normal weight (NOR; ≤24.9 kg·m2), overweight (OVW; 25-29.9 kg·m2) and obese groups (OBE; ≥30 kg·m2) completed a submaximal graded test (intensities eliciting ~30%, 40%, 50% and 60% of maximum oxygen uptake). Blood lactate, perceived exertion and absolute and relative substrate oxidation for fat (OXFAT) and carbohydrates (OXCHO) were measured at each stage. RESULTS Perceived exertion and blood lactate increased as a function of exercise but did not differ across groups. There were no significant changes in absolute and relative OXFAT across groups, or as a function of exercise intensity. Peak OXFAT occurred at the 40%, 50% and 40% stages for NOR, OVW and OBE groups, respectively, with no significant differences across groups. CONCLUSION We measured no differences, but considerable inter-individual variation, in fat oxidation in women of different body composition. This result is in agreement with previous research based on exercise performed at constant rate and in independent participant groups. Our findings do not support the fat oxidation hypothesis, and further emphasise the perspective that exercise prescription should be individualised and likely be based on considerations other than substrate oxidation.
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Delgado-Floody P, Izquierdo M, Ramírez-Vélez R, Caamaño-Navarrete F, Moris R, Jerez-Mayorga D, Andrade DC, Álvarez C. Effect of High-Intensity Interval Training on Body Composition, Cardiorespiratory Fitness, Blood Pressure, and Substrate Utilization During Exercise Among Prehypertensive and Hypertensive Patients With Excessive Adiposity. Front Physiol 2020; 11:558910. [PMID: 33192554 PMCID: PMC7604322 DOI: 10.3389/fphys.2020.558910] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 08/25/2020] [Indexed: 11/04/2022] Open
Abstract
Regular exercise training is a recognized lifestyle strategy to lower resting blood pressure (BP), but little is known about substrate metabolism in population with high BP. Thus, the purpose of this study was to investigate the effects of 16-weeks of HIIT on body composition, BP, cardiorespiratory fitness by V.O2max, and substrate utilization during exercise among prehypertensive and hypertensive patients with excessive adiposity. We also aimed to test the potential association between changes in cardiorespiratory fitness, substrate utilization during exercise and BP. Forty-two physically inactive overweight/obese participants participated in 16-weeks of HIIT intervention. The HIIT frequency was three times a week (work ratio 1:2:10, for interval cycling: rest period: repeated times; 80–100% of the maximum heart rate). Groups were distributed based on their baseline BP: HIIT-hypertensive (H-HTN: age 47.7 ± 12.0 years; body mass index [BMI] 30.3 ± 5.5 kg/m2; systolic [SBP]/diastolic BP [DBP] 151.6 ± 10/81.9 ± 4.2 mmHg), HIIT-pre-hypertensive (H-PreHTN: age 37.6 ± 12.0 years; BMI 31.9 ± 5.3 kg/m2; SBP/DBP 134.4 ± 3.2/74.9 ± 7.0 mmHg), and a normotensive control group (H-CG: age 40.7 ± 11.0 years; BMI 29.5 ± 4.2 kg/m2; SBP/DBP 117.0 ± 6.2/72.4 ± 4.1 mmHg). Anthropometry/body composition, BP, and metabolic substrate utilization during exercise (fat [FATox], carbohydrate [CHOox] oxidation, respiratory exchange ratio [RER], and V.O2max), were measured before and after the 16-week HIIT intervention. Adjusted mixed linear models revealed a significant improved in V.O2max were + 3.34 in the H-CG, + 3.63 in the H-PreHTN, and + 5.92 mL⋅kg–1⋅min–1, in the H-HTN group, however, the Time × Group interaction were not significant (p = 0.083). All the exercise types induced similar decreases on SBP (−8.70) in the H-HTN, (−7.14) in the H-CG, and (−5.11) mmHg in the H-PreHTN, as well as DBP levels (−5.43) mmHg in H-CG group (p = 0.032 vs. H-HTN group). At 16-week, no significant correlations were noted for the changes of blood pressure, cardiorespiratory fitness or exercise metabolism substrates outcomes. In conclusion, our results suggest that a 16-week HIIT-intervention improved V.O2max and blood pressure BP, but these changes are independent of substrate utilization during exercise in normotensive and hypertensive participants with excessive adiposity.
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Affiliation(s)
- Pedro Delgado-Floody
- Department of Physical Education, Sport and Recreation, Universidad de La Frontera, Temuco, Chile
| | - Mikel Izquierdo
- Navarrabiomed, Complejo Hospitalario de Navarra (CHN)-Universidad Pública de Navarra (UPNA), IdiSNA, Pamplona, Spain.,CIBER of Frailty and Healthy Aging (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain.,Grupo GICAEDS, Facultad de Cultura Física, Deporte y Recreación, Universidad Santo Tomás, Bogotá, Colombia
| | - Robinson Ramírez-Vélez
- Navarrabiomed, Complejo Hospitalario de Navarra (CHN)-Universidad Pública de Navarra (UPNA), IdiSNA, Pamplona, Spain.,CIBER of Frailty and Healthy Aging (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | | | - Roberto Moris
- Department of Physical Education, Sport and Recreation, Universidad de La Frontera, Temuco, Chile
| | | | - David C Andrade
- Centro de Investigación en Fisiología del Ejercicio, Universidad Mayor, Santiago, Chile
| | - Cristian Álvarez
- Quality of Life and Wellness Research Group, Department of Physical Activity Sciences, Universidad de Los Lagos, Osorno, Chile
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Arad AD, Basile AJ, Albu J, DiMenna FJ. No Influence of Overweight/Obesity on Exercise Lipid Oxidation: A Systematic Review. Int J Mol Sci 2020; 21:ijms21051614. [PMID: 32120832 PMCID: PMC7084725 DOI: 10.3390/ijms21051614] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/21/2020] [Accepted: 02/24/2020] [Indexed: 12/16/2022] Open
Abstract
Compared to lean counterparts, overweight/obese individuals rely less on lipid during fasting. This deficiency has been implicated in the association between overweight/obesity and blunted insulin signaling via elevated intramuscular triglycerides. However, the capacity for overweight/obese individuals to use lipid during exercise is unclear. This review was conducted to formulate a consensus regarding the influence of overweight/obesity on exercise lipid use. PubMed, ProQuest, ISI Web of Science, and Cochrane Library databases were searched. Articles were included if they presented original research on the influence of overweight/obesity on exercise fuel use in generally healthy sedentary adults. Articles were excluded if they assessed older adults, individuals with chronic disease, and/or exercise limitations or physically-active individuals. The search identified 1205 articles with 729 considered for inclusion after duplicate removal. Once titles, abstracts, and/or manuscripts were assessed, 24 articles were included. The preponderance of evidence from these articles indicates that overweight/obese individuals rely on lipid to a similar extent during exercise. However, conflicting findings were found in eight articles due to the outcome measure cited, participant characteristics other than overweight/obesity and characteristics of the exercise bout(s). We also identified factors other than body fatness which can influence exercise lipid oxidation that should be controlled in future research.
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Affiliation(s)
- Avigdor D. Arad
- Division of Endocrinology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (A.D.A.); (A.J.B.); (J.A.)
| | - Anthony J. Basile
- Division of Endocrinology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (A.D.A.); (A.J.B.); (J.A.)
| | - Jeanine Albu
- Division of Endocrinology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (A.D.A.); (A.J.B.); (J.A.)
| | - Fred J. DiMenna
- Division of Endocrinology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (A.D.A.); (A.J.B.); (J.A.)
- Department of Biobehavioral Sciences, Columbia University Teachers College, New York, NY 10027, USA
- Correspondence:
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Amaro-Gahete FJ, De-la-O A, Jurado-Fasoli L, Sanchez-Delgado G, Ruiz JR, Castillo MJ. Metabolic rate in sedentary adults, following different exercise training interventions: The FIT-AGEING randomized controlled trial. Clin Nutr 2020; 39:3230-3240. [PMID: 32089371 DOI: 10.1016/j.clnu.2020.02.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/06/2020] [Accepted: 02/01/2020] [Indexed: 01/08/2023]
Abstract
BACKGROUND & AIMS This study compares the influence of different exercise training programs on basal metabolic rate (BMR) and fat oxidation, in basal conditions (BFox) and during exercise (MFO), in sedentary, middle-aged adults. METHODS The study subjects of this 12 week-long, randomised controlled trial, were 71 middle-aged adults (age 53.5 ± 4.9 years; 52% women). Subjects were randomly assigned to one of the following groups: (1) no exercise, (2) concurrent training based on international physical activity recommendations (PAR group), (3) high intensity interval training (HIIT group), and (4) high intensity interval training plus whole-body electromyostimulation (HIIT + EMS group). Subject BMR, BFox and MFO were determined by indirect calorimetry before and after the intervention. RESULTS The HIIT + EMS subjects showed significant increases in BFox following the intervention compared with the control group (all P = 0.043); no such differences were seen in the PAR and HIIT compared with the control group (all P ≥ 0.1). A significant increase in post-intervention MFO was noted for the HIIT and HIIT + EMS group compared to the non-exercise control group (P < 0.05); no such difference was seen in the PAR group compared to the control group (all P ≥ 0.05). CONCLUSIONS Twelve weeks of high intensity interval training plus whole-body electromyostimulation may increase the BFox and MFO of middle-aged sedentary adults. These findings have important clinical implications; a well-designed high-intensity interval training program plus whole-body electromyostimulation might be followed to help combat the appearance of chronic metabolic diseases characterized by metabolic inflexibility in middle-aged sedentary adults, though it will be necessary to determine how long the effects last.
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Affiliation(s)
- Francisco J Amaro-Gahete
- EFFECTS-262 Research Group, Department of Medical Physiology, School of Medicine, University of Granada, Spain; PROmoting FITness and Health Through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Spain.
| | - Alejandro De-la-O
- EFFECTS-262 Research Group, Department of Medical Physiology, School of Medicine, University of Granada, Spain
| | - Lucas Jurado-Fasoli
- EFFECTS-262 Research Group, Department of Medical Physiology, School of Medicine, University of Granada, Spain
| | - Guillermo Sanchez-Delgado
- PROmoting FITness and Health Through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Spain; Pennington Biomedical Research Center, LA USA
| | - Jonatan R Ruiz
- PROmoting FITness and Health Through Physical Activity Research Group (PROFITH), Sport and Health University Research Institute (iMUDS), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Spain
| | - Manuel J Castillo
- EFFECTS-262 Research Group, Department of Medical Physiology, School of Medicine, University of Granada, Spain
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DiMenna FJ, Arad AD. Exercise as 'precision medicine' for insulin resistance and its progression to type 2 diabetes: a research review. BMC Sports Sci Med Rehabil 2018; 10:21. [PMID: 30479775 PMCID: PMC6251139 DOI: 10.1186/s13102-018-0110-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 11/13/2018] [Indexed: 02/08/2023]
Abstract
Type 2 diabetes and obesity epidemics are in effect in the United States and the two pathologies are linked. In accordance with the growing appreciation that ‘exercise is medicine,’ it is intuitive to suggest that exercise can play an important role in the prevention and/or treatment of these conditions. However, if exercise is to truly be considered as a viable alternative to conventional healthcare prevention/treatment strategies involving pharmaceuticals, it must be prescribed with similar scrutiny. Indeed, it seems reasonable to posit that the recent initiative calling for ‘precision medicine’ in the US standard healthcare system should also be applied in the exercise setting. In this narrative review, we consider a number of explanations that have been forwarded regarding the pathological progression to type 2 diabetes both with and without the concurrent influence of overweight/obesity. Our goal is to provide insight regarding exercise strategies that might be useful as ‘precision medicine’ to prevent/treat this disease. Although the etiology of type 2 diabetes is complex and cause/consequence characteristics of associated dysfunctions have been debated, it is well established that impaired insulin action plays a critical early role. Consequently, an exercise strategy to prevent/treat this disease should be geared toward improving insulin sensitivity both from an acute and chronic standpoint. However, research suggests that a chronic improvement in insulin sensitivity only manifests when weight loss accompanies an exercise intervention. This has resonance because ectopic fat accumulation appears to represent a central component of disease progression regardless of whether obesity is also part of the equation. The cause/consequence characteristics of the relationship between insulin resistance, pathological fat deposition and/or mobilsation, elevated and/or poorly-distributed lipid within myocytes and an impaired capacity to use lipid as fuel remains to be clarified as does the role of muscle mitochondria in the metabolic decline. Until these issues are resolved, a multidimensional exercise strategy (e.g., aerobic exercise at a range of intensities and resistance training for muscular hypertrophy) could provide the best alternative for prevention/treatment.
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Affiliation(s)
- Fred J DiMenna
- 1Division of Endocrinology, Diabetes and Bone Disease, Icahn School of Medicine at Mount Sinai, 1111 Amsterdam Avenue, Babcock 10th Floor, Suite 1020, New York, 10025 New York USA.,2Department of Biobehavioral Sciences, Columbia University Teachers College, 525 W. 120th Street, New York, 10027 New York USA
| | - Avigdor D Arad
- 1Division of Endocrinology, Diabetes and Bone Disease, Icahn School of Medicine at Mount Sinai, 1111 Amsterdam Avenue, Babcock 10th Floor, Suite 1020, New York, 10025 New York USA
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Grenier-Larouche T, Carreau AM, Geloën A, Frisch F, Biertho L, Marceau S, Lebel S, Hould FS, Richard D, Tchernof A, Carpentier AC. Fatty Acid Metabolic Remodeling During Type 2 Diabetes Remission After Bariatric Surgery. Diabetes 2017; 66:2743-2755. [PMID: 28835473 DOI: 10.2337/db17-0414] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 08/10/2017] [Indexed: 11/13/2022]
Abstract
Hypertrophic remodeling of white adipose tissues is associated with overexposure of lean organs to circulating triglycerides (TGs) and nonesterified fatty acids (NEFAs), ultimately leading to insulin resistance. Bariatric surgery promotes type 2 diabetes (T2D) remission through a succession of weight loss-dependent and -independent mechanisms. However, the longitudinal contribution of adipocyte size reduction and fatty acid metabolic handling remain unknown. Here we show that severely obese participants with T2D display hypertriglyceridemia and excessive systemic lipolysis during intravenous lipid overload. Three days after biliopancreatic diversion with duodenal switch (DS), whole-body glycerol turnover was normalized and associated with lower HOMA-insulin resistance index. A mean excess weight loss of 84% was achieved 12 months after DS. The smaller subcutaneous adipocyte size predicted better glycemic control in T2D. TG disposal and acylcarnitine production during lipid overload, along with muscle insulin sensitivity, improved with weight loss. Nevertheless, systemic NEFA fluxes and NEFA spillover remained similar, suggesting that increased NEFA storage capacity per volume of adipose tissue exactly compensated for the decrease in fat mass during weight loss. In conclusion, T2D remission after DS is mainly associated with greater circulating TG disposal, lower systemic lipolysis, and better fatty acid handling by lean tissues.
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Affiliation(s)
- Thomas Grenier-Larouche
- Department of Medicine, Division of Endocrinology, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Québec, Canada
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Anne-Marie Carreau
- Department of Medicine, Division of Endocrinology, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Alain Geloën
- University of Lyon, CARMEN INSERM U1060, INSA-Lyon, Villeurbanne, France
| | - Frédérique Frisch
- Department of Medicine, Division of Endocrinology, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Laurent Biertho
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Simon Marceau
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Stéfane Lebel
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Frédéric-Simon Hould
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Denis Richard
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - André Tchernof
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - André C Carpentier
- Department of Medicine, Division of Endocrinology, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Québec, Canada
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Isacco L, Thivel D, Duclos M, Aucouturier J, Boisseau N. Discussion of “Body Fat Has No Effect on the Maximal Fat Oxidation Rate in Young Normal and Overweight Women”. J Strength Cond Res 2016. [DOI: 10.1519/jsc.0000000000000742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Malin SK, Liu Z, Barrett EJ, Weltman A. Exercise resistance across the prediabetes phenotypes: Impact on insulin sensitivity and substrate metabolism. Rev Endocr Metab Disord 2016; 17:81-90. [PMID: 27106830 DOI: 10.1007/s11154-016-9352-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Prediabetes is a heterogeneous term that encompasses different origins of insulin resistance and insulin secretion that contribute to distinct patterns of hyperglycemia. In fact, prediabetes is an umbrella term that characterizes individuals at high risk for developing type 2 diabetes (T2D) and/or cardiovascular disease (CVD). Based on current definitions there are at least 3 distinct phenotypes of prediabetes: impaired fasting glucose (IFG), impaired glucose tolerant (IGT), or the combination of both (IFG + IGT). Each phenotype is clinically relevant as they are uniquely recognized as having different levels of risk for progressing to T2D and CVD. Herein, we discuss the underlying pathophysiology that characterizes IFG, IGT and the combination, as well as examine how some of these phenotypes appear resistant to traditional exercise interventions. We propose that substrate metabolism differences between the prediabetes phenotypes may be a unifying mechanism that explains the inter-subject variation in response to exercise seen across obese, metabolic syndrome, pre-diabetic and T2D patients in the current literature. Ultimately, a better understanding of the pathophysiologic mechanisms that govern disturbances responsible for fasting vs. postprandial hyperglycemia and the combination of both is important for designing optimal and personalized exercise treatment strategies that treat and prevent hyperglycemia and CVD risk.
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Affiliation(s)
- Steven K Malin
- Applied Metabolism & Physiology Laboratory, Department of Kinesiology, University of Virginia, 210 Emmet St., 225A Memorial Gymnasium, Charlottesville, VA, USA.
- Division of Endocrinology and Metabolism, University of Virginia, Charlottesville, VA, USA.
| | - Zhenqi Liu
- Division of Endocrinology and Metabolism, University of Virginia, Charlottesville, VA, USA
| | - Eugene J Barrett
- Division of Endocrinology and Metabolism, University of Virginia, Charlottesville, VA, USA
| | - Arthur Weltman
- Applied Metabolism & Physiology Laboratory, Department of Kinesiology, University of Virginia, 210 Emmet St., 225A Memorial Gymnasium, Charlottesville, VA, USA
- Division of Endocrinology and Metabolism, University of Virginia, Charlottesville, VA, USA
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Slusher AL, Whitehurst M, Zoeller RF, Mock JT, Maharaj M, Huang CJ. Attenuated fibroblast growth factor 21 response to acute aerobic exercise in obese individuals. Nutr Metab Cardiovasc Dis 2015; 25:839-845. [PMID: 26141939 DOI: 10.1016/j.numecd.2015.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 05/19/2015] [Accepted: 06/01/2015] [Indexed: 01/13/2023]
Abstract
BACKGROUND AND AIM Fibroblast growth factor 21 (FGF21) is positively associated with body mass index, potentially as a compensatory mechanism to mediate obesity related metabolic and inflammatory insult due to chronic low-grade elevations of the pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α). Therefore, FGF21 response in obese subjects and the associations with increased pro-inflammatory cytokines, insulin resistance, and energy utilization warrants investigation. METHODS AND RESULTS Twenty four untrained subjects (12 obese and 12 normal-weight) performed 30 min of continuous submaximal aerobic exercise. Following exercise, obese subjects exhibited a blunted FGF21 response to exercise compared to normal-weight subjects as indicated by area-under-the-curves "with respect to increase" (AUCi) analyses (p = 0.005). Furthermore, while exercise-induced plasma FGF21 was not associated with any inflammatory cytokine (IL-6 and TNF-α) response, FGF21 AUCi was positively correlated with glucose AUCi (r = 0.495, p = 0.014), total relative energy expenditure (r = 0.562, p = 0.004), and relative maximal oxygen consumption (VO2max; r = 0.646, p = 0.001) in all subjects. CONCLUSION Impaired cardiorespiratory fitness may influence the sensitivity of FGF21 response to acute exercise in obese individuals, potentially contributing to the attenuated metabolic response (e.g., glucose) and total exercise energy expenditure. Therefore, exercise training aimed at improving cardiorespiratory fitness and/or body composition may augment cardioprotective properties against obesity-associated CVD through enhanced FGF21 flux.
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Affiliation(s)
- A L Slusher
- Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA; Department of Kinesiology and Health Sciences, Virginia Commonwealth University, VA, USA.
| | - M Whitehurst
- Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA
| | - R F Zoeller
- Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA
| | - J T Mock
- Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA
| | - M Maharaj
- Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA
| | - C-J Huang
- Exercise Biochemistry Laboratory, Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, USA
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Effects of weight loss via high fat vs. low fat alternate day fasting diets on free fatty acid profiles. Sci Rep 2015; 5:7561. [PMID: 25557754 PMCID: PMC5378987 DOI: 10.1038/srep07561] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 11/26/2014] [Indexed: 01/09/2023] Open
Abstract
Cardiovascular disease risk is associated with excess body weight and elevated plasma free fatty acid (FFA) concentrations. This study examines how an alternate-day fasting (ADF) diet high (HF) or low (LF) in fat affects plasma FFA profiles in the context of weight loss, and changes in body composition and lipid profiles. After a 2-week weight maintenance period, 29 women (BMI 30-39.9 kg/m(2)) 25-65 years old were randomized to an 8-week ADF-HF (45% fat) diet or an ADF-LF (25% fat) diet with 25% energy intake on fast days and ad libitum intake on feed days. Body weight, BMI and waist circumference were assessed weekly and body composition was measured using dual x-ray absorptiometry (DXA). Total and individual FFA and plasma lipid concentrations were measured before and after weight loss. Body weight, BMI, fat mass, total cholesterol, LDL-C and triglyceride concentrations decreased (P < 0.05) in both groups. Total FFA concentrations also decreased (P < 0.001). In the ADF-LF group, decreases were found in several more FFAs than in the ADF-HF group. In the ADF-HF group, FFA concentrations were positively correlated with waist circumference. Depending on the macronutrient composition of a diet, weight loss with an ADF diet decreases FFA concentrations through potentially different mechanisms.
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Isacco L, Duche P, Thivel D, Meddahi-Pelle A, Lemoine-Morel S, Duclos M, Boisseau N. Fat mass localization alters fuel oxidation during exercise in normal weight women. Med Sci Sports Exerc 2014; 45:1887-96. [PMID: 23531714 DOI: 10.1249/mss.0b013e3182935fe3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Abdominal and lower body fat mass tissues exhibit particular metabolic profiles at rest and during exercise. However, data are missing in normal weight women during exercise. The purpose of this study was to investigate the effect of low (LA/LB) and high (HA/LB) abdominal to lower body (A/LB) fat mass ratio on metabolic and hormonal responses during exercise in premenopausal normal weight women. METHODS After preliminary testing (V˙O2max and body composition assessment), substrate oxidation (RER, lipid, and carbohydrate oxidation rates), metabolic response (glycerol, free fatty acids, and glucose), and hormonal response (insulin, growth hormone, atrial natriuretic peptide, adrenaline, and noradrenaline) were determined during exercise (45 min at 65% of V˙O2max) in 21 premenopausal normal weight women (10 HA/LB women vs 11 LA/LB women). RESULTS Waist circumference was significantly higher in HA/LB women compared with LA/LB women (P < 0.01). No difference in other anthropometric characteristics, V˙O2max, and resting blood values was observed between the two groups. LA/LB subjects exhibited greater lipid oxidation rates compared with HA/LB women during exercise (P < 0.01). This occurred with lower plasma insulin (P < 0.05) and glucose (P < 0.05) concentrations and higher plasma free fatty acids (P < 0.05), glycerol (P < 0.05), growth hormone (P < 0.05), and atrial natriuretic peptide levels (P < 0.01) during exercise in the LA/LB group compared with the HA/LB group. CONCLUSIONS The present study demonstrated that LA/LB women exhibited an increase in whole-body lipid mobilization and use during exercise compared with HA/LB counterparts. This greater reliance on lipid as fuel metabolism during exercise could be explained by substrate availability and metabolic and hormonal responses. It appeared that LA/LB women exhibited greater metabolic flexibility during an exercise bout of 45 min at 65% of V˙O2max on cycle ergometer.
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Affiliation(s)
- Laurie Isacco
- 1Laboratory of Metabolic Adaptations to Exercise in Physiological and Pathological Conditions, Blaise Pascal University, Clermont-Ferrand, FRANCE; 2INSERM U698, Bioengineering for Cardiovascular Imaging and Therapy, Paris, FRANCE; 3Paris University 13, IUT of Saint-Denis, FRANCE; 4Laboratory Movement Sport and Health Sciences, EA 1274, UFR APS, University of Rennes 2, Rennes Cedex, FRANCE; 5Department of Sport Medicine and Functional Explorations, Clermont-Ferrand University Hospital, G. Montpied Hospital, Clermont-Ferrand, FRANCE; 6INRA, UMR 1019, Clermont-Ferrand, FRANCE; 7University Clermont 1, UFR Medicine, Clermont-Ferrand, FRANCE; and 8CRNH-Auvergne, Clermont-Ferrand, FRANCE
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Isacco L, Thivel D, Duclos M, Aucouturier J, Boisseau N. Effects of adipose tissue distribution on maximum lipid oxidation rate during exercise in normal-weight women. DIABETES & METABOLISM 2014; 40:215-9. [PMID: 24698815 DOI: 10.1016/j.diabet.2014.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 02/26/2014] [Accepted: 02/27/2014] [Indexed: 12/24/2022]
Abstract
AIM Fat mass localization affects lipid metabolism differently at rest and during exercise in overweight and normal-weight subjects. The aim of this study was to investigate the impact of a low vs high ratio of abdominal to lower-body fat mass (index of adipose tissue distribution) on the exercise intensity (Lipox(max)) that elicits the maximum lipid oxidation rate in normal-weight women. METHODS Twenty-one normal-weight women (22.0 ± 0.6 years, 22.3 ± 0.1 kg.m(-2)) were separated into two groups of either a low or high abdominal to lower-body fat mass ratio [L-A/LB (n = 11) or H-A/LB (n = 10), respectively]. Lipox(max) and maximum lipid oxidation rate (MLOR) were determined during a submaximum incremental exercise test. Abdominal and lower-body fat mass were determined from DXA scans. RESULTS The two groups did not differ in aerobic fitness, total fat mass, or total and localized fat-free mass. Lipox(max) and MLOR were significantly lower in H-A/LB vs L-A/LB women (43 ± 3% VO(2max) vs 54 ± 4% VO(2max), and 4.8 ± 0.6 mg min(-1)kg FFM(-1)vs 8.4 ± 0.9 mg min(-1)kg FFM(-1), respectively; P < 0.001). Total and abdominal fat mass measurements were negatively associated with Lipox(max) (r = -0.57 and r = -0.64, respectively; P < 0.01) and MLOR [r = -0.63 (P < 0.01) and r = -0.76 (P < 0.001), respectively]. CONCLUSION These findings indicate that, in normal-weight women, a predominantly abdominal fat mass distribution compared with a predominantly peripheral fat mass distribution is associated with a lower capacity to maximize lipid oxidation during exercise, as evidenced by their lower Lipox(max) and MLOR.
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Affiliation(s)
- L Isacco
- Laboratory Culture Sport Health Society, EA 4660, and Exercise Performance, Health, Innovation Platform, Franche-Comte University, 25000 Besançon, France.
| | - D Thivel
- EA 3533, Laboratory of Metabolic Adaptations to Exercise in Physiological and Pathological Conditions, Clermont University, Blaise Pascal University, BP 10448, 63000 Clermont-Ferrand, France.
| | - M Duclos
- Department of Sport Medicine and Functional Explorations, Clermont-Ferrand University Hospital (CHU), G. Montpied Hospital, 63003 Clermont-Ferrand, France; INRA, UMR 1019, 63001 Clermont-Ferrand, France; University Clermont 1, UFR Medicine, 63001 Clermont-Ferrand, France; CRNH-Auvergne, 63001 Clermont-Ferrand, France.
| | - J Aucouturier
- EA4488, Lille Nord de France University, "Physical Activity, muscle, Health", 59790 Ronchin, France.
| | - N Boisseau
- EA 3533, Laboratory of Metabolic Adaptations to Exercise in Physiological and Pathological Conditions, Clermont University, Blaise Pascal University, BP 10448, 63000 Clermont-Ferrand, France.
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Malin SK, Viskochil R, Oliver C, Braun B. Mild fasting hyperglycemia shifts fuel reliance toward fat during exercise in adults with impaired glucose tolerance. J Appl Physiol (1985) 2013; 115:78-83. [PMID: 23599396 DOI: 10.1152/japplphysiol.00084.2013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Impaired glucose tolerance (IGT) is characterized by decreased oxidative capacity and reduced carbohydrate utilization during exercise. However, it is unclear if the presence of impaired fasting glucose (IFG) affects fuel utilization during exercise in adults with IGT. We tested the hypothesis that the presence of IFG in adults with IGT decreases reliance on carbohydrate during exercise. Middle-aged, obese, sedentary individuals (n = 6, IGT and n = 6, IFG+IGT) were compared during exercise at 60% peak O2 consumption for 45 min on a cycle ergometer. Glucose rates of appearance and disposal and muscle glycogen were assessed by stable isotope dilution methods, and fat utilization was estimated via indirect calorimetry. A 75-g oral glucose tolerance test was used to determine fasting and 2-h glucose concentrations. A glucose intolerance severity z-score was calculated from the oral glucose tolerance test. Glucose flux (i.e., rates of appearance and disposal) was not different between groups. However, individuals with IFG+IGT had lower muscle glycogen use (P < 0.05) and elevated fat oxidation (P < 0.01) during exercise compared with those with isolated IGT. Plasma nonesterified fatty acids and glucose were significantly higher during exercise in subjects with IFG+IGT vs. IGT alone (P < 0.05). Fat utilization during exercise correlated with fasting glucose (r = 0.57, P = 0.05), glucose intolerance severity z-score (r = 0.66, P = 0.01), and nonesterified fatty acids (trend; r = 0.55, P = 0.08). The presence of IFG shifts fuel selection toward increased fat oxidation and decreased muscle glycogen utilization during exercise in adults with IGT. Whether these differences in substrate use contribute to, or are the result of, movement along the continuum from prediabetes to type 2 diabetes awaits further work.
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Affiliation(s)
- Steven K Malin
- Energy Metabolism Laboratory, Department of Kinesiology, University of Massachusetts, Amherst, MA 01003, USA
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Mensink M, Blaak EE, Wagenmakers AJ, Saris WH. Lifestyle Intervention and Fatty Acid Metabolism in Glucose-Intolerant Subjects. ACTA ACUST UNITED AC 2012; 13:1354-62. [PMID: 16129717 DOI: 10.1038/oby.2005.164] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Free fatty acid (FFA) oxidation is reduced in subjects with type 2 diabetes mellitus and impaired glucose tolerance (IGT). Weight reduction does not improve these impairments. Because exercise training is known to increase fatty acid (FA) oxidation, we investigated whether a combined diet and physical activity intervention program can improve FA oxidation in subjects with IGT. RESEARCH METHODS AND PROCEDURES Sixteen subjects with IGT were studied before and after 1 year of a lifestyle intervention program [nine intervention (INT) subjects, seven controls (CON)]. INT subjects received regular (i.e., every 3 months) dietary advice and were stimulated to increase their level of physical activity. Glucose tolerance, anthropometric characteristics, and substrate use at rest and during exercise were evaluated before and after 1 year. Substrate oxidation was measured at rest and during moderate intensity exercise using indirect calorimetry in combination with stable isotope infusion ([U-(13)C]palmitate and [6,6-(2)H(2)-]glucose). RESULTS After 1 year, no differences were seen in substrate use at rest. During exercise, total fat and plasma FFA oxidation were slightly increased in the INT group and decreased in the CON group, with the change being significantly different (change after 1 year: INT, +2.0 +/- 1.4 and +1.9 +/- 0.9 micromol/kg per minute; CON, -3.5 +/- 1.6 and -1.8 +/- 0.5 micromol/kg per minute for total and plasma FFA, respectively; p < 0.05). DISCUSSION A combined diet and physical activity intervention program can prevent further deterioration of impaired FA oxidation during exercise in subjects with IGT.
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Affiliation(s)
- Marco Mensink
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, The Netherlands.
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Nellemann B, Gormsen LC, Sørensen LP, Christiansen JS, Nielsen S. Impaired insulin-mediated antilipolysis and lactate release in adipose tissue of upper-body obese women. Obesity (Silver Spring) 2012; 20:57-64. [PMID: 21959346 DOI: 10.1038/oby.2011.290] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Upper-body/visceral obesity is associated with abnormalities of free fatty acid (FFA) metabolism and greater risk of developing type 2 diabetes compared with lower-body obesity. In lean subjects lipolysis is readily suppressed by insulin; however, metabolic inflexibility with respect to antilipolysis is a frequent finding in obesity, partly determined by body composition. This study investigates effects of insulin on regional adipose tissue lipolysis and lactate levels in upper-body overweight/obese (UBO), lower-body overweight/obese (LBO), and lean women. The microdialysis technique was used to assess adipose tissue glycerol and lactate concentrations in abdominal and femoral fat during a 5-h basal period and a 2-h hyperinsulinemic euglycemic clamp. The main findings were that the antilipolytic effect of insulin was attenuated in abdominal fat of UBO (glycerol reduction, abd (%): UBO 40.4 (-14 to 66), LBO 46.0 (-8 to 66), lean 66.2 (2-78), ANOVA, P < 0.05), and in femoral fat in both obese groups (glycerol reduction, fem (%): UBO 44.4 (35-67), LBO 44.4 (0-63), lean 65.0 (43-79), ANOVA, P < 0.05). Further, abdominal fat insulin-mediated increase in lactate concentration was greater in lean women compared with UBO women (lactate increase, abd (%): UBO -6.1 (-37.1 to 57.4), LBO 16.5 (-32.2 to 112.5), lean 51.4 (-45.7 to 162.9), P < 0.05), whereas no differences were found between groups in femoral fat (lactate increase, fem (%), UBO -12.9 (-43 to 24), LBO 12.7 (-30.7 to 92), lean 27.6 (-9.5 to 123.8), not significant). Respiratory exchange ratio (RER) increased significantly and similarly in all groups. So, UBO women were metabolically inflexible with respect to insulins antilipolytic and lactate increasing effects in abdominal adipose tissue. These phenomena are probably both consequences of insulin resistance of adipose tissue.
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Affiliation(s)
- Birgitte Nellemann
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
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Balcı SS. Comparison of substrate oxidation during walking and running in normal-weight and overweight/obese men. Obes Facts 2012; 5:327-38. [PMID: 22722096 DOI: 10.1159/000339504] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 11/15/2011] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE The aim of the present study is to examine the differences in fat and carbohydrate (CHO) oxidation during walking and running between normal-weight and overweight/obese young adult men. METHODS 19 healthy, normal-weight (age = 21.9 ± 0.7 years, BMI = 22.6 ± 0.4 kg, n = 10) and overweight (age = 21.4 ± 0.6 years, BMI = 31.6 ± 1.1, n = 9) young men volunteered to participate in this study. Body composition was assessed by bioelectrical impedance. Maximal oxygen uptake and maximal fat oxidation rate were determined with indirect calorimetry by using an incremental exercise test on a motor-driven treadmill. The participants' individual preferred transition speeds between walking and running were determined. Indirect calorimetry was used to calculate fat and CHO oxidation during the resting, walking and running tests. RESULTS Maximal fat oxidation rates during the graded exercise test were not significantly different between the groups. Changes in CHO and fat oxidation in the resting, walking and running tests were similar in the normal-weight and overweight groups. CONCLUSION The study results suggest that with regard to changes in CHO and fat oxidation, normal-weight and overweight/obese individuals have similar responses to walking and running at preferred speeds, despite significant differences in oxygen uptake during activity and body composition.
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Affiliation(s)
- Sükrü Serdar Balcı
- School of Physical Education and Sport, Selçuk University, Alleaddin Keykubat Campus, Selçuklu/Konya, Turkey.
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Numao S, Katayama Y, Hayashi Y, Matsuo T, Tanaka K. Influence of acute aerobic exercise on adiponectin oligomer concentrations in middle-aged abdominally obese men. Metabolism 2011; 60:186-94. [PMID: 20102772 DOI: 10.1016/j.metabol.2009.12.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 11/13/2009] [Accepted: 12/09/2009] [Indexed: 11/28/2022]
Abstract
Exercise intensity may induce changes in total adiponectin and adiponectin oligomer levels. However, the effects of acute aerobic exercise on total adiponectin and adiponectin oligomers in middle-aged abdominally obese men remain unknown. The purpose of this study was to investigate the influence of aerobic exercise intensity on changes in the concentrations of total adiponectin and adiponectin oligomers (high-molecular weight [HMW] and middle- plus low-molecular weight [MLMW] adiponectin), and the endocrine mechanisms involved in exercise-induced changes in adiponectin oligomer profiles in middle-aged abdominally obese men. Using a crossover design, 9 middle-aged abdominally obese men (age, 54.1 ± 2.4 years; body mass index, 27.9 ± 0.6 kg/m²) underwent 2 trials that consisted of 60 minutes of stationary cycle exercise at either moderate-intensity (ME) or high-intensity (HE) aerobic exercise (50% or 70% of peak oxygen uptake, respectively). Blood samples were collected to measure the concentrations of adiponectin oligomers, hormones (catecholamines, insulin, and growth hormone), metabolites (free fatty acid, glycerol, triglyceride, and glucose), and cytokines (interleukin-6 and tumor necrosis factor-α). After exercise, plasma catecholamine concentrations were higher during HE than during ME (P < .05). Total adiponectin concentration decreased at the end of HE (P < .05), but remained unchanged after ME. The HMW adiponectin concentration did not change at either intensity, whereas the MLMW concentration decreased at the end of HE (P < .05). The ratio of HMW to total adiponectin concentration increased significantly (P < .05), whereas the ratio of MLMW to total adiponectin concentration decreased significantly (P < .05), at the end of HE. The percentage changes in epinephrine concentration from baseline to the end of exercise were correlated with the percentage changes in total adiponectin concentration (r = -0.67, P < .05) and MLMW adiponectin concentration (r = -0.82, P < .05) from baseline to the end of HE. Our results indicate that the change in total adiponectin was mainly due to a change in MLMW adiponectin concentration during high-intensity exercise in middle-aged abdominally obese men. Epinephrine may partially regulate the decrease in total and MLMW adiponectin concentrations during high-intensity exercise.
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Affiliation(s)
- Shigeharu Numao
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama 359-1192, Japan.
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Wasserman DH, Cherrington AD. Regulation of Extramuscular Fuel Sources During Exercise. Compr Physiol 2011. [DOI: 10.1002/cphy.cp120123] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Nellemann B, Gormsen LC, Christiansen JS, Jensen MD, Nielsen S. Postabsorptive VLDL-TG fatty acid storage in adipose tissue in lean and obese women. Obesity (Silver Spring) 2010; 18:1304-11. [PMID: 19875996 PMCID: PMC2893248 DOI: 10.1038/oby.2009.370] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Adipose tissue lipoprotein lipase (LPL) is a necessary enzyme for storage of very-low-density lipoprotein-triglyceride (VLDL-TG), but whether it is a rate-determining step is unknown. To test this hypothesis we included 10 upper-body obese (UBO), 11 lower-body obese (LBO), and 8 lean women. We infused ex vivo-labeled VLDL-(14)C-TG and then performed adipose tissue biopsies to understand the relationship between VLDL-TG storage and LPL activity in femoral and upper-body subcutaneous fat. Both fractional tracer storage and rate of storage of the VLDL-TG tracer were evaluated. VLDL-TG storage was also examined as a function of regional adipose tissue blood flow (ATBF), insulin, VLDL-TG turnover, regional fat mass, fat-free mass (FFM), and fat cell size. LPL activity per adipocyte was significantly greater in obese than lean women but not significantly different per gram lipid. Both VLDL-TG fractional tracer storage per kg lipid and VLDL-TG storage rate per kg lipid were similar in abdominal and femoral fat in all three groups and were not significantly different between groups. Multiple regression analysis identified FFM and femoral fat mass as significant independent predictors of VLDL-TG fractional tracer storage and insulin as a significant predictor of VLDL-TG fatty acid storage rate. LPL activity, ATBF, and VLDL-TG turnover did not predict VLDL-TG storage. We conclude that lower FFM and greater plasma insulin are associated with greater VLDL-TG deposition in abdominal subcutaneous and femoral fat. Greater femoral fat mass signals greater femoral VLDL-TG storage. We suggest that the differences in VLDL-TG storage in abdominal and femoral fat that occur with progressive obesity are regulated through mechanisms other than LPL activity.
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Schenk S, Harber MP, Shrivastava CR, Burant CF, Horowitz JF. Improved insulin sensitivity after weight loss and exercise training is mediated by a reduction in plasma fatty acid mobilization, not enhanced oxidative capacity. J Physiol 2009; 587:4949-61. [PMID: 19723783 PMCID: PMC2770158 DOI: 10.1113/jphysiol.2009.175489] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 08/24/2009] [Indexed: 12/22/2022] Open
Abstract
Obesity is characterized by excessive rates of plasma fatty acid mobilization and uptake, which play a key role in mediating insulin resistance. While weight loss via diet-only or a diet + exercise program clearly improves insulin sensitivity, the precise mechanisms modulating this improvement are not completely understood. The purpose of the present study was to determine the role of the reduced fatty acid mobilization and uptake after weight loss in obese women who were randomly assigned to lifestyle interventions of either weight loss without exercise (WL) (n = 7) or a weight loss + exercise program (WL + EX) (n = 10). Before and after losing 12% of their body weight, we measured insulin sensitivity (S(I)), systemic fatty acid rate of appearance (Ra) and disappearance (Rd), oxidative capacity, and markers for pro-inflammatory pathways in skeletal muscle. Fatty acid Ra and Rd were reduced by 30% after both interventions (P < 0.05). While oxidative capacity increased 25% in WL + EX (compared with no increase after WL), the improvement in S(I) was identical in both groups (60%; P < 0.05), and skeletal muscle pro-inflammatory pathways were reduced (P < 0.05) similarly in both groups. When we artificially increased fatty acid mobilization after weight loss to pre-weight-loss levels via an overnight lipid infusion, the improvement in S(I) was almost completely reversed. Importantly, WL + EX did not protect against this lipid-induced reversal in S(I) despite a significant increase in resting whole-body fat oxidation and a marked increase in skeletal muscle oxidative capacity. In conclusion, reduced fatty acid mobilization and uptake appears to be a primary mediator of improved insulin sensitivity after weight loss. Moreover, enhancing fatty acid oxidative capacity via exercise training is not sufficient to prevent the insulin resistance caused by high fatty acid mobilization, such as that found in obesity.
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Affiliation(s)
- Simon Schenk
- School of Kinesiology, The University of Michigan, Ann Arbor, MI 48109-2214, USA
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Mittendorfer B, Magkos F, Fabbrini E, Mohammed BS, Klein S. Relationship between body fat mass and free fatty acid kinetics in men and women. Obesity (Silver Spring) 2009; 17:1872-7. [PMID: 19629053 PMCID: PMC3319738 DOI: 10.1038/oby.2009.224] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
An increased release of free fatty acids (FFAs) into plasma likely contributes to the metabolic complications associated with obesity. However, the relationship between body fat and FFA metabolism is unclear because of conflicting results from different studies. The goal of our study was to determine the inter-relationships between body fat, sex, and plasma FFA kinetics. We determined FFA rate of appearance (Ra) in plasma, by using stable isotopically labeled tracer techniques, during basal conditions in 106 lean, overweight, and obese, nondiabetic subjects (43 men and 63 women who had 7.0-56.0% body fat). Correlation analyses demonstrated: (i) no differences between men and women in the relationship between fat mass (FM) and total FFA Ra (micromol/min); (ii) total FFA Ra increased linearly with increasing FM (r=0.652, P<0.001); (iii) FFA Ra per kg FM decreased in a curvilinear fashion with increasing FM (r=-0.806; P<0.001); (iv) FFA Ra in relationship to fat-free mass (FFM) was greater in obese than lean subjects and greater in women than in men; and (v) abdominal fat itself was not an important determinant of total FFA Ra. We conclude that total body fat, not regional fat distribution or sex, is an important modulator of the rate of FFA release into plasma. Although increased adiposity is associated with a decrease in fatty acid release in relationship to FM, this downregulation is unable to completely compensate for the increase in FM, so total FFA Ra and FFA Ra with respect to FFM are greater in women than in men and in obese than in lean subjects.
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Affiliation(s)
- Bettina Mittendorfer
- Division of Geriatrics and Nutritional Science and Center for Human Nutrition, Washington University School of Medicine, St Louis, Missouri, USA.
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Numao S, Hayashi Y, Katayama Y, Matsuo T, Tanaka K. Sex differences in substrate oxidation during aerobic exercise in obese men and postmenopausal obese women. Metabolism 2009; 58:1312-9. [PMID: 19501865 DOI: 10.1016/j.metabol.2009.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 04/20/2009] [Accepted: 04/21/2009] [Indexed: 01/25/2023]
Abstract
The aim of this study was to compare substrate oxidation during aerobic exercise in obese men and postmenopausal obese women. Ten obese men (mean age, 55.4 +/- 2.2 years; body mass index, 27.5 +/- 0.4 kg/m(2); peak oxygen uptake [Vo(2)peak], 44.4 +/- 1.9 mL/kg fat-free mass/min; mean +/- SE] and 10 postmenopausal obese women (mean age, 57.2 +/- 1.2 years; body mass index, 27.9 +/- 0.5 kg/m(2); VO(2)peak, 39.9 +/- 1.3 mL/kg fat-free mass/min) performed a 40-minute bout of cycling exercise at 50% VO(2)peak. Blood samples were collected for assessment of metabolic variables and 17beta-estradiol concentration at baseline and during aerobic exercise. Breath samples were collected to estimate carbohydrate and fat oxidation using a digital computer-based breath-by-breath exercise analysis system during aerobic exercise. Serum 17beta-estradiol concentration was not significantly different between the men and women subjects at baseline (P > .05). Serum free fatty acid concentration tended to be higher in the men than in the women (P = .07) during the exercise, but the respiratory exchange ratio during exercise was lower in women than in men (P < .05). Fat oxidation adjusted for fat-free mass was higher (P < .05) in women than in men. These results suggest that fat utilization was higher during aerobic exercise in postmenopausal obese women than in obese men and did not depend on resting serum 17beta-estradiol concentration.
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Affiliation(s)
- Shigeharu Numao
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Saitama 359-1192, Japan.
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Mittendorfer B, Klein S. Physiological factors that regulate the use of endogenous fat and carbohydrate fuels during endurance exercise. Nutr Res Rev 2009; 16:97-108. [DOI: 10.1079/nrr200357] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
CONTEXT An upper body/visceral fat distribution in obesity is closely linked with metabolic complications, whereas increased lower body fat is independently predictive of reduced cardiovascular risk. EVIDENCE ACQUISITION The measured functions of different fat depots with regards to fatty acid storage and release in health and obesity were reviewed. The adverse effects of experimentally increasing free fatty acid (FFA) concentrations on liver, muscle, pancreatic beta-cell, and endothelial function were noted. EVIDENCE SYNTHESIS The most dramatic abnormality in FFA metabolism is failure to suppress FFA concentrations/adipose tissue lipolysis normally in response to postprandial hyperinsulinemia. Upper body sc fat delivers the majority of FFA to the systemic circulation under postabsorptive and postprandial conditions. In upper body obesity, portal FFA concentrations resulting from both systemic and visceral adipose tissue lipolysis may be significantly greater than arterial FFA concentrations, exposing the liver to even greater amounts of FFA. Visceral fat also releases sufficient IL-6 to increase portal vein IL-6 concentrations, which can affect hepatic metabolism as well. CONCLUSIONS Lower body, upper body sc, and visceral fat depots have unique characteristics with regards to fatty acid metabolism. Selective dysregulation of these depots probably plays an important role with the metabolic complications of obesity.
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Affiliation(s)
- Michael D Jensen
- Endocrine Research Unit, Mayo Clinic, Rochester, Minnesota 55905, USA.
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Lazzer S, Molin M, Stramare D, Facchini S, Francescato MP. Effects of an eight-month weight-control program on body composition and lipid oxidation rate during exercise in obese children. J Endocrinol Invest 2008; 31:509-14. [PMID: 18591882 DOI: 10.1007/bf03346399] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To investigate the effects of an 8-month multidisciplinary weight-control program, including 2 h/week of moderate physical activity, nutritional education lessons and psychological follow-up, on body composition and lipid oxidation rate during exercise in obese children. DESIGN Nineteen (7 boys and 12 girls) obese children, aged 8-12 yr [mean body mass index (BMI) z-score: 2.3 and fat mass: 35.8%] participated in this study. Before and at the end of the weight-control period body composition was assessed by bioelectrical impedance, lipid oxidation rate by indirect calorimetry during a graded exercise test, and time devoted to various activities and energy intake in free-living conditions by questionnaire. RESULTS All children completed the study, at the end of which BMI decreased significantly by mean 0.6+/-0.5 and 0.5+/-0.8 kg/m2, in boys and girls, respectively (p<0.05), and fat mass (FM) decreased by 1.7+/-2.8 and 1.4+/-1.3 kg in boys and girls, respectively (p<0.05). In addition, lipid oxidation rate during exercise increased significantly throughout the graded exercise test up to 21% at maximal lipid oxidation rate which happened at 48+/-5% of maximal oxygen uptake (VO2max), corresponding to 64+/-5% of maximal heart rate. Time spent at sedentary and very light physical activities decreased (p<0.001) to the benefit of recreational activities at home. CONCLUSIONS Multidisciplinary weight-control program, with moderate-intensity physical activities, induced decreases in FM without decreases in free FM, increases in VO2max, lipid oxidation rate during exercise, and time devoted to recreational activities in free-living conditions.
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Affiliation(s)
- S Lazzer
- Department of Biomedical Sciences and Technologies, University of Udine, 33100 Udine, Italy.
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Jocken JWE, Blaak EE, van der Kallen CJH, van Baak MA, Saris WHM. Blunted beta-adrenoceptor-mediated fat oxidation in overweight subjects: a role for the hormone-sensitive lipase gene. Metabolism 2008; 57:326-32. [PMID: 18249203 DOI: 10.1016/j.metabol.2007.10.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2006] [Accepted: 10/15/2007] [Indexed: 10/22/2022]
Abstract
Obesity is associated with blunted beta-adrenoceptor-mediated lipolysis and fat oxidation, which persist after weight reduction. We investigated whether dinucleotide (CA)(n) repeat polymorphisms in intron 6 (i6) or 7 (i7) and a C-60G promoter substitution of the hormone-sensitive lipase (HSL) gene are associated with a blunted in vivo beta-adrenoceptor-mediated increase in circulating fatty acids and glycerol (estimation of lipolytic response) and fat oxidation in overweight-obese subjects. A total of 103 overweight (25 kg/m(2) < or = body mass index < 30 kg/m(2)) and obese (body mass index > or =30 kg/m(2)) subjects (62 men, 41 women) were included. Energy expenditure, respiratory quotient (RQ), and circulating fatty acid and glycerol were determined after stepwise infusion of increasing doses of the nonselective beta-agonist isoprenaline. The i6, i7 (CA)(n) repeat polymorphisms were determined by size-resolved capillary electrophoresis; and a C-60G promoter substitution was determined by restriction enzyme digestion assay. Female noncarriers of allele 184 i7 (n = 18) and female carriers of allele 240 i6 (n = 12) showed an overall reduced fat oxidation (as indicated by changes in RQ) after beta-adrenoceptor-mediated stimulation, explaining, respectively, 6.9% and 20.8% of the variance in RQ. These effects were not seen in male subjects. In conclusion, our results suggest that variation in i7 and i6 of the HSL gene might be associated with a physiological effect on in vivo beta-adrenoceptor-mediated fat oxidation, at least in overweight-obese female subjects.
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Affiliation(s)
- Johan W E Jocken
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands.
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Numao S, Hayashi Y, Katayama Y, Matsuo T, Tomita T, Ohkawara K, Nakata Y, Okura T, Tanaka K. Plasma fat concentration increases in visceral fat obese men during high-intensity endurance exercise. Obes Res Clin Pract 2007; 1:223-90. [DOI: 10.1016/j.orcp.2007.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Revised: 09/06/2007] [Accepted: 10/10/2007] [Indexed: 11/30/2022]
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Abstract
The syndrome of adult GH deficiency and the effects of GH replacement therapy provide a useful model with which to study the effects of the GH/IGF-I axis on exercise physiology. Measures of exercise performance including maximal oxygen uptake and ventilatory threshold are impaired in adult GH deficiency and improved by GH replacement, probably through some combination of increased oxygen delivery to exercising muscle, increased fatty acid availability with glycogen sparing, increased muscle strength, improved body composition, and improved thermoregulation. In normal subjects, in addition to the long-term effects of GH/IGF-I status, there is evidence that the acute GH response to exercise is important in regulating substrate metabolism after exercise. Administration of supraphysiological doses of GH to athletes increases fatty acid availability and reduces oxidative protein loss, particularly during exercise, and increases lean body mass. Despite a lack of evidence that these metabolic effects translate to improved performance, GH abuse by athletes is widespread. Tests to detect GH abuse have been developed based on measurement in serum of 1) indirect markers of GH action, and 2) the relative proportions of the two major naturally occurring isoforms (20 and 22kDa) of GH. There is evidence that exercise performance and strength are improved by administration of GH and testosterone in combination to elderly subjects. The potential benefits of GH in these situations must be weighed against potential adverse effects.
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Affiliation(s)
- James Gibney
- Department of Endocrinology and Diabetes, Adelaide and Mental Hospital, Tallaght, Dublin 24, Ireland
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Braun B, Sharoff C, Chipkin SR, Beaudoin F. Substrate oxidation during exercise: type 2 diabetes is associated with a decrease in lipid oxidation and an earlier shift towards carbohydrate utilization. J Appl Physiol (1985) 2007; 97:991-7. [PMID: 15133003 DOI: 10.1152/japplphysiol.00231.2004] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVES Exercise is a recommended treatment for type 2 diabetes but the actual pattern of metabolic adaptation to exercise in this disease is poorly known and not taken in account in the protocols used. Metabolic defects involved in the pathways of substrate oxidation were described in type 2 diabetes. We hypothesized that type 2 diabetes, regardless of age, gender, training status and weight, could influence by its own the balance of substrates at exercise. METHODS 30 sedentary type 2 diabetic subjects and 38 sedentary matched control subjects were recruited. We used exercise calorimetry to determine lipid and carbohydrate oxidation rates. We calculated two parameters quantifying the balance of substrates induced by increasing exercise intensity: the maximal lipid oxidation point (PLipoxMax) and the Crossover point (COP), intensity from which the part of carbohydrate utilization providing energy becomes predominant on lipid oxidation. RESULTS Lipid oxidation was lower in the diabetic group, independent of exercise intensity. PLipoxMax and COP were lower in the diabetic group [PLipoxMax=25.3+/-1.4% vs. 36.6+/-1.7% %Wmax (P<0.0001)] - COP =24.2+/-2.2% vs. 38.8+/-1.9% %Wmax (P<0.0001). CONCLUSIONS Type 2 diabetes is associated with a decrease in lipid oxidation at exercise and a shift towards a predominance of carbohydrate oxidation for exercise intensities lower than in control subjects. Taking into account these alterations could provide a basis for personalizing training intensity.
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Affiliation(s)
- Barry Braun
- Department of Exercise Science, University of Massachusetts, Amherst 01003, USA.
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Jocken JWE, Blaak EE, Schiffelers S, Arner P, van Baak MA, Saris WHM. Association of a beta-2 adrenoceptor (ADRB2) gene variant with a blunted in vivo lipolysis and fat oxidation. Int J Obes (Lond) 2006; 31:813-9. [PMID: 17130852 DOI: 10.1038/sj.ijo.0803499] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND AND AIMS Obesity is associated with a blunted beta-adrenoceptor-mediated lipolysis and fat oxidation. We investigated whether polymorphisms in codon 16, 27 and 164 of the beta (2)-adrenoceptor gene (ADRB2) and exon 10 of the G protein beta (3)-subunit gene (GNB3) are associated with alterations in in vivo lipolysis and fat oxidation. DESIGN AND METHODS Sixty-five male and 43 female overweight and obese subjects (body mass index (BMI) range: 26.1-48.4 kg/m(2)) were included. Energy expenditure (EE), respiratory quotient (RQ), circulating free fatty acid (FFA) and glycerol levels were determined after stepwise infusion of increasing doses of the non-selective beta-agonist isoprenaline (ISO). RESULTS In women, the Arg16 allele of the ADRB2 gene was associated with a blunted increase in circulating FFA, glycerol and a decreased fat oxidation during ISO stimulation. In men, the Arg16 allele was significantly associated with a blunted increase in FFA but not in glycerol or fat oxidation. CONCLUSION These results suggest that genetic variation in the ADRB2 gene is associated with disturbances in in vivo beta-adrenoceptor-mediated lipolysis and fat oxidation during beta-adrenergic stimulation in overweight and obese subjects; these effects are influenced by gene-gender interactions.
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Affiliation(s)
- J W E Jocken
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands.
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37
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Numao S, Hayashi Y, Katayama Y, Matsuo T, Tomita T, Ohkawara K, Nakata Y, Tanaka K. Effects of obesity phenotype on fat metabolism in obese men during endurance exercise. Int J Obes (Lond) 2006; 30:1189-96. [PMID: 16520811 DOI: 10.1038/sj.ijo.0803282] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The effects of obesity phenotype on fat metabolism during endurance exercise are unclear. This study aimed to investigate in obese men whether body fat distribution would influence plasma fat availability and oxidation during endurance exercise. DESIGN Fourteen sedentary men (body mass index (BMI) > 25 kg/m2) were divided into two groups by visceral fat (VF) area: VF obese (VF-Ob) (n = 7, age; 52.0 +/- 2.5 (s.e.) years) and abdominal subcutaneous fat obese (SF-Ob) (n = 7, age; 57.3 +/- 2.8 (s.e.) years). All participants performed stationary cycling exercise for 60 min at 50% of peak oxygen uptake. MEASUREMENTS Blood and respiratory gas samples were taken for analysis of hormone, metabolite and substrate oxidation in each participant at rest and during exercise. RESULTS There is a significant group x time interaction in the plasma concentration of free fatty acid (FFA) (P < 0.05) and glycerol (P < 0.05) during the exercise bout. In addition, total plasma concentration of FFA (area under the curve) was 59.2% higher in VF-Ob compared with SF-Ob men during endurance exercise (1.99 +/- 0.24 and 1.25 +/- 0.13 mEq/l/min, respectively; P < 0.05). Total plasma concentration of glycerol (area under the curve) was 102.3% higher in VF-Ob than SF-Ob men during the exercise (69.6 +/- 12.5 and 34.4 +/- 5.1 mg/dl/min, respectively; P < 0.05). However, fat oxidation was not different throughout the exercise between VF-Ob and SF-Ob men (176.5 +/- 25.7 and 183.0 +/- 12.8 kcal/60 min, respectively). CONCLUSION During moderate endurance exercise, plasma fat availability may be higher in men with VF obesity compared to men with SF obesity. However, total fat oxidation is similar between obesity phenotype.
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Affiliation(s)
- S Numao
- Graduate school of Comprehensive Human Science, University of Tsukuba, Ibaraki, Japan
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38
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Healy ML, Gibney J, Pentecost C, Croos P, Russell-Jones DL, Sönksen PH, Umpleby AM. Effects of high-dose growth hormone on glucose and glycerol metabolism at rest and during exercise in endurance-trained athletes. J Clin Endocrinol Metab 2006; 91:320-7. [PMID: 16263834 DOI: 10.1210/jc.2005-0916] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Recombinant human-GH (r-hGH), in supraphysiological doses, is self-administered by athletes in the belief that it is performance enhancing. OBJECTIVE The objective of this study was to determine whether r-hGH alters whole-body glucose and glycerol metabolism in endurance-trained athletes at rest and during and after exercise. DESIGN This was a 4-wk double-blind placebo-controlled trial. SETTING This study was conducted at St. Thomas Hospital (London, UK). PARTICIPANTS Twelve endurance-trained male athletes were recruited and randomized to r-hGH (0.2 U/kg.d) (n = 6) or identical placebo (n = 6) for 4 wk. One (placebo group) withdrew after randomization. INTERVENTION Intervention was conducted by randomization to r-hGH (0.2 U/kg x d) or identical placebo for 4 wk. MAIN OUTCOME MEASURES Whole-body rates of appearance (Ra) of glucose and glycerol (an index of lipolysis) and rate of disappearance of glucose were measured using infusions of d-[6-6-2H2]glucose and 2H5-glycerol. RESULTS Plasma levels of glycerol and free fatty acids and glycerol Ra at rest and during and after exercise increased during r-hGH treatment (P < 0.05 vs. placebo). Glucose Ra and glucose rate of disappearance were greater after exercise during r-hGH treatment (P < 0.05 vs. placebo). Resting energy expenditure and fat oxidation were greater under resting conditions during r-hGH treatment (P < 0.05 vs. placebo). CONCLUSIONS r-hGH in endurance-trained athletes increased lipolysis and fatty acid availability at rest and during and after exercise. r-hGH increased glucose production and uptake rates after exercise. The relevance of these effects for athletic performance is not known.
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Affiliation(s)
- M L Healy
- Department of Diabetes and Endocrinology, Guy's, King's and St. Thomas' School of Medicine, St. Thomas Hospital, London SE1 7EH, United Kingdom
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Bennard P, Imbeault P, Doucet E. Maximizing acute fat utilization: effects of exercise, food, and individual characteristics. ACTA ACUST UNITED AC 2005; 30:475-99. [PMID: 16258184 DOI: 10.1139/h05-134] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In discussion of the physiological mechanisms that regulate fat metabolism, and with consideration of the metabolic stimuli that modulate substrate metabolism, the issue of how an acute state of negative lipid balance can be maximized is addressed. The regulation of lipolysis by catecholamines and insulin is reviewed, and the mechanisms of fatty acid mobilization and uptake by muscle are also briefly discussed. The implications of substrate availability and the hormonal response during physiological states such as fasting, exercise, and after food intake are also addressed, with particular regard to the influences on fatty acid mobilization and/or oxidation from eliciting these stimuli conjointly. Finally, a brief discussion is given of both the nature of exercise and the exercising individual, and how these factors influence fat metabolism during exercise. It is also a primary thrust of this paper to underline gaps in the existing literature with regard to exercise timing concerning food ingestion for maximizing acute lipid utilization.
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Affiliation(s)
- Patrick Bennard
- School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
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40
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Abstract
This review gives a broad description of some of the changes in adipose tissue seen in obesity. There are multiple changes in adipose tissue in obesity: histological, neural and vascular, relating to lipid and carbo-hydrate metabolism and to adipose tissue's endocrine functions. Some may originate from a simple physical expansion of cell size and number. It is unclear which are the most important either in terms of intermediary metabolism or of contributing to the co-morbidities of obesity. Important questions for the future include the reversibility of obesity-related changes and indeed whether the changes differ between depots and species. Recent studies examining physiological regulation within adipose tissue demonstrate it to be relatively unresponsive to changes in everyday life.
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Affiliation(s)
- S W Coppack
- Barts and The London, Queen Mary's School of Medicine and Dentistry, Queen Mary, University of London, London E1 2AT, UK.
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41
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Stich V, Berlan M. Physiological regulation of NEFA availability: lipolysis pathway. Proc Nutr Soc 2005; 63:369-74. [PMID: 15294057 DOI: 10.1079/pns2004350] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Plasma NEFA are an important energy substrate and, furthermore, play a key role in the induction of insulin resistance in the body. The availability of NEFA is determined predominantly by their mobilization from adipose tissue triacylglycerol stores by the process of lipolysis. Adipose tissue lipolysis in man is regulated by a number of hormonal and paracrine and/or autocrine signals. The main hormonal signals may be represented by catecholamines, insulin, growth hormone, natriuretic peptides and some adipocytokines. The absolute levels and relative importance and contribution of these signals vary in different physiological situations, with diet and physical exercise being the main physiological variables that affect the hormonal signalling. Thus, modulations in hormonal signals induce an increase in NEFA mobilization in the post-absorptive state and during an acute bout of exercise, and suppress NEFA mobilization in the postprandial state. In addition, hormonal regulation is modified by long-term interventions in energy balance, such as dietary restriction and/or physical training, and is disturbed in some pathological states, such as obesity or diabetes. The question that remains is whether disturbances in lipolysis regulation in obese and diabetic subjects may be 'corrected' by the long-term interventions in diet and physical activity.
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Affiliation(s)
- V Stich
- Franco-Czech Laboratory for Clinical Research of Obesity, Third Faculty of Medicine, Charles University, Prague, Czech Republic.
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42
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Mittendorfer B, Fields DA, Klein S. Excess body fat in men decreases plasma fatty acid availability and oxidation during endurance exercise. Am J Physiol Endocrinol Metab 2004; 286:E354-62. [PMID: 14625204 DOI: 10.1152/ajpendo.00301.2003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The effect of relative body fat mass on exercise-induced stimulation of lipolysis and fatty acid oxidation was evaluated in 15 untrained men (5 lean, 5 overweight, and 5 obese with body mass indexes of 21 +/- 1, 27 +/- 1, and 34 +/- 1 kg/m2, respectively, and %body fat ranging from 12 to 32%). Palmitate and glycerol kinetics and substrate oxidation were assessed during 90 min of cycling at 50% peak aerobic capacity (VO2 peak) by use of stable isotope-labeled tracer infusion and indirect calorimetry. An inverse relationship was found between %body fat and exercise-induced increase in glycerol appearance rate relative to fat mass (r2 = 0.74; P < 0.01). The increase in total fatty acid uptake during exercise [(micromol/kg fat-free mass) x 90 min] was approximately 50% smaller in obese (181 +/- 70; P < 0.05) and approximately 35% smaller in overweight (230 +/- 71; P < 0.05) than in lean (354 +/- 34) men. The percentage of total fatty acid oxidation derived from systemic plasma fatty acids decreased with increasing body fat, from 49 +/- 3% in lean to 39 +/- 4% in obese men (P < 0.05); conversely, the percentage of nonsystemic fatty acids, presumably derived from intramuscular and possibly plasma triglycerides, increased with increasing body fat (P < 0.05). We conclude that the lipolytic response to exercise decreases with increasing adiposity. The blunted increase in lipolytic rate in overweight and obese men compared with lean men limits the availability of plasma fatty acids as a fuel during exercise. However, the rate of total fat oxidation was similar in all groups because of a compensatory increase in the oxidation of nonsystemic fatty acids.
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Affiliation(s)
- Bettina Mittendorfer
- Center for Human Nutrition and Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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43
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Abstract
By far the largest energy reserve in the human body is adipose tissue triglycerides, and these reserves are an important source of fuel during prolonged endurance exercise. To use this rich source of potential energy during exercise, adipose tissue triglycerides must first be hydrolyzed and the resultant fatty acids delivered to the working muscles. The aims of this review are to describe how exercise alters lipid mobilization from adipose tissue, to identify alternative sources of lipids and to discuss some of the key factors regulating fatty acid mobilization, uptake and oxidation during exercise. The impact of understanding factors involved in the coordinated regulation of lipid mobilization and oxidation during exercise goes far beyond its relevance for endurance exercise performance. A better understanding of the regulation of these processes will facilitate the development of more effective treatment modalities for obesity-related metabolic disorders.
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Affiliation(s)
- Jeffrey F Horowitz
- Division of Kinesiology, The University of Michigan, Ann Arbor, MI 48109-2214, USA.
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44
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Nielsen S, Guo Z, Albu JB, Klein S, O'Brien PC, Jensen MD. Energy expenditure, sex, and endogenous fuel availability in humans. J Clin Invest 2003; 111:981-8. [PMID: 12671047 PMCID: PMC152581 DOI: 10.1172/jci16253] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Adipose tissue lipolysis supplies circulating FFAs, which largely meet lipid fuel needs; however, excess FFAs, can contribute to the adverse health consequences of obesity. Because "normal" FFA release has not been well defined, average (mean of 4 days) basal FFA release and its potential regulation factors were measured in 50 lean and obese adults (25 women). Resting energy expenditure (REE), but not body composition, predicted most of the interindividual variation in FFA release. There was a significant, positive linear relationship between palmitate release and REE; however, women released approximately 40% more FFA than men relative to REE. Neither plasma palmitate concentrations nor respiratory quotient by indirect calorimetry differed between men and women. Glucose release rates were not different in men and women whether related to REE or fat free mass. These findings indicate that nonoxidative FFA clearance is greater in women than in men. This could be an advantage at times of increased fuel needs. We conclude that "normal" adipose tissue lipolysis is different in men and women and that the fuel export role of adipose tissue in obesity will need to be reassessed.
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Affiliation(s)
- Søren Nielsen
- Endocrine Research Unit, Mayo Clinic & Foundation, Rochester, Minnesota 55905, USA
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45
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Abstract
Regular physical exercise is of the utmost importance in the treatment of obesity because exercise is one of the factors determining long-term weight maintenance in weight reduction programmes and because exercise has been associated with a reduced risk for developing type 2 diabetes mellitus and cardiovascular disease. Obesity is associated with an impaired utilization of fat as a fuel during post-absorptive conditions, during beta-adrenergic stimulation and possibly during exercise, although the latter data are controversial. One of the underlying mechanisms for the positive effect of exercise training in obesity may be related to its effects on fat utilization because exercise training has been shown to increase basal fat oxidation and exercise fat oxidation in lean volunteers. Data on the effect of aerobic exercise training on exercise fat oxidation are controversial, whereas the available data indicate that exercise training may not be able to increase resting fat oxidation or 24-hour fat oxidation in obese subjects. Because disturbed muscle fat oxidation may be a primary event in the aetiology of obesity it is of the utmost importance to obtain more information on how and whether exercise training may be able to compensate for these impairments.
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Affiliation(s)
- Ellen E Blaak
- Department of Human Biology, Nutrition Research Centre, Maastricht University, The Netherlands
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46
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Rizza RA, Jensen MD, Nair KS. Type I Diabetes Mellitus (Insulin‐Dependent Diabetes Mellitus). Compr Physiol 2001. [DOI: 10.1002/cphy.cp070236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Abstract
Regulation of lipid mobilization and oxidation during exercise in obesity. Exerc. Sport Sci. Rev. Vol. 29, No. 1, pp 42-46, 2001. Obesity is associated with metabolic disorders that may be related to alterations in lipid mobilization and oxidation. Although exercise is essential for successful weight management, the regulation of fatty acid metabolism during exercise in obesity is unclear. This review discusses factors that regulate fat metabolism during exercise and the effects of endurance training on these responses.
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Affiliation(s)
- J F Horowitz
- Division of Kinesiology, University of Michigan, Ann Arbor, Michigan, USA.
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48
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van Aggel-Leijssen DP, Saris WH, Wagenmakers AJ, Hul GB, van Baak MA. The effect of low-intensity exercise training on fat metabolism of obese women. OBESITY RESEARCH 2001; 9:86-96. [PMID: 11316351 DOI: 10.1038/oby.2001.11] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Previous studies have shown that fat metabolism is different in upper body (UB) and lower body (LB) obese women. The present study investigated whether the effect of low-intensity exercise training on fat metabolism is different in UB and LB obese premenopausal women. RESEARCH METHODS AND PROCEDURES Twenty-one healthy, premenopausal women with either LB obesity (waist-to-hip ratio of < or =0.79; n = 8) or UB obesity (waist-to-hip ratio of > or =0.85; n = 13) participated in the present study. The UB obese women were matched and randomly divided in an exercise training group (UB) and a nonexercising control group (UB-C). Subjects in the UB and LB groups participated in a low-intensity exercise training program (40% VO2max) three times per week for 12 weeks. Before and after the intervention, measurements of fat metabolism at rest and during exercise, body composition, and maximal aerobic capacity were performed. RESULTS Exercise training did not change the respiratory exchange ratio at rest in the UB and LB groups. During exercise, relative fat oxidation increased in the UB group by 19% (p < 0.05), whereas no change in the LB and UB-C groups was found. Plasma free fatty acid oxidation did not change by exercise training, and nonplasma fatty acid oxidation tended to increase in the UB group compared with the UB-C group (p = 0.08). DISCUSSION Low-intensity exercise training increased the contribution of fat oxidation to total energy expenditure during exercise but not at rest in UB obese women. Exercise training had no significant effect on fat metabolism in the LB obese women.
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Affiliation(s)
- D P van Aggel-Leijssen
- Nutrition, Toxicology and Environmental Research Institute, Department of Human Biology, Maastricht University, The Netherlands.
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49
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Horowitz JF, Klein S. Oxidation of nonplasma fatty acids during exercise is increased in women with abdominal obesity. J Appl Physiol (1985) 2000; 89:2276-82. [PMID: 11090579 DOI: 10.1152/jappl.2000.89.6.2276] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We evaluated plasma fatty acid availability and plasma and whole body fatty acid oxidation during exercise in five lean and five abdominally obese women (body mass index = 21 +/- 1 vs. 38 +/- 1 kg/m(2)), who were matched on aerobic fitness, to test the hypothesis that obesity alters the relative contribution of plasma and nonplasma fatty acids to total energy production during exercise. Subjects exercised on a recumbent cycle ergometer for 90 min at 54% of their peak oxygen consumption. Stable isotope tracer methods ([(13)C]palmitate) were used to measure fatty acid rate of appearance in plasma and the rate of plasma fatty acid oxidation, and indirect calorimetry was used to measure whole body substrate oxidation. During exercise, palmitate rate of appearance increased progressively and was similar in obese and lean groups between 60 and 90 min of exercise [3.9 +/- 0.4 vs. 4.0 +/- 0.3 micromol. kg fat free mass (FFM)(-1). min(-1)]. The rate of plasma fatty acid oxidation was also similar in obese and lean subjects (12.8 +/- 1.7 vs. 14.5 +/- 1.8 micromol. kg FFM(-1). min(-1); P = not significant). However, whole body fatty acid oxidation during exercise was 25% greater in obese than in lean subjects (21.9 +/- 1.2 vs. 17.5 +/- 1.6 micromol. kg FFM(-1). min(-1); P < 0.05). These results demonstrate that, although plasma fatty acid availability and oxidation are similar during exercise in lean and obese women, women with abdominal obesity use more fat as a fuel by oxidizing more nonplasma fatty acids.
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Affiliation(s)
- J F Horowitz
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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50
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Abstract
Endogenous triacylglycerols represent an important source of fuel for endurance exercise. Triacylglycerol oxidation increases progressively during exercise; the specific rate is determined by energy requirements of working muscles, fatty acid delivery to muscle mitochondria, and the oxidation of other substrates. The catecholamine response to exercise increases lipolysis of adipose tissue triacylglycerols and, presumably, intramuscular triacylglycerols. In addition, increases in adipose tissue and muscle blood flow decrease fatty acid reesterification and facilitate the delivery of released fatty acids to skeletal muscle. Alterations in fatty acid mobilization and the relative use of adipose and intramuscular triacylglycerols during exercise depend, in large part, on degree of fitness and exercise intensity. Compared with untrained persons exercising at the same absolute intensity, persons who have undergone endurance training have greater fat oxidation during exercise without increased lipolysis. Available evidence suggests that the training-induced increase in fat oxidation is due primarily to increased oxidation of non-plasma-derived fatty acids, perhaps from intramuscular triacylglycerol stores. Fat oxidation is lower in high-intensity exercise than in moderate-intensity exercise, in part because of decreased fatty acid delivery to exercising muscles. Parenteral lipid supplementation during high-intensity exercise increases fat oxidation, but the effect of ingesting long-chain or medium-chain triacylglycerols on substrate metabolism during exercise is less clear. This review discusses the relation between fatty acid mobilization and oxidation during exercise and the effect of endurance training, exercise intensity, and lipid supplementation on these responses.
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Affiliation(s)
- J F Horowitz
- Department of Internal Medicine, Washington University School of Medicine, St Louis, MO 63110-1093, USA
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