Regulation of fat metabolism during resistance exercise in sedentary lean and obese men

Full-body resistance training promotes greater fat mass loss than a split-body routine in well-trained males: A randomized trial

While significant progress has been made in understanding the resistance training (RT) strategy for muscle hypertrophy increase, there remains limited knowledge about its impact on fat mass loss. This study aimed to investigate whether full-body is superior to split-body routine in promoting fat mass loss among well-trained males. Twenty-three participants were randomly assigned to 1 of 2 groups: full-body (n = 11, training muscle groups 5 days per week) and split-body (n = 12, training muscle groups 1 day per week). Both groups performed a weekly set volume-matched condition (75 sets/week, 8-12 repetition maximum at 70%-80 % of 1RM) for 8 weeks, 5 days per week with differences only in the routine. Whole-body and regional fat were assessed using DXA at the beginning and at the end of the study. Full-body RT elicited greater losses compared to split-body in whole-body fat mass (-0.775 ± 1.120 kg vs. +0.317 ± 1.260 kg; p = 0.040), upper-limb fat mass (-0.085 ± 0.118 kg vs. +0.066 ± 0.162 kg; p = 0.019), gynoid fat mass (-0.142 ± 0.230 kg vs. +0.123 ± 0.230 kg; p = 0.012), lower-limb fat mass (-0.197 ± 0.204 kg vs. +0.055 ± 0.328 kg; p = 0.040), and a trend in interaction in android fat mass (-0.116 ± 0.153 kg vs. +0.026 ± 0.174 kg; p = 0.051), with large effects sizes (η2 p ≥ 0.17). This study provides evidence that full-body is more effective in reducing whole-body and regional fat mass compared to split-body routine in well-trained males.

Cold Ambient Temperature Does Not Alter Subcutaneous Abdominal Adipose Tissue Lipolysis and Blood Flow in Endurance-Trained Cyclists

This study sought to investigate the effect of cold ambient temperature on subcutaneous abdominal adipose tissue (SCAAT) lipolysis and blood flow during steady-state endurance exercise in endurance-trained cyclists. Ten males (age: 23 ± 3 years; peak oxygen consumption: 60.60 ± 4.84 ml·kg-1·min-1; body fat: 18.4% ± 3.5%) participated in baseline lactate threshold (LT) and peak oxygen consumption testing, two familiarization trials, and two experimental trials. Experimental trials consisted of cycling in COLD (3 °C; 42% relative humidity) and neutral (NEU; 19 °C; 39% relative humidity) temperatures. Exercise consisted of 25 min cycling at 70% LT and 25 min at 90% LT. In situ SCAAT lipolysis and blood flow were measured via microdialysis. Heart rate, core temperature, carbohydrate and fat oxidation, blood glucose, and blood lactate were also measured. Heart rate, core temperature, oxygen consumption, and blood lactate increased with exercise but were not different between COLD and NEU. SCAAT blood flow did not change from rest to exercise or between COLD and NEU. Interstitial glycerol increased during exercise (p < .001) with no difference between COLD and NEU. Fat oxidation increased (p < .001) at the onset of exercise and remained elevated thereafter with no difference between COLD and NEU. Carbohydrate oxidation increased with increasing exercise intensity and was greater at 70% LT in COLD compared to NEU (p = .030). No differences were observed between conditions for any other variable. Cycling exercise increased SCAAT lipolysis but not blood flow. Ambient temperature did not alter SCAAT metabolism, SCAAT blood flow, or fat oxidation in well-trained cyclists, though cold exposure increased whole-body carbohydrate oxidation at lower exercise intensities.

Effects of resistance training on muscular strength, endurance, body composition and functional performance among sarcopenic patients: a systematic review

Background

Sarcopenia, a gradual loss of muscle mass and strength associated with ageing, contributes to a decline in physical abilities, increase in disability and frailty and loss of functional independence. This functional deterioration which comes with ageing, can be slowed in pace with exercise.

Objective

The objective of the current review was to thoroughly search for literature assessing impact of RT on physical performance, body composition, muscle strength and endurance in sarcopenic elderly patients.

Methods

PubMed, Scopus, Web of Science, and PEDro databases were brought in use for a thorough search for articles published from 2010 to 2023. Two researchers independently retrieved data from studies that complied with the inclusion and exclusion criteria, while they also evaluated quality of the evidence.

Results

In total, 14 studies with 742 patients with mean age of 72.4 ± 9.22 years were included in the analysis for this review. Results indicate, RT improves body composition (p = 0.001), functional performance (p 0.001), postural stability (p = 0.005) and muscle strength (p 0.001) in elderly sarcopenic patients.

Conclusion

A promising intervention for the management of sarcopenia is RT. To yield RT's positive effects, a well-designed prescription is the need of the hour, just like it is with other treatment strategies.

Fish Oil Supplementation with Resistance Exercise Training Enhances Physical Function and Cardiometabolic Health in Postmenopausal Women

Menopause is a condition associated with an increased risk of dysregulation in cardiovascular and metabolic health among older women. While fish oil (FO) has garnered great attention for its health-enhancing properties, its potential for enhancing cardiometabolic health in this demographic remains to be established. The purpose of this study was to determine the clinical efficacy of an 8 wk administration of FO combined with programmed resistance exercise training (RET) on physical function and risk factors associated with cardiometabolic health in healthy older women. Twenty, healthy, older women were randomly assigned to one of the two experimental groups: resistance training with placebo (RET-PL) or RET with fish oil (RET-FO). Physical function, blood pressure (BP), triglyceride (TG), and systemic inflammation and oxidative stress biomarkers were assessed before and after the intervention. Statistical significance was set at p ≤ 0.05. Physical function was greatly enhanced in both RET and RET-FO. Handgrip strength substantially increased only in RET-FO. RET-FO exhibited significant decreases in BP, TG, inflammatory cytokines (TNF-α and IL-6), and oxidative stress (MDA and 8-OHdG) levels, while no detectable changes were found in RET-PL. Our findings indicate that FO administration during 8 wks of RET appears to enhance muscle function and lower risk factors linked to cardiometabolic disorders in postmenopausal women.

Does Obesity Affect Neuromuscular and Cardiovascular Adaptations after a 3-Month Combined Exercise Program in Untrained Premenopausal Middle-Aged Women?

Previous studies indicated different acute adaptations between obese and lean individuals, while there is limited information with conflicting results regarding long-term adaptations. The aim of this study was to compare the efficacy of a 3-month integrated combined training between obese and lean middle-aged untrained premenopausal women. In total, 72 women (36 obese/36 lean) were divided into four groups: (a) obese exercise (OB-EG), (b) obese control (OB-CG), (c) lean exercise (L-EG), and (d) lean control (L-CG). The exercise groups followed a 3-month (3 times/week) integrated combined aerobic and strength training program. Health indices (body composition, body circumferences, blood pressure, respiratory function), functional capacity (flexibility, balance), and physical fitness (strength, aerobic capacity) were measured before and after the 3-month time period. Participants' enjoyment was also assessed following the program. OB-EG and L-EG significantly improved (p < 0.05) similarly across all functional capacity and physical fitness indices (10-76%; depending on the evaluation index), except balance and strength indices of the non-preferred limb where OB-EG showed greater improvement (reducing the existing pre-training strength/balance asymmetries) than L-EG. Furthermore, both obese and lean individuals showed similarly high levels of enjoyment. This program could be effectively used in fitness settings causing similar neuromuscular and cardiovascular adaptations in obese and lean women.

The Regulation of Fat Metabolism During Aerobic Exercise

Since the lipid profile is altered by physical activity, the study of lipid metabolism is a remarkable element in understanding if and how physical activity affects the health of both professional athletes and sedentary subjects. Although not fully defined, it has become clear that resistance exercise uses fat as an energy source. The fatty acid oxidation rate is the result of the following processes: (a) triglycerides lipolysis, most abundant in fat adipocytes and intramuscular triacylglycerol (IMTG) stores, (b) fatty acid transport from blood plasma to muscle sarcoplasm, (c) availability and hydrolysis rate of intramuscular triglycerides, and (d) transport of fatty acids through the mitochondrial membrane. In this review, we report some studies concerning the relationship between exercise and the aforementioned processes also in light of hormonal controls and molecular regulations within fat and skeletal muscle cells.

Effect of Fat Mass Localization on Fat Oxidation During Endurance Exercise in Women

Independent of total body fat mass, predominant upper body fat mass distribution is strongly associated with cardio-metabolic comorbidities. However, the mechanisms underlying fat mass localization are not fully understood. Although a large body of evidence indicates sex-specific fat mass distribution, women are still excluded from many physiological studies and their specific features have been investigated only in few studies. Moreover, endurance exercise is an effective strategy for improving fat oxidation, suggesting that regular endurance exercise could contribute to the management of body composition and metabolic health. However, no firm conclusion has been reached on the effect of fat mass localization on fat oxidation during endurance exercise. By analyzing the available literature, this review wants to determine the effect of fat mass localization on fat oxidation rate during endurance exercise in women, and to identify future research directions to advance our knowledge on this topic. Despite a relatively limited level of evidence, the analyzed studies indicate that fat oxidation during endurance exercise is higher in women with lower upper-to-lower-body fat mass ratio than in women with higher upper-to-lower-body fat mass ratio. Interestingly, obesity may blunt the specific effect of upper and lower body fat mass distribution on fat oxidation observed in women with normal weight during endurance exercise. Studying and understanding the physiological responses of women to exercise are essential to develop appropriate physical activity strategies and ultimately to improve the prevention and treatment of cardio-metabolic diseases.

Substitution of parts of aerobic training by resistance training lowers fasting hyperglycemia in individuals with metabolic syndrome

We sought to determine the effects of substituting parts of aerobic training (AT) by resistance training (RT) on metabolic syndrome (MetS) factors. MetS patients (aged 56 ± 7 years; body mass index 33 ± 5 kg·m^-2 and 3.9 ± 0.8 MetS factors) were randomized to undergo 1 of the following isocaloric, 16-week long exercise programs: (i) cycling 4 bouts of 4-min at 90% of maximal heart rate (HR_max) followed by 3 sets of 12 repetitions of 3 lower limb free-weight exercises (high-intensity interval training (HIIT)+RT group; n = 33), (ii) cycling 5 bouts of 4 min at 90% of HR_max (HIIT+HIIT group; n = 33), or (iii) no exercise control group (n = 21). We measured the evolution of all 5 MetS components (z score), cardiorespiratory fitness (maximal oxygen uptake), leg strength and power (leg press 1-repetition maximum (1RM) and countermovement jump (CMJ)), fasting blood glucose (FG), fasting insulin, and insulin resistance (homeostasis model assessment 2). Both training groups improved maximal oxygen uptake similarly (170 ± 310 and 190 ± 210 mL O₂·min^-1; P < 0.001) and z score (-0.12 ± 0.29 and -0.12 ± 0.31 for HIIT+RT and HIIT+HIIT, respectively; P < 0.02). However, only HIIT+RT improved CMJ (P = 0.002) and leg press 1RM above the HIIT+HIIT group (21% vs 6%; P < 0.001). Furthermore, FG only decreased in the HIIT+RT group (5%; P = 0.026, time × group). Our findings suggest that substitution of part of HIIT by leg RT improves glucose control in MetS individuals. Novelty Most studies addressing the efficacy of endurance versus resistance training are not matched by energy expenditure. We found that substituting 20% of AT with RT reduces hyperglycemia in MetS individuals. Training recommendations to regain glycemic control in MetS individuals should include resistance training.

Fat metabolism and acute resistance exercise in trained women

This study investigated the effect of acute full-body resistance exercise [RE; one set of 10 repetitions at 40% 1 repetition maximum (1RM) and three sets of 10 repetitions at 65% 1RM] on subcutaneous abdominal adipose tissue (SCAAT) lipolysis and whole body substrate oxidation in young (age: 22 ± 1 yr), normal-weight and body fatness (body mass index: 20 ± 1 kg/m2; %body fat: 28.7 ± 1.4%), resistance-trained women. Microdialysis was used to measure SCAAT lipolysis at baseline, mid-RE, post-RE, and 30 min post-RE, and indirect calorimetry was used to measure whole body substrate oxidation at baseline and immediately post-RE in 13 women. Plasma concentrations of glucose, insulin, nonesterified fatty acids (NEFA), glycerol, growth hormone (GH), epinephrine (Epi), and norepinephrine (NE) were measured at baseline, mid-RE, and post-RE. Lipolysis (dialysate glycerol concentration) was elevated post-RE (baseline: 596.7 ± 82.8, post-RE: 961.4 ± 116.3 µM, P = 0.01). Energy expenditure (baseline: 1,560 ± 49; post-RE: 1,756 ± 68 kcal/day; P = 0.02) and fat oxidation (baseline: 5.64 ± 0.24; post-RE: 7.57 ± 0.41 g/h; P = 0.0003) were elevated post-RE. GH (baseline: 513.1 ± 147.4; mid-RE: 1,288.3 ± 83.9; post-RE: 1,522.8 ± 51.1 pg/ml, P = 0.000), Epi (baseline: 23.2 ± 2.7; mid-RE: 92.5 ± 16.6; post-RE: 84.5 ± 21.4 pg/ml, P = 0.000), and NE (baseline: 139.2 ± 13.6; mid-RE: 850.9 ± 155.3; post-RE: 695.3 ± 93.5 pg/ml, P = 0.000) were higher at mid-RE and post-RE. Therefore, one of the potential mechanisms behind RE-induced fat mass changes in resistance-trained women may be in part due to the accumulated effect of transient increases in SCAAT lipolysis, fat oxidation, and energy expenditure, mediated by GH, Epi, and NE release.

Acipimox Administration With Exercise Induces a Co-feedback Action of the GH, PP, and PYY on Ghrelin Associated With a Reduction of Peripheral Lipolysis in Bulimic and Healthy-Weight Czech Women: A Randomized Study

Objective: Anti-lipolytic drugs and exercise are enhancers of growth hormone (GH) secretion. Decreased circulating free fatty acids (FFA) have been proposed to exert ghrelin-GH feedback loop after administration of an anti-lipolytic longer-acting analog of nicotinic acid, Acipimox (OLB, 5-Methylpyrazine-2-carboxylic acid 4-oxide, molecular weight of 154.1 Da). OLB administration strongly suppresses plasma FFA during exercise. Neuroendocrine perturbations of the adipose tissue (AT), gut, and brain peptides may be involved in the etiopathogenesis of eating disorders including bulimia nervosa (BN) and anorexia nervosa. BN is characterized by binge eating, self-induced vomiting or excessive exercise. Approach: To test the hypothesis that treatment with OLB together with exercise vs. exercise alone would induce feedback action of GH, pancreatic polypeptide (PP), peptide tyrosine tyrosine (PYY), and leptin on ghrelin in Czech women with BN and in healthy-weight Czech women (HW). The lipolysis rate (as glycerol release) in subcutaneous abdominal AT was assessed with microdialysis. At an academic medical center, 12 BN and 12 HW (the control group) were randomized to OLB 500 mg 1 h before a single exercise bout (45 min, 2 W/kg of lean body mass [LBM]) once a week vs. identical placebo over a total of 2 weeks. Blood plasma concentrations of GH, PP, PYY, leptin, ghrelin, FFA, glycerol, and concentrations of AT interstitial glycerol were estimated during the test by RIA utilizing ¹²⁵I-labeled tracer, the electrochemiluminescence technique (ECLIA) or colorimetric kits. Results: OLB administration together with short-term exercise significantly increased plasma GH (P < 0.0001), PP (P < 0.0001), PYY, and leptin concentrations and significantly decreased plasma ghrelin (P < 0.01) concentrations in both groups, whereas short-term exercise with placebo resulted in plasma ghrelin (P < 0.05) decrease exclusively in BN. OLB administration together with short-term exercise significantly lowered local subcutaneous abdominal AT interstitial glycerol (P < 0.0001) to a greater extent in BN. Conclusion: OLB-induced suppression of plasma ghrelin concentrations together with short-term exercise and after the post-exercise recovering phase suggests a potential negative co-feedback of GH, PP, PYY, and leptin on ghrelin secretion to a greater extent in BN. Simultaneously, the exercise-induced elevation in AT interstitial glycerol leading to a higher inhibition of peripheral lipolysis by OLB in BN. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03338387.

Progressive circuit resistance training improves inflammatory biomarkers and insulin resistance in obese men

BACKGROUND

Circuit resistance training (CRT) is a time-efficient exercise modality for improving skeletal muscle and cardiovascular fitness. But the beneficial role of CRT in obese individuals is still not well understood. This study explores the reducing effects of progressive CRT on inflammatory biomarkers and cardiometabolic risk factors in obese young men.

METHODS

Thirty obese men (Body mass index (BMI): 30.67 ± 3.06; age: 23 ± 3.2 years) were divided into CRT and control groups. The CRT was performed for eight-weeks (3 times/week, 65-85% of 1 repetition maximum). Fasting blood samples were taken pre and post intervention for analyzing apelin, chemerin, serum amyloid A (SAA), C reactive protein concentrations (CRP), lipid profile, and insulin resistance index. The data were assessed by two-way repeated measures ANOVA.

RESULTS

Body mass, BMI and waist to hip ratio (WHR) were significantly decreased after training intervention (P < .05). Compared to the control group, the plasma concentrations of Chemrin (P = .038), SAA (P = .004), insulin (P < .001), insulin resistance index (P < .001), total cholesterol (P = .033), triglyceride (P < .001), and low-density lipoprotein (P = .039), were significantly mitigated in the CRT group, but high-density lipoprotein plasma levels increased in the CRT group compared to that of the control group (P = .035). There was no significant difference between two groups in apelin and CRP (P > .05). Moreover, insulin resistance was positively correlated with apelin (r = 0.56) and chemerin (r = 0.51). Also, chemerin had a positive correlation with SAA (r = 0.49), and WHR (r = 0.54).

CONCLUSION

CRT caused an improvement in inflammation and cardiometabolic risk factors in young obese men, and this improvement was accompanied by decreased insulin resistance.

Effects of Resistance Training and Protein Supplementation in Breast Cancer Survivors

PURPOSE

This study aimed to evaluate 12 wk of resistance training (RT; n = 16) and protein supplementation (RT + protein; n = 17) on muscular strength, body composition, and blood biomarkers of muscle (insulin-like growth factor 1 [IGF-1]), fat (adiponectin), and inflammation (human C-reactive protein [CRP]) in breast cancer survivors (BCS).

METHODS

Thirty-three BCS (59 ± 8 yr) were measured pre- and posttraining for one-repetition maximum (1-RM) muscular strength (chest press and leg extension), body composition (lean mass [LM] and fat mass [FM]) via dual-energy x-ray absorptiometry, and serum concentrations of IGF-1, adiponectin, and CRP. RT consisted of 2 d·wk using 10 exercises for two sets of 10-12 repetitions and a third set to failure at ~65%-85% of 1-RM. RT + protein consumed 20 g of protein twice a day. ANOVA was used for analyses. Significance was set at P ≤ 0.05.

RESULTS

Average RT intensity was 65%-81% of 1-RM and was not different between RT and RT + protein. There were no group-time interactions for strength, LM, FM, and biomarkers. Both groups significantly increased upper (+31 ± 18 kg) and lower (+19 ± 12 kg) body strength, LM (+0.9 ± 1.0 kg) and decreased FM (-0.5 ± 1.2 kg), and percent body fat (-1.0% ± 1.2%). Serum levels of IGF-1 significantly increased from baseline to 12 wk in both RT (102 ± 34 to 115 ± 33 ng·mL) and RT + protein (110 ± 40 to 119 ± 37 ng·mL); adiponectin and CRP did not change.

CONCLUSIONS

Twelve weeks of RT at 65%-81% of 1-RM, 2 d·wk in BCS, was well tolerated and significantly improved strength, body composition, and IGF-1. Supplemental protein (40 g·d) did not induce a change in any variable. However, on the basis of food logs, reductions in total calories and dietary protein intake from whole foods resulted in only a net protein increase of 17 g·d for RT + protein, which may have influenced the results.

Increased Triacylglycerol Lipase Activity in Adipose Tissue of Lean and Obese Men During Endurance Exercise

CONTEXT

Although there is increasing information on the mechanism of lipolysis in adipose tissue, the effect of exercise on individual factors of lipolysis is less well understood.

OBJECTIVE

We compared changes in adipose-tissue triacylglycerol lipase activity and gene expression of adipose triacylglycerol lipase (ATGL), hormone-sensitive lipase (HSL), monoacylglycerol lipase, perilipin 1, and comparative gene identification 58 (CGI-58) during exercise between lean and obese men.

DESIGN AND PARTICIPANTS

Seven lean and nine obese men cycled for 30 minutes at a heart rate of 130 to 140 beats per minute. At baseline and 5, 10, 20, and 30 minutes of exercise, we sampled subcutaneous adipose tissue for triacylglycerol lipase activity and mRNA determination, and blood for glycerol, nonesterified fatty acid, glucose, lactate, insulin, and catecholamine determination.

SETTING

The study was conducted at a university research unit.

RESULTS

Triacylglycerol lipase activity increased at 10 minutes of exercise in the lean men and returned to baseline at 20 and 30 minutes. In the obese men, it was higher than baseline at 10, 20, and 30 minutes and higher than the corresponding values in the lean men at 20 and 30 minutes. No changes in mRNA levels were found during exercise, but the obese men had lower mRNA levels of ATGL, HSL, and CGI-58 compared with the lean men.

CONCLUSION

Our findings suggest different patterns of lipolytic stimulation during endurance exercise between lean and obese men. Differences in lipolytic rates seem to be due to differences in protein amount or activity, not mRNA levels.

Postprandial hormone response after endurance or resistance exercise in obese women

Physiological changes with endurance exercise (EE) and resistance training (RT) are likely influenced by the metabolic and hormonal response to each exercise bout, but may be blunted in obese individuals. To compare acute effects of EE, RT, and a control upon hormonal changes in obese women, sedentary, obese women (n=12) participated in a randomised crossover-design study on 3 occasions. EE consisted of treadmill walking (65% VO2max for 1 h). A total-body RT workout consisted of 3 sets of 10 repetitions, 90 s rest for 8 exercises at 90-100% of 10RM. Blood samples were taken 30 min before exercise (0 min), 30 min post-exercise (120 min), and again at 200, 280, and 520 min to assess changes in growth hormone (GH), cortisol, and insulin throughout the postprandial period. A 20 kcal/kg fat-free mass (FFM) meal was given after post-exercise blood sample. There was a main effect of condition for GH ΔAUC (change in area under the curve), with both RT and EE significantly different from the control (RT = 463.0±138.2; EE = 243.2±131.6; Control = -90.4±157.6 ng/ml * 400 min, P<0.02, Control vs EE, effect size (ES) = 2.3; Control vs RT, ES=3.7; EE vs RT, ES=1.6). There were no condition effects for cortisol or insulin ΔAUC. There were no significant time-by-condition interactions for any variables. In obese women, circulating GH concentration is enhanced in the postprandial state following a single bout of either EE or RT, with the GH response being more robust than cortisol or insulin. As circulating GH has shown to be reduced in obesity, the present observations could be considered beneficial, particularly alongside the absence of enhanced cortisol level after exercise.

Can Resistance Exercise Alter Irisin Levels and Expression Profiles of FNDC5 and UCP1 in Rats?

Background

Irisin is a new myokine secreted from the skeletal muscle and appears to affect the metabolism of adipose tissue.

Objectives

The mechanisms of cellular and molecular identification by which exercise training exerts its benefits remain unclear and are under investigation.

Methods

We examined the effect of 8-week resistance exercise on plasma irisin levels and expression profiles of muscle FNDC5 and subcutaneous adipose tissue UCP1 in male rats. Sixteen adult male rats were divided into two groups, control (n = 8) and exercise training (n = 8) groups. The training group received exercise for 3 days/week on a specific ladder (120 cm height) with a carrying load of 50% of body weight, which was attached to their tails.

Results

The weight of the load was gradually increased during the training sessions, ultimately reaching 200% of the body weight of rats in the final week. There were three sets of five repetitions with a 3-min rest between each set of exercise sessions and 1 minute between repetitions. Plasma irisin levels and relative mRNA expression of the genes UCP1 and FNDC5 were assessed. The results demonstrated a significant increase in the irisin levels after 8 weeks of resistance exercise (P < 0.001, t = 4.48). The relative expression of FNDC5 (P < 0.001, t = 6.18) and UCP1 genes (P < 0.001, t = 13.91) was also significantly increased.

Conclusions

Therefore, we can conclude from this study that resistance exercise may improve body composition possibly through increased thermogenesis in white adipose tissue through the secretion of irisin.

The Effect of Casein Protein Prior to Sleep on Fat Metabolism in Obese Men

We have previously shown that ingesting protein at night before sleep is either beneficial or non-detrimental to metabolism, health, and body composition in obese women. However, the overnight protein-induced lipolytic actions and mechanism for improved metabolism and body composition have not been fully established. Therefore, in a crossover design, twelve obese men (age, 27.0 ± 2.2 years) were randomly assigned to ingest (within 30 min of sleep) casein protein (CAS, 120 kcal) or a non-nutritive placebo (PLA) before going to sleep. Markers of fat metabolism (lipolysis, substrate utilization, growth hormone), insulin, glucose, resting energy expenditure (REE), and appetite (questionnaire and ghrelin) were measured. During sleep and the next morning, interstitial glycerol from the subcutaneous abdominal adipose tissue (SCAAT) was measured using microdialysis. There were no differences in SCAAT glycerol (overnight: CAS, 177.4 ± 26.7; PLA, 183.8 ± 20.2 μmol/L; morning: CAS, 171.6 ± 19.1; PLA, 161.5 ± 18.6 μmol/L), substrate utilization, REE, or any blood markers between CAS and PLA. Desire to eat was greater for CAS compared to baseline (p = 0.03), but not different from PLA (baseline: 39 ± 6, CAS: 62 ± 8, PLA: 55 ± 5 mm). CAS consumption before sleep did not affect fat or glucose metabolism, REE, or suppress appetite in hyperinsulemic obese men. CAS may be consumed before sleep without impeding overnight or morning fat metabolism in young, obese men.

A microdialysis method to measure in vivo hydrogen peroxide and superoxide in various rodent tissues

Reactive oxygen species (ROS) play a critical role in cell signaling and disease pathogenesis. Despite their biological importance, assessment of ROS often involves measurement of indirect byproducts or measurement of ROS from excised tissue. Herein, we describe a microdialysis technique that utilizes the Amplex Ultrared assay to directly measure hydrogen peroxide (H₂O₂) and superoxide in tissue of living, anesthetized rats and mice. We demonstrate the application of this methodology in the penis, adipose tissue, skeletal muscle, kidney, and liver. We provide data demonstrating the impact of important methodological considerations such as membrane length, perfusion rate, and time-dependence upon probe insertion. In this report, we provide a complete list of equipment, troubleshooting tips, and suggestions for implementing this technique in a new system. The data herein demonstrate the feasibility of measuring both in vivo H₂O₂ and superoxide in the extracellular environment of various rodent tissues, providing a technique with potential application to a vast array of disease states which are subject to oxidative stress.

Effects of a progressive resistance exercise program with high-speed component on the physical function of older women with sarcopenic obesity: a randomized controlled trial

Background

Sarcopenic obesity is associated with disability in older people, especially in women. Resistance exercises are recommended for this population, but their efficacy is not clear.

Objective

To evaluate the effects of a progressive resistance exercise program with high-speed component on the physical function of older women with sarcopenic obesity.

Method

Twenty-eight women 65 to 80 years old, with a body mass index ≥30kg/m² and handgrip strength ≤21kg were randomly allocated to two groups. The experimental group underwent a 10-week resistance exercise program designed to improve strength, power, and endurance of lower-limb muscles, with open chain and closed chain exercises. The control group had their health status monitored through telephone calls. The primary outcomes were lower limb muscle performance measured by knee extensor strength, power and fatigue by isokinetic dynamometry, and mobility measured by the Short Physical Performance Battery and by gait velocity. The secondary outcome was health-related quality of life assessed by the SF-36 Questionnaire.

Results

The average rate of adherence was 85%, with few mild adverse effects. There were no significant between-group differences for any of the outcomes.

Conclusion

In this study, a progressive resistance exercise program with high-speed component was not effective for improving the physical function of older women with sarcopenic obesity.

The influence of nighttime feeding of carbohydrate or protein combined with exercise training on appetite and cardiometabolic risk in young obese women

Single macronutrient intake prior to sleep reduces appetite but may negatively impact insulin sensitivity in sedentary obese women. The present study examined the additive impact of nighttime feeding of whey (WH), casein (CAS), or carbohydrate (CHO) combined with exercise training on appetite, cardiometabolic health, and strength in obese women. Thirty-seven sedentary obese women (WH, n = 13, body mass index (BMI) 34.4 ± 1.3 kg/m(2); CAS, n = 14, BMI 36.5 ± 1.8 kg/m(2); CHO, n = 10, BMI 33.1 ± 1.7 kg/m(2)) consumed WH, CAS, or CHO (140-150 kcal/serving), every night of the week, within 30 min of sleep, for 4 weeks. Supervised exercise training (2 days of resistance training and 1 day of high-intensity interval training) was completed 3 days per week. Pre- and post-testing measurements included appetite ratings, mood state, resting metabolic rate, fasting lipids, glucose, and hormonal responses (insulin, leptin, adiponectin, hs-CRP, IGF-1, and cortisol), body composition, and strength. Nighttime intake of CAS significantly (p < 0.05) increased morning satiety (pretraining, 25 ± 5; post-training 41 ± 6) more than WH (pretraining, 34 ± 5; post-training, 35 ± 6) or CHO (pre 40 ± 8, post 43 ± 7). Exercise training increased lean mass and strength, decreased body fat, and improved mood state in all groups. No other differences were noted. Nighttime feeding of CAS combined with exercise training increased morning satiety more than WH or CHO. Nighttime feeding for 4 weeks did not impact insulin sensitivity (assessed via homeostatic model assessment of insulin resistance) when combined with exercise training in obese women. ClinicalTrial.gov: NCT01830946.

Protein-Pacing from Food or Supplementation Improves Physical Performance in Overweight Men and Women: The PRISE 2 Study

We recently reported that protein-pacing (P; six meals/day @ 1.4 g/kg body weight (BW), three of which included whey protein (WP) supplementation) combined with a multi-mode fitness program consisting of resistance, interval sprint, stretching, and endurance exercise training (RISE) improves body composition in overweight individuals. The purpose of this study was to extend these findings and determine whether protein-pacing with only food protein (FP) is comparable to WP supplementation during RISE training on physical performance outcomes in overweight/obese individuals. Thirty weight-matched volunteers were prescribed RISE training and a P diet derived from either whey protein supplementation (WP, n = 15) or food protein sources (FP, n = 15) for 16 weeks. Twenty-one participants completed the intervention (WP, n = 9; FP, n = 12). Measures of body composition and physical performance were significantly improved in both groups (p < 0.05), with no effect of protein source. Likewise, markers of cardiometabolic disease risk (e.g., LDL (low-density lipoprotein) cholesterol, glucose, insulin, adiponectin, systolic blood pressure) were significantly improved (p < 0.05) to a similar extent in both groups. These results demonstrate that both whey protein and food protein sources combined with multimodal RISE training are equally effective at improving physical performance and cardiometabolic health in obese individuals.

LIMIAR ANAERÓBIO A PARTIR DA PSE EM EXERCÍCIO RESISTIDO POR MODELOS MATEMÁTICOS

Introdução: O limiar anaeróbio é comumente identificado em exercícios cíclicos, contudo, também pode ser determinado no exercício resistido (ER) por diferentes métodos, e assim, estimar a carga de trabalho relacionada ao estresse metabólico. No entanto, sua identificação a partir de outros métodos como o modelo matemático da DMáx e principalmente por variáveis mais acessíveis, como a percepção subjetiva de esforço (PSE), ainda não foi analisada. Objetivo: Comparar o limiar de lactato (LL) identificado pelo método de inspeção visual (LLIV) com o método da DMáx aplicado nas respostas do lactato (LLDMáx) e da PSE (PSE12/13 e PSEDMáx) durante exercício resistido incremental. Métodos: Dez praticantes de ER (24,8 ± 3,0 anos) foram submetidos ao teste de uma repetição máxima (1-RM) e a um teste incremental no leg-press, obtendo-se a PSE e o lactato em cada estágio. Resultados: Foi possível identificar o limiar anaeróbio por todos os métodos, entre 30% a 40% de 1-RM. As cargas absolutas, concentrações de lactato sanguíneo e PSE não foram diferentes entre os métodos empregados e apresentaram boa concordância entre si. Conclusão: É possível identificar o limiar anaeróbio tanto por inspeção visual quanto pelo modelo matemático de DMáx para o lactato e PSE, ampliando as possibilidades de determinação do limiar anaeróbio no exercício resistido por métodos de baixo custo e não invasivos.

Effects of concurrent training on oxidative stress and insulin resistance in obese individuals

Obesity is associated with insulin resistance (IR) and increased oxidative stress. Thus, the present study aimed to evaluate anthropometric parameters, IR, and oxidative stress in obese individuals subjected to two types of concurrent training at the same intensity but differing in frequency. Accordingly, 25 individuals were divided into two groups: concurrent training 1 (CT1) (5 d/wk) and concurrent training 2 (CT2) (3 d/wk), both with moderate intensity. Anthropometric parameters, IR, and oxidative stress were analyzed before and after 26 sessions of training. Both groups had reduced body weight and body mass index (P < 0.05), but only CT1 showed lower body fat percentage and increased basal metabolic rate (P < 0.05). Moreover, CT1 had increased HOMA-IR and decreased protein damage (carbonyl level), and CT2 had decreased HOMA-IR and increased lipid peroxidation (TBARS level) (P < 0.05). On the other hand, both training protocols reduced the GPx activity. It can be concluded that both types of concurrent training could be an alternative for lowering body weight and BMI. Also, it was observed that concurrent training, depending on the frequency, can contribute to reducing body fat, oxidative damage (protein oxidation), and IR but can induce oxidative damage to lipids. More studies are needed to elucidate the mechanisms involved.

Fatty Acids, Obesity and Insulin Resistance

OBJECTIVE

Although elevated free fatty acid (FFA) levels in obesity have been considered to be of importance for insulin resistance, a recent meta-analysis suggested normal FFA levels in obese subjects. We investigated fasting circulating FFA and glycerol levels in a large cohort of non-obese and obese subjects.

METHODS

Subjects recruited for a study on obesity genetics were investigated in the morning after an overnight fast (n = 3,888). Serum FFA (n = 3,306), plasma glycerol (n = 3,776), and insulin sensitivity index (HOMA-IR,n = 3,469) were determined. Obesity was defined as BMI ≥ 30 kg/m 2 and insulin resistance as HOMA-IR ≥ 2.21.

RESULTS

In obese subjects, circulating FFA and glycerol levels were higher than in non-obese individuals (by 26% and 47%, respectively; both p < 0.0001). Similar results were obtained if only men, women or medication-free subjects were investigated. Insulin resistance and type 2 diabetes were associated with a further minor increase in FFA/glycerol among obese subjects. When comparing insulin-sensitive non-obese with insulin-sensitive or -resistant obese individuals, FFA and glycerol were 21–29% and 43–49% higher in obese individuals, respectively.

CONCLUSION

Circulating FFA and glycerol levels are markedly elevated in obesity but only marginally influenced by insulin resistance and type 2 diabetes. Whether these differences persist during diurnal variations in circulating FFA/glycerol, remains to be established

Positive affect and age as predictors of exercise compliance

Physical exercise is linked to individuals whose affect profiles are invariably positive and it induces anti-apoptotic and anti-excitotoxic effects, buttressing blood–brain barrier intactness in both healthy individuals and those suffering from disorders accompanying overweight and obesity. In this regard, exercise offers a unique non-pharmacologic, non-invasive intervention that incorporates different regimes, whether dynamic or static, endurance, or resistance. In this brief report we present a self-reported study carried out on an adolescent and adult population (N = 280, 144 males and 136 females), which indicated that the propensity and compliance for exercise, measured as the “Archer ratio”, was predicted by a positive affect. This association is discussed from the perspective of health, well-being, affect dimensions, and age.

Osteosarcopenic obesity: the role of bone, muscle, and fat on health

Osteopenia/osteoporosis, sarcopenia, and obesity are commonly observed in the process of aging, and recent evidence suggests a potential interconnection of these syndromes with common pathophysiology. The term osteosarcopenic obesity has been coined to describe the concurrent appearance of obesity in individuals with low bone and muscle mass. Although our understanding of osteosarcopenic obesity's etiology, prevalence, and consequences is extremely limited, it is reasonable to infer its negative impact in a population that is aging in an obesogenic environment. It is likely that these individuals will present with poorer clinical outcomes caused by the cascade of metabolic abnormalities associated with these changes in body composition. Clinical outcomes include but are not limited to increased risk of fractures, impaired functional status (including activities of daily living), physical disability, insulin resistance, increased risk of infections, increased length of hospital stay, and reduced survival. These health outcomes are likely to be worse when compared to individuals with obesity, sarcopenia, or osteopenia/osteoporosis alone. Interventions that utilize resistance training exercise in conjunction with increased protein intake appear to be promising in their ability to counteract osteosarcopenic obesity.

Effects of acute resistance exercise on muscle damage and perceptual measures between men who are lean and obese

The purpose of this investigation was to assess indices of muscle damage and psychological stress between young, untrained, lean, and obese men. Using a between-subject design, 19 young men (9 lean men [age, 20.1 ± 2.1 years; body mass, 71.7 ± 5.8 kg; height, 177.8 ± 8.7 cm; body fat (BF), 14.7 ± 3.5%], 5 World Health Organization [WHO] class 1 obese men [age, 21.6 ± 2.5 years; body mass, 97.8 ± 8.6 kg; height, 176.3 ± 3.7 cm; BF, 34.7 ± 3.0%], and 5 WHO class 2 or 3 men [age, 20.0 ± 1.4 years; body mass, 120.8 ± 10.5 kg; height, 177.7 ± 5.2 cm; BF, 40.5 ± 5.8%]) volunteered and completed an acute resistance exercise (RE) protocol (6 exercises performed for 3 sets of 10 repetitions at an intensity of 85-95% of a 10 repetition maximum). Plasma myoglobin and serum creatine kinase were obtained before and immediately after exercise, and in recovery (at +110 minutes and +24 hours). Perceptual measures including rating of perceived exertion, pain and soreness, fatigue, and general soreness were assessed at different time points (during exercise for rating of perceived exertion, and for the fatigue and soreness measures before, immediately after, and at 24 hours of recovery from exercise). The primary findings of this investigation were that lean and obese, sedentary, young men do not significantly differ from each other in terms of indirect, humoral measures of muscle damage, or perceptual scales in response to a moderate-intensity acute RE bout, despite using significantly more exercise volume relative to fat mass (FM). We conclude that excess FM during daily activities of life provides a protective effect for muscle damage. When strength training individuals who are obese, practitioners should be aware of how excess FM affects muscle damage and total volume. But these considerations do not preclude individuals who are obese from using well-designed RE workouts which use free-weight, multijoint movements that stimulate all of the major muscle groups.

Timed-daily ingestion of whey protein and exercise training reduces visceral adipose tissue mass and improves insulin resistance: the PRISE study

The present study examined the effects of timed ingestion of supplemental protein (20-g servings of whey protein, 3×/day), added to the habitual diet of free-living overweight/obese adults and subsequently randomized to either whey protein only (P; n = 24), whey protein and resistance exercise (P + RT; n = 27), or a whey protein and multimode exercise training program [protein and resistance exercise, intervals, stretching/yoga/Pilates, endurance exercise (PRISE); n = 28]. Total and regional body composition and visceral adipose tissue (VAT) mass (dual-energy X-ray absorptiometry), insulin sensitivity [homeostasis model assessment-estimated insulin resistance (HOMA-IR)], plasma lipids and adipokines, and feelings of hunger and satiety (visual analog scales) were measured before and after the 16-wk intervention. All groups lost body weight, fat mass (FM), and abdominal fat; however, PRISE lost significantly (P < 0.01) more body weight (3.3 ± 0.7 vs. 1.1 ± 0.7 kg, P + RT) and FM (2.8 ± 0.7 vs. 0.9 ± 0.5 kg, P + RT) and gained (P < 0.05) a greater percentage of lean body mass (2 ± 0.5 vs. 0.9 ± 0.3 and 0.6 ± 0.4%, P + RT and P, respectively). Only P + RT (0.1 ± 0.04 kg) and PRISE (0.21 ± 0.07 kg) lost VAT mass (P < 0.05). Fasting glucose decreased only in P + RT (5.1 ± 2.5 mg/dl) and PRISE (15.3 ± 2.1 mg/dl), with the greatest decline occurring in PRISE (P < 0.05). Similarly, HOMA-IR improved (0.6 ± 0.3, 0.6 ± 0.4 units), and leptin decreased (4.7 ± 2.2, 4.7 ± 3.1 ng/dl), and adiponectin increased (3.8 ± 1.1, 2.4 ± 1.1 μg/ml) only in P + RT and PRISE, respectively, with no change in P. In conclusion, we find evidence to support exercise training and timed ingestion of whey protein added to the habitual diet of free-living overweight/obese adults, independent of caloric restriction on total and regional body fat distribution, insulin resistance, and adipokines.

Obesity, growth hormone and exercise

Growth hormone (GH) is regulated, suppressed and stimulated by numerous physiological stimuli. However, it is believed that obesity disrupts the physiological and pathological factors that regulate, suppress or stimulate GH release. Pulsatile GH has been potently stimulated in healthy subjects by both aerobic and resistance exercise of the right intensity and duration. GH modulates fuel metabolism, reduces total fat mass and abdominal fat mass, and could be a potent stimulus of lipolysis when administered to obese individuals exogenously. Only pulsatile GH has been shown to augment adipose tissue lipolysis and, therefore, increasing pulsatile GH response may be a therapeutic target. This review discusses the factors that cause secretion of GH, how obesity may alter GH secretion and how both aerobic and resistance exercise stimulates GH, as well as how exercise of a specific intensity may be used as a stimulus for GH release in individuals who are obese. Only five prior studies have investigated exercise as a stimulus of endogenous GH in individuals who are obese. Based on prior literature, resistance exercise may provide a therapeutic target for releasing endogenous GH in individuals who are obese if specific exercise programme variables are utilized. Biological activity of GH indicates that this may be an important precursor to beneficial changes in body fat and lean tissue mass in obese individuals. However, additional research is needed including what molecular GH variants are acutely released and involved at target tissues as a result of different exercise stimuli and what specific exercise programme variables may serve to stimulate GH in individuals who are obese.

Lift weights to fight overweight

Although resistance training (RT) has long been accepted as a means for developing and maintaining muscular strength, endurance, power and muscle mass, its beneficial relationship with health factors and chronic disease has only recently been recognized in the scientific literature. Prior to 1990, resistance training was not a part of the recommended guidelines for exercise training and rehabilitation for either the American Heart Association or the American College of Sports Medicine (ACSM). In 1990, the ACSM recognized resistance training as a significant component of a comprehensive fitness programme for healthy adults of all ages, a position subsequently confirmed few years after. At present, even though interest in clinical applications of RT is increasing, there are still some concerns, among physicians, about the use of this exercise methodology in weight control programmes. This review aims to explore the metabolic effects of RT and its efficacy and feasibility in overweight subjects.

Effect of exercise on abdominal fat loss in men and women with and without type 2 diabetes

OBJECTIVE

To examine the effect of exercise on abdominal adipose tissue in adults with and without type 2 diabetes mellitus (T2DM).

DESIGN

Post hoc analysis of two randomised controlled trials.

SETTING

Outpatient secondary prevention programme in Baltimore, Maryland, USA.

PARTICIPANTS

97 men and women with prehypertension, stage 1 or medically controlled hypertension. 49% of the sample was also diagnosed with T2DM.

INTERVENTION

All participants completed a 26-week (6.5 months) supervised aerobic and resistance exercise programme following American College of Sports Medicine guidelines.

PRIMARY AND SECONDARY OUTCOME MEASURES

The main outcomes in this post hoc analysis were total abdominal adipose tissue (TAT), subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) measured by MRI. Secondary outcomes were to determine whether the magnitude of abdominal fat change differed by diabetes status in men and women and to identify the predictors of change in abdominal fat distribution with exercise.

RESULTS

Overall, participants (mean age 61±6 years; 45% women) significantly improved peak oxygen uptake by 15% (p<0.01) and reduced weight by 2% (p<0.01). No change in SAT was observed after training. The reduction in VAT following exercise was attenuated in participants with T2DM (-3%) compared with participants who were non-T2DM (-18%, p<0.001 for the difference in change). The magnitude of VAT loss was associated with a decrease in body weight (r=0.50, p<0.001). After adjustment for weight change using regression analysis, diabetes status remained an independent predictor of the change in VAT.

CONCLUSIONS

Although participants with and without T2DM attained an exercise training effect as evidenced by increased fitness, VAT was unchanged in T2DM compared to those without T2DM, suggesting that these individuals may be resistant to this important benefit of exercise. The strategies for reducing cardiovascular disease risk in T2DM may be most effective when they include a weight loss component.

CLINICAL TRIALS REGISTRATION

Clinicaltrials.gov Registry NCT00212303.

Insulin-mediated suppression of lipolysis in adipose tissue and skeletal muscle of obese type 2 diabetic men and men with normal glucose tolerance

AIMS/HYPOTHESIS

Impaired regulation of lipolysis and accumulation of lipid intermediates may contribute to obesity-related insulin resistance and type 2 diabetes mellitus. We investigated insulin-mediated suppression of lipolysis in abdominal subcutaneous adipose tissue (AT) and skeletal muscle (SM) of obese men with normal glucose tolerance (NGT) and obese type 2 diabetic men.

METHODS

Eleven NGT men and nine long-term diagnosed type 2 diabetic men (7 ± 1 years), matched for age (58 ± 2 vs 62 ± 2 years), BMI (31.4 ± 0.6 vs 30.5 ± 0.6 kg/m(2)) and [Formula: see text] (28.9 ± 1.5 vs 29.5 ± 2.4 ml kg(-1) min(-1)) participated in this study. Interstitial glycerol concentrations in AT and SM were assessed using microdialysis during a 1 h basal period and a 6 h stepwise hyperinsulinaemic-euglycaemic clamp (8, 20 and 40 mU m(-2) min(-1)). AT and SM biopsies were collected to investigate underlying mechanisms.

RESULTS

Hyperinsulinaemia suppressed interstitial SM glycerol concentrations less in men with type 2 diabetes (-7 ± 6%, -13 ± 9% and -27 ± 9%) compared with men with NGT (-21 ± 7%, -38 ± 8% and -53 ± 8%) (p = 0.014). This was accompanied by increased circulating fatty acid and glycerol concentrations, a lower glucose infusion rate (21.8 ± 3.1 vs 30.5 ± 2.0 μmol kg body weight(-1) min(-1); p < 0.05), higher hormone-sensitive lipase (HSL) serine 660 phosphorylation, increased saturated diacylglycerol (DAG) lipid species in the muscle membrane and increased protein kinase C (PKC) activation in type 2 diabetic men vs men with NGT. No significant differences in insulin-mediated reduction in AT interstitial glycerol were observed between groups.

CONCLUSIONS/INTERPRETATION

Our results suggest that a blunted insulin-mediated suppression of SM lipolysis may promote the accumulation of membrane saturated DAG, aggravating insulin resistance, at least partly mediated by PKC. This may represent an important mechanism involved in the progression of insulin resistance towards type 2 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01680133.

The effects of pre- and post-exercise consumption of multi-ingredient performance supplements on cardiovascular health and body fat in trained men after six weeks of resistance training: a stratified, randomized, double-blind study

Background

The cardiovascular (CV) and metabolic health benefits or risks associated with consumption of multi-ingredient performance supplements (MIPS) in conjunction with periodized resistance training (RT) in resistance-trained men are unknown. This population is a major target audience for performance supplements, and therefore, the purpose of this study was to investigate the combined effect of RT and commercially available pre- and post-exercise performance supplements on CV health and body fat in resistance-trained men.

Methods

Twenty-four resistance-trained men completed six weeks (three times/week) of periodized RT while either ingesting SHOT 15-min pre-exercise and SYN immediately post-exercise (multi-ingredient performance supplement group: MIPS) or an isocaloric maltodextrin placebo 15-min pre-exercise and immediately post-exercise (Placebo group). Before and after six weeks of RT and supplementation, resting heart rate (HR), blood pressure (BP), total body fat, android fat, gynoid fat, fat-free mass (FFM) and fasting blood measures of glucose, lipids, nitrate/nitrite (NOx), cortisol and high sensitivity C-reactive protein (hs-CRP) were measured. Statistical analysis was conducted using a one-way ANOVA for baseline differences and a 2 × 2 (group × time) repeated measures ANOVA and Tukey post-hoc tests where appropriate. Significance was set at p < 0.05.

Results

There was no group × time interaction for HR, BP, blood glucose, lipids, NOx, hs-CRP, cortisol concentrations or body fat. However, there was a time effect where significant decreases in body fat (mean ± SD; MIPS: -1.2 ± 1.2%; Placebo: -0.9 ± 1.1%), android fat (MIPS: -1.8 ± 2.1%; Placebo: -1.6 ± 2.0%), and gynoid fat (MIPS: -1.3 ± 1.6%; Placebo: -1.0 ± 1.4%) for both groups were observed. FFM increased in both groups, and a group × time interaction was observed with MIPS increasing significantly more than the Placebo group (4.2% vs. 1.9%).

Conclusions

Six weeks of MIPS ingestion and periodized RT does not alter CV health parameters or blood indices of health or body fat more than a Placebo treatment in healthy, resistance-trained men. However, MIPS significantly increased FFM more than Placebo.

High-Intensity Interval Resistance Training (HIRT) influences resting energy expenditure and respiratory ratio in non-dieting individuals

BACKGROUND

The benefits of exercise are well established but one major barrier for many is time. It has been proposed that short period resistance training (RT) could play a role in weight control by increasing resting energy expenditure (REE) but the effects of different kinds of RT has not been widely reported.

METHODS

We tested the acute effects of high-intensity interval resistance training (HIRT) vs. traditional resistance training (TT) on REE and respiratory ratio (RR) at 22 hours post-exercise. In two separate sessions, seventeen trained males carried out HIRT and TT protocols. The HIRT technique consists of: 6 repetitions, 20 seconds rest, 2/3 repetitions, 20 secs rest, 2/3 repetitions with 2'30″ rest between sets, three exercises for a total of 7 sets. TT consisted of eight exercises of 4 sets of 8-12 repetitions with one/two minutes rest with a total amount of 32 sets. We measured basal REE and RR (TT0 and HIRT0) and 22 hours after the training session (TT22 and HIRT22).

RESULTS

HIRT showed a greater significant increase (p < 0.001) in REE at 22 hours compared to TT (HIRT22 2362 ± 118 Kcal/d vs TT22 1999 ± 88 Kcal/d). RR at HIRT22 was significantly lower (0.798 ± 0.010) compared to both HIRT0 (0.827 ± 0.006) and TT22 (0.822 ± 0.008).

CONCLUSIONS

Our data suggest that shorter HIRT sessions may increase REE after exercise to a greater extent than TT and may reduce RR hence improving fat oxidation. The shorter exercise time commitment may help to reduce one major barrier to exercise.

An overview of the contribution of fatness and fitness factors, and the role of exercise, in the formation of health status for individuals who are overweight

Over the last half century there has been an epidemic of diminished health status induced by what seems as a concurrent rise in a population of individuals that are overfat. During the past few decades, the use of exercise has become a staple in the prevention and treatment options for the retarding the development of health issues pertaining to individuals who are overweight, overfatness or experience obesity. However, there are few studies and reviews look at the global issues surrounding the metabolic and hormone consequences of overfatness and the interaction of exercise with adiposity in humans developing the health status for the individual. This review offers an insight into our current understanding of health issues pertaining to metabolic and hormonal disruption related to overfatness and the treatment effect that exercise, especially resistance exercise, can have on impacting the health status, and overall well-being, for individuals who are overfat, regardless of body compositional changes leading toward a lessening of diseased state, and eventually a return to a normal health status for the individual.

Effects of resistance exercise and obesity level on ghrelin and cortisol in men

Resistance exercise (RE) is increasingly recommended by health organizations as a weight management tool. The purpose of this study was to examine the effects of an acute high-volume, whole-body RE protocol on the glucoregulatory and ghrelin response in sedentary obese and lean men. Five World Health Organization (WHO) class 1 obese (body mass index [BMI], 30.00-34.99) (age, 21.6 ± 2.5 years; height, 176.3 ± 3.7 cm; body mass, 97.8 ± 8.58 kg; body fat, 34.7% ± 2.95%), 5 WHO 2 (BMI, 35-39.99)/WHO 3 (BMI, ≥40) obese (age, 20.0 ± 1.4 years; height, 177.7 ± 5.15 cm; body mass, 120.8 ± 10.49 kg; body fat, 40.5% ± 5.82 %), and 9 lean men (age, 20.1 ± 2.1 years; height, 177.8 ± 8.7 cm; body mass, 71.7 ± 5.8 kg; body fat, 14.7% ± 3.54 %) completed an acute RE testing protocol (6 exercises, 3 sets of 10 repetitions at 85%-95% 10-repetition maximum with 120- and 90-second rest periods); and blood samples were collected pre-, mid-, and immediately postexercise and during recovery (+50, +70, and +110). Resistance exercise produced differences over time in cortisol, insulin, and glucose. Group differences were observed for ghrelin, with the WHO class 2/3 group having significantly greater ghrelin levels than the lean group (d = 0.28, P = .009) and the WHO class 1 group (d = 0.39, P = .002). Higher ghrelin was significantly associated with lower cortisol only in obese individuals. In addition, higher growth hormone was associated with lower ghrelin in lean individuals. Results suggest that glucoregulatory homeostasis is altered with increasing levels of obesity and that these alterations may mediate the response of cortisol and ghrelin in response to RE.

Resistance training volume, energy balance and weight management: rationale and design of a 9 month trial

The increased prevalence of obesity and the lack of treatment success both argue for the design and evaluation of strategies to prevent the development of overweight and obesity. To date, the role of resistance training (RT) in this regard is largely unexplored. RT may be effective for weight management as a result of increased fat-free mass (FFM), which may result in increased resting metabolic rate and increased physical activity energy expenditure. However, the literature relative to the efficacy of RT protocols recommended for healthy adults to alter the aforementioned parameters is inconsistent or inadequately evaluated. We will conduct a 9 month randomized controlled efficacy trial to compare changes in body composition (fat mass, FFM, % body fat) and energy balance in response to 2 volumes of RT (1 vs. 3 sets vs. non-exercise control) both at the completion of training (9 months) and 1 year later (body composition). This investigation will be conducted in a sample of healthy, normal and overweight, sedentary, young adult men and women; a group at high risk for development of overweight and obesity. Our results will provide information relative to the minimum volume of RT that may be associated with body weight/fat gain which may inform the development of guidelines for RT to prevent weight gain or to alter body composition.

Impaired insulin-mediated antilipolysis and lactate release in adipose tissue of upper-body obese women

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.

Immunoreactive and bioactive growth hormone responses to resistance exercise in men who are lean or obese

It has been suggested that obese individuals have a blunted growth hormone (GH) response to spontaneous and stimulated GH secretion. The present study was designed to examine the effects of a high-volume, whole body acute resistance exercise (RE) protocol on immunoreactive GH (iGH), bioactive GH (bGH), and GH-binding protein (GHBP) in sedentary lean and obese men. Nine obese (mean ± SD: 20.8 ± 2.1 yr old, 177.0 ± 4.1 cm height, 108.7 ± 15.9 kg body mass, 37.6 ± 5.29% body fat) and nine lean (20.1 ± 2.1 yr old, 177.8 ± 8.7 cm height, 71.7 ± 5.8 kg body mass, 14.7 ± 3.54% body fat) men completed an acute RE protocol (6 exercises, 3 sets of 10 repetitions at 85–95% of 10 repetitions maximum with 120- and 90-s rest periods), and blood samples were collected before, at the midpoint, and immediately after exercise and during recovery (+50, +70, and +110). In contrast to prior studies, which examined acute responses to cardiovascular exercise protocols, groups did not differ in iGH response to the exercise stimulus. However, bGH concentrations overall were significantly lower in the obese than the lean participants ( P < 0.001). Additionally, obese individuals had significantly higher GHBP concentrations ( P < 0.001). Results suggest that obese and lean sedentary men performing a high-volume, whole body acute RE protocol demonstrate similar increases in iGH. Blunted bGH and elevated GHBP concentrations are indicative of altered GH activity associated with obesity. Prior research findings of blunted iGH response may be attributable to RE protocols not equated on relative intensity or volume. These results underscore the complexity of pituitary biology and its related mechanisms and may have implications for exercise prescription in the treatment of obesity.

PAKs supplement improves immune status and body composition but not muscle strength in resistance trained individuals

Mixed formula supplements are very popular among recreational and professional weightlifters. They are usually known as PAKs and they are supposed to have a synergistic effect of their different nutrients. The purpose of this study was to determine the effects of chronic (4 weeks) PAKS supplementation in combination with strength training on body composition, immune status and performance measures in recreationally trained individuals with or without PAKs supplementation. Methods: Twelve male subjects (Placebo n = 6 and PAKs supplement n = 6) were recruited for this study. The body composition, one maximum strength repetition tests and immune status were assessed before and after 4 week supplementation. Our data showed that, 4 week PAK supplementation associated with strength exercise not was effective in change strength than compared with placebo group. However, we observed that, PAK supplement was able to improve immune status and reduced body composition when compared with placebo group. These results indicate that, a mixed formula supplement is able to improve immune status and body composition but not maximum strength in recreational strength trained subjects in a 4 weeks period.

Influence of physical exercise on neuroimmunological functioning and health: aging and stress

Chronic and acute stress, with associated pathophysiology, are implicated in a variety of disease states, with neuroimmunological dysregulation and inflammation as major hazards to health and functional sufficiency. Psychosocial stress and negative affect are linked to elevations in several inflammatory biomarkers. Immunosenescence, the deterioration of immune competence observed in the aged aspect of the life span, linked to a dramatic rise in morbidity and susceptibility to diseases with fatal outcomes, alters neuroimmunological function and is particularly marked in the neurodegenerative disorders, e.g., Parkinson's disease and diabetes. Physical exercise diminishes inflammation and elevates agents and factors involved in immunomodulatory function. Both the alleviatory effects of life-long physical activity upon multiple cancer forms and the palliative effects of physical activity for individuals afflicted by cancer offer advantages in health intervention. Chronic conditions of stress and affective dysregulation are associated with neuroimmunological insufficiency and inflammation, contributing to health risk and mortality. Physical exercise regimes have induced manifest anti-inflammatory benefits, mediated possibly by brain-derived neurotrophic factor. The epidemic proportions of metabolic disorders, obesity, and diabetes demand attention; several variants of exercise regimes have been found repeatedly to induce both prevention and improvement under both laboratory and clinical conditions. Physical exercise offers a unique non-pharmacologic intervention incorporating multiple activity regimes, e.g., endurance versus resistance exercise that may be adapted to conform to the particular demands of diagnosis, intervention and prognosis inherent to the staging of autoimmune disorders and related conditions.

Lipid mobilization in subcutaneous adipose tissue during exercise in lean and obese humans. Roles of insulin and natriuretic peptides

The aim of this study was to evaluate the relative contributions of various hormones involved in the regulation of lipid mobilization in subcutaneous adipose tissue (SCAT) during exercise and to assess the impact of obesity on this regulation. Eight lean and eight obese men performed a 60-min cycle exercise bout at 50% of their peak oxygen uptake on two occasions: during intravenous infusion of octreotide (a somatostatin analog) or physiological saline (control condition). Lipolysis in SCAT was evaluated using in situ microdialysis. One microdialysis probe was perfused with the adrenergic blockers phentolamine and propranolol while another probe was perfused with the phosphodiesterase and adenosine receptor inhibitor aminophylline. Compared with the control condition, infusion of octreotide reduced plasma insulin levels in lean (from approximately 3.5 to 0.5 microU/ml) and in obese (from approximately 9 to 2 microU/ml), blunted the exercise-induced rise in plasma GH and epinephrine levels in both groups, and enhanced the exercise-induced natriuretic peptide (NP) levels in lean but not in obese subjects. In both groups, octreotide infusion resulted in higher exercise-induced increases in dialysate glycerol concentrations in the phentolamine-containing probe while no difference in lipolytic response was found in the aminophylline-containing probe. The results suggest that insulin antilipolytic action plays a role in the regulation of lipolysis during exercise in lean as well as in obese subjects. The octreotide-induced enhancement of exercise lipolysis in lean subjects was associated with an increased exercise-induced plasma NP response. Adenosine may contribute to the inhibition of basal lipolysis in both subject groups.