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Impact of a weight loss and fitness intervention on exercise-associated plasma oxylipin patterns in obese, insulin-resistant, sedentary women.
Grapov, D, Fiehn, O, Campbell, C, Chandler, CJ, Burnett, DJ, Souza, EC, Casazza, GA, Keim, NL, Hunter, GR, Fernandez, JR, et al
Physiological reports. 2020;(17):e14547
Abstract
Very little is known about how metabolic health status, insulin resistance or metabolic challenges modulate the endocannabinoid (eCB) or polyunsaturated fatty acid (PUFA)-derived oxylipin (OxL) lipid classes. To address these questions, plasma eCB and OxL concentrations were determined at rest, 10 and 20 min during an acute exercise bout (30 min total, ~45% of preintervention V̇O2peak , ~63 W), and following 20 min recovery in overnight-fasted sedentary, obese, insulin-resistant women under controlled diet conditions. We hypothesized that increased fitness and insulin sensitivity following a ~14-week training and weight loss intervention would lead to significant changes in lipid signatures using an identical acute exercise protocol to preintervention. In the first 10 min of exercise, concentrations of a suite of OxL diols and hydroxyeicosatetraenoic acid (HETE) metabolites dropped significantly. There was no increase in 12,13-DiHOME, previously reported to increase with exercise and proposed to activate muscle fatty acid uptake and tissue metabolism. Following weight loss intervention, exercise-associated reductions were more pronounced for several linoleate and alpha-linolenate metabolites including DiHOMEs, DiHODEs, KODEs, and EpODEs, and fasting concentrations of 9,10-DiHODE, 12,13-DiHODE, and 9,10-DiHOME were reduced. These findings suggest that improved metabolic health modifies soluble epoxide hydrolase, cytochrome P450 epoxygenase (CYP), and lipoxygenase (LOX) systems. Acute exercise led to reductions for most eCB metabolites, with no evidence for concentration increases even at recovery. It is proposed that during submaximal aerobic exercise, nonoxidative fates of long-chain saturated, monounsaturated, and PUFAs are attenuated in tissues that are important contributors to the blood OxL and eCB pools.
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Metabolic adaptation is an illusion, only present when participants are in negative energy balance.
Martins, C, Roekenes, J, Salamati, S, Gower, BA, Hunter, GR
The American journal of clinical nutrition. 2020;(5):1212-1218
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BACKGROUND The existence of metabolic adaptation, following weight loss, remains a controversial issue. To our knowledge, no study has evaluated the role of energy balance (EB) in modulating metabolic adaptation. OBJECTIVES The aim of this study was to determine if metabolic adaptation, at the level of resting metabolic rate (RMR), is modulated by participants' EB status. A secondary aim was to investigate if metabolic adaptation was associated with weight regain. METHODS Seventy-one individuals with obesity (BMI: 34.6 ± 3.4 kg/m2; age: 45.4 ± 8.2 y; 33 men) enrolled in a 1000-kcal/d diet for 8 wk, followed by 4 wk of weight stabilization and a 9-mo weight loss maintenance program. Body weight/composition and RMR were measured at baseline, week 9 (W9), week 13 (W13), and 1 y (1Y). Metabolic adaptation was defined as a significantly different (lower or higher) measured compared with predicted RMR. RESULTS Participants lost on average 14 kg by W9, followed by weight stabilization at W13, and regained 29% of their initial weight loss at 1Y. Metabolic adaptation was found at W9 (-92 ± 110 kcal/d, P < 0.001) and W13 (-38 ± 124 kcal/d, P = 0.011) but was not correlated with weight regain. A significant reduction in metabolic adaptation was seen between W9 and W13 (-53 ± 101 kcal/d, P < 0.001). In a subset of participants who gained weight between W9 and W13 (n = 33), no metabolic adaptation was seen at W13 (-26.8 ± 121.5 kcal/d, P = 0.214). In a subset of participants with data at all time points (n = 45), metabolic adaptation was present at W9 and W13 (-107 ± 102 kcal/d, P < 0.001 and -49 ± 128 kcal/d, P = 0.013) but not at 1Y (-7 ± 129, P = 0.701). CONCLUSION After weight loss, metabolic adaptation at the level of RMR is dependent on the EB status of the participants, being reduced to half after a period of weight stabilization. Moreover, metabolic adaptation does not predict weight regain at 1Y follow-up. These trials were registered at clinicaltrials.gov as NCT02944253 and NCT03287726.
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Exercise training and/or diet on reduction of intra-abdominal adipose tissue and risk factors for cardiovascular disease.
Borges, JH, Carter, SJ, Bryan, DR, Hunter, GR
European journal of clinical nutrition. 2019;(7):1063-1068
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BACKGROUND/OBJECTIVES To test the effects of weight loss with and without exercise training (aerobic or resistance) on intra-abdominal adipose tissue (IAAT) and risk factors for cardiovascular disease (CVD). Additionally, CVD risk factors was evaluated before and after weight loss using previously established IAAT cut-points. SUBJECTS/METHODS One hundred twenty-two overweight premenopausal women were randomly assigned to one of three groups: (1) diet only (Diet); (2) diet and aerobic training (Diet + AT); or (3) diet and resistance training (Diet + RT); until a BMI of < 25 kg/m2 was reached. Computerized tomography was used to measure IAAT and blood lipids were measured by assay. Evaluations were made before and after weight loss. RESULTS Though no group-by-time effects were found after weight loss, we observed significant time effects for: IAAT (-38.0%, P < 0.001), total cholesterol (TC) (-2.2%, P = 0.008), low-density lipoprotein cholesterol (LDL-C) (-4.8%, P < 0.001), high-density lipoprotein cholesterol (HDL-C) (+20.2%, P < 0.001), triglycerides (-18.7%, P < 0.001), TC/HDL-C (-16.3%, P < 0.001), and LDL-C/HDL-C (-18.0%, P < 0.001). Following weight loss, 40.2% of all participants reduced IAAT to < 40 cm2 (IAAT associated with low CVD risk). Furthermore, only 2.5% of participants had an IAAT > 110 cm2 (IAAT associated with high CVD risk) after weight loss. We also observed that decreases of IAAT were associated with decreased CVD risk factors after weight loss independent of race, changes in %fat mass and changes in maximal oxygen uptake. CONCLUSIONS Caloric restriction leading to significant weight loss with or without exercise training appears to be equally effective for reducing IAAT and CVD risk factors.
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Inverse association between changes in energetic cost of walking and vertical accelerations in non-metastatic breast cancer survivors.
Carter, SJ, Rogers, LQ, Bowles, HR, Norian, LA, Hunter, GR
European journal of applied physiology. 2019;(11-12):2457-2464
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PURPOSE With accelerometry, the utility to detect changes in physical activity are predicated on the assumption that walking energetics and gait mechanics do not change. The present work examined associations between changes (∆) in walking energetics, exercise self-efficacy, and several accelerometer-derived metrics. METHODS Secondary analyses were performed among a sub-sample (n = 29) of breast cancer survivors participating in a larger randomized trial. During 4 min of treadmill walking (0.89 m s-1, 0% grade), indirect calorimetry quantified steady-state energy expenditure (EE), wherein, participants were fitted with a heart rate monitor and hip-worn triaxial accelerometer. Exercise self-efficacy was measured using a 9-item questionnaire, while vector magnitude (VM) and individual planes (e.g., mediolateral, vertical, and anteroposterior) of the movement were extracted for data analyses. Evaluations were made at baseline and after 3 months. RESULTS From baseline to 3 months, the energetic cost of walking (kcals min-1) significantly decreased by an average of - 5.1% (p = 0.001; d = 0.46). Conversely, VM significantly increased (p = 0.007; d = 0.53), exclusively due to greater vertical accelerations (acc) (+ 5.7 ± 7.8 acc; p = 0.001; d = 0.69). Changes in vertical accelerations were inversely and positively associated with ∆walking EE (r = - 0.37; p = 0.047) and ∆exercise self-efficacy (r = 0.39; p = 0.034), respectively. CONCLUSION Hip-worn accelerometers do not appear well-suited to correctly detect changes in ease of walking as evidenced by reduced energetic cost. Further research should determine if a divergence between measured EE and vertical accelerations could contribute to erroneous inferences in free-living physical activity.
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Adaptive thermogenesis and changes in body composition and physical fitness in army cadets.
Borges, JH, Hunter, GR, Silva, AM, Cirolini, VX, Langer, RD, Páscoa, MA, Guerra-Júnior, G, Gonçalves, EM
The Journal of sports medicine and physical fitness. 2019;(1):94-101
Abstract
BACKGROUND To analyze the association between a 34-week military training on body composition, physical fitness and compensatory changes in resting energy expenditure (REE) recognized as adaptive thermogenesis (AT). We also explored if regional body composition changes were related to AT. METHODS Twenty-nine male army cadets, aged 17 to 22 years were tested at baseline (T0) and after 34-weeks military training (T1). Physical training was performed 5 days/week during 90 minutes/day. Measurements included body composition by dual-energy x-ray absorptiometry; physical fitness by 3000-m running, pull-up, 50-m freestyle swimming, push-up and sit-up tests; REE measured by indirect calorimetry (REEm) and predicted from fat-free mass (FFM), fat mass (FM) and ethnicity at T0 (REEp). %AT was calculated using values at T1: 100(REEm/REEp-1); and AT (kcal/day) as %AT/100 multiplied by baseline REEm. RESULTS Physical training was associated with increases of lean soft tissue (LST) (∆1.2±1.3 kg), FM (∆1.4±1.3 kg), FFM (∆1.2±1.3 kg) and physical fitness (P<0.01), but no REE changes (∆59.6±168.9 kcal/day) and AT were observed (P>0.05). Though a large variability was found, AT was partially explained by trunk LST (r2=0.17, P=0.027). Individuals showing a higher AT response demonstrated a higher trunk LST increase (∆0.8±0.7 kg, P<0.05). CONCLUSIONS The military training increased LST, FM, FFM and physical fitness. Though no mean changes in AT occurred, a large individual variability was observed with some participants increasing REE beyond the expected body composition changes, suggesting a spendthrift phenotype. Changes of trunk LST may play an important role in the AT response observed in these individuals.
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Oral Supplementation with Beta-Hydroxy-Beta-Methylbutyrate, Arginine, and Glutamine Improves Lean Body Mass in Healthy Older Adults.
Ellis, AC, Hunter, GR, Goss, AM, Gower, BA
Journal of dietary supplements. 2019;(3):281-293
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Oral intake of beta-hydroxy-beta-methylbutyrate (HMB), arginine, and glutamine may ameliorate muscle loss by stimulating protein synthesis and decreasing protein degradation while simultaneously decreasing inflammation. Previous studies provide evidence for improvement in body composition with dietary supplementation of these ingredients among patients with muscle-wasting diseases. The objectives of this study were to examine the effects of this amino acid mixture on lean body mass, muscle volume, and physical function among healthy older adults. Thirty-one community-dwelling men and women, aged 65-89 years, were randomized to either two oral doses of the amino acid supplement (totaling 3 g HMB, 14 g arginine, 14 g glutamine) or placebo daily for six months. At baseline and month six, lean body mass was measured by air displacement plethysmography, dual-energy X-ray absorptiometry (DXA), and four-compartment model. Muscle volume of quadriceps was quantified by magnetic resonance imaging (MRI), and participants performed a battery of tests to assess physical function. As compared to the placebo group, the treatment group exhibited improvement in a timed stair climb (p =.016) as well as significant increases in lean body mass by all methods of assessment (p <.05). Regional analysis by DXA revealed increased arm lean mass in the supplement group only (p =.035). However, no change was observed in MRI-derived quadriceps volume. Dietary supplementation with HMB, arginine, and glutamine improved total body lean mass among a small sample of healthy older adults. Further research is indicated to elucidate mechanisms of action and to determine whether supplementation may benefit frail elders. Registered under ClinicalTrials.gov identifier no. NCT01057082.
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Dietary Changes Impact the Gut Microbe Composition in Overweight and Obese Men with Prostate Cancer Undergoing Radical Prostatectomy.
Frugé, AD, Ptacek, T, Tsuruta, Y, Morrow, CD, Azrad, M, Desmond, RA, Hunter, GR, Rais-Bahrami, S, Demark-Wahnefried, W
Journal of the Academy of Nutrition and Dietetics. 2018;(4):714-723.e1
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BACKGROUND Diet and obesity influence prostate cancer risk and progression-effects that may be mediated through the gut microbiome. OBJECTIVE Our aim was to explore relationships among diet, gut microbes, and Gleason sum in overweight and obese prostate cancer patients enrolled in a presurgical weight-loss trial. DESIGN Randomized controlled trial (NCT01886677) secondary analysis. PARTICIPANTS/SETTING In 2013-2014, 40 prostate cancer patients in the southeastern United States were randomized and allocated equally to weight-loss and wait-list control arms while they awaited prostatectomy; stool samples were collected on a subset of 22 patients. INTERVENTION Registered dietitian nutritionists and exercise physiologists provided semi-weekly in-person and telephone-based guidance on calorie-restricted diets and exercise to promote an approximate weight loss of 0.91 kg/wk. MAIN OUTCOME MEASURES Baseline and follow-up 24-hour dietary recalls were conducted and analyzed (using the Automated Self-Administered 24-hour dietary recall system; National Cancer Institute, Bethesda, MD) for macronutrients, micronutrients, and food groups. Microbiome analysis targeting the V4 region of the 16S ribosomal RNA gene was performed on fecal samples. Biopsy Gleason sum data were accessed from diagnostic pathology reports. STATISTICAL ANALYSES PERFORMED Associations between dietary factors and operational taxonomic units were determined by β-diversity analysis. Wilcoxon signed rank, and Mann-Whitney U testing assessed within- and between-arm differences. Associations between Gleason sum and operational taxonomic units, and diet and operational taxonomic units, were analyzed using Spearman correlations. RESULTS At baseline, Proteobacteria (median 0.06, interquartile range 0.01 to 0.16) were abundant, with four orders positively associated with Gleason sum. Gleason sum was associated with Clostridium (ρ=.579; P=0.005) and Blautia (ρ=-0.425, P=0.049). Increased red meat consumption from baseline was associated with Prevotella (ρ=-.497; P=0.018) and Blautia (ρ=.422; P=0.039). Men who increased poultry intake had decreased Clostridiales abundance (P=0.009). CONCLUSIONS This hypothesis-generating study provides a starting point for investigating the relationships between the fecal microbiome, diet, and prostate cancer. Adequately powered studies are required to further explore and validate these findings.
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Racial Differences in Relative Skeletal Muscle Mass Loss During Diet-Induced Weight Loss in Women.
Hunter, GR, Bryan, DR, Borges, JH, David Diggs, M, Carter, SJ
Obesity (Silver Spring, Md.). 2018;(8):1255-1260
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OBJECTIVE It is unclear whether there are race-specific differences in the maintenance of skeletal muscle during energy restriction. Changes in relative skeletal muscle index (RSMI; limb lean tissue divided by height squared) were compared following (1) diet alone, (2) diet + aerobic training, or (3) diet + resistance training. METHODS Overweight, sedentary African American (AA; n = 72) and European American (EA; n = 68) women were provided an 800-kcal/d diet to reduce BMI < 25 kg/m2 . Regional fat-free mass was measured with dual-energy x-ray absorptiometry. Steady-state VO2 and heart rate responses during walking were measured. RESULTS AA women had greater RSMI and preserved RSMI during diet alone, while RSMI was significantly reduced among EA women (EA women -3.6% vs. AA women + 1.1%; P < 0.05). Diet + resistance training subjects retained RSMI (EA women + 0.2% vs. AA women + 1.4%; P = 50.05), whereas diet + aerobic training subjects decreased RSMI (EA women -1.4% vs. AA women -1.5%; P < 0.05). Maintenance of RSMI was related to delta walking ease and economy. CONCLUSIONS Compared with AA women, EA women are less muscular and lose more muscle during weight loss without resistance training. During diet-induced weight loss, resistance training preserves skeletal muscle, especially among premenopausal EA women. Maintenance of muscle during weight loss associates with better ease and economy of walking.
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Ease of walking associates with greater free-living physical activity and reduced depressive symptomology in breast cancer survivors: pilot randomized trial.
Carter, SJ, Hunter, GR, Norian, LA, Turan, B, Rogers, LQ
Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer. 2018;(5):1675-1683
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PURPOSE We hypothesized exercise training-induced improvements in ease of walking would associate with favorable changes in objectively measured physical activity (PA) and self-reported depressive symptoms following a PA behavior-change intervention in non-metastatic breast cancer survivors (BCS). METHODS Twenty-seven BCS received random assignment to an intervention (INT) or control group (CON). INT included counseling/group discussions coupled with supervised exercise tapered to unsupervised exercise. PA, depressive symptoms, and ease of walking were evaluated pre-/post-intervention using 10-day accelerometry, HADS depression subscale, and indirect calorimetry during a standardized treadmill test, respectively. PA composite score was calculated by converting weekly minutes of moderate-to-vigorous PA and average steps/day to z-scores then dividing the sum by 2. Cardiac efficiency was determined by dividing steady-state oxygen uptake by heart rate to evaluate the volume of oxygen consumed per heartbeat. RESULTS ANCOVA revealed a significant time by group interaction showing the INT group exhibited greater positive changes in the PA composite compared to the CON (INT, + 0.14 ± 0.66 au vs. CON, - 0.48 ± 0.49 au; p = 0.019; η p2 = 0.21). Changes occurring from baseline to follow-up, among all participants, revealed improved ease of walking (less oxygen uptake) associated with increased PA composite (r = - 0.52; p = 0.010) and lower depressive symptomology (r = 0.50; p = 0.012) adjusted for age, race, and months since cancer diagnosis. Increased cardiac efficiency during the standardized treadmill test also associated with less daily sedentary time (r = - 0.52; p = 0.021). CONCLUSIONS These data support the assertion that reducing the physiological difficulty of walking may contribute to greater engagement in free-living PA, less sedentary time, and decreased psychosocial distress among BCS.
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Inverse relationship between changes of maximal aerobic capacity and changes in walking economy after weight loss.
Borges, JH, Carter, SJ, Singh, H, Hunter, GR
European journal of applied physiology. 2018;(8):1573-1578
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PURPOSE The aims of this study were to: (1) determine the relationships between maximum oxygen uptake ([Formula: see text]O2max) and walking economy during non-graded and graded walking among overweight women and (2) examine potential differences in [Formula: see text]O2max and walking economy before and after weight loss. METHODS One-hundred and twenty-four premenopausal women with a body mass index (BMI) between 27 and 30 kg/m2 were randomly assigned to one of three groups: (a) diet only; (b) diet and aerobic exercise training; and (c) diet and resistance exercise training. All were furnished with standard, very-low calorie diet to reduce BMI to < 25 kg/m2. [Formula: see text]O2max was measured using a modified-Bruce protocol while walking economy (1-net [Formula: see text]O2) was obtained during fixed-speed (4.8 k·h-1), steady-state treadmill walking at 0% grade and 2.5% grade. Assessments were conducted before and after achieving target BMI. RESULTS Prior to weight loss, [Formula: see text]O2max was inversely related (P < 0.05) with non-graded and graded walking economy (r = - 0.28 to - 0.35). Similar results were also observed following weight loss (r = - 0.22 to - 0.28). Additionally, we also detected a significant inverse relationship (P < 0.05) between the changes (∆, after weight loss) in ∆[Formula: see text]O2max, adjusted for fat-free mass, with non-graded and graded ∆walking economy (r = - 0.37 to - 0.41). CONCLUSIONS Our results demonstrate [Formula: see text]O2max and walking economy are inversely related (cross-sectional) before and after weight loss. Importantly though, ∆[Formula: see text]O2max and ∆walking economy were also found to be inversely related, suggesting a strong synchrony between maximal aerobic capacity and metabolic cost of exercise.