Effects of exercise training intensity on nocturnal growth hormone secretion in obese adults with the metabolic syndrome

Capsinoids Increase Antioxidative Enzyme Activity and Prevent Obesity-Induced Cardiac Injury without Positively Modulating Body Fat Accumulation and Cardiac Oxidative Biomarkers

BACKGROUND/OBJECTIVES

Capsinoids are potential antioxidant agents capable of reducing oxidative damage and the resulting complications triggered by obesity. Thus, this study aimed to investigate the effects of capsinoids on adiposity and biomarkers of cardiac oxidative stress in obese rats induced by a high-fat diet.

METHODS

Male Wistar rats were exposed to a high-fat diet for 27 consecutive weeks. After the characterization of obesity (week 19), some of the obese animals began to receive capsinoids (10 mg/kg/day) by orogastric gavage. Adiposity and comorbidities were assessed. In the heart, remodeling, injury, and biomarkers of oxidative stress were determined.

RESULTS

The treatment did not reduce obesity-induced adiposity but was efficient in reducing cholesterol levels. Capsinoid treatment did not cause a difference in heart and LV mass, despite having reduced troponin I concentrations. Furthermore, capsinoids did not reduce the increase in the advanced oxidation of protein products and carbonylated proteins caused by obesity in cardiac tissue. In addition, obese rats treated with capsinoids presented high levels of malondialdehyde and greater antioxidant enzyme activity compared to untreated obese rats.

CONCLUSIONS

In conclusion, treatment with capsinoids increases antioxidative enzyme activity and prevents obesity-induced cardiac injury without positively modulating body fat accumulation and cardiac oxidative biomarkers.

The Effect of the Menstrual Cycle on Energy Intake: A Systematic Review and Meta-analysis

CONTEXT

Energy intake may differ across the menstrual cycle, with some studies identifying greater energy intake in the luteal phase (LP) compared with the follicular phase (FP) and others finding no clear differences. To date, no study has systematically synthesized the available data to draw more definite conclusions while considering any methodological inconsistencies between studies.

OBJECTIVE

The aim was to conduct a systematic review/meta-analysis in an effort to determine if there are differences in energy intake between the FP and LP.

DATA SOURCES

A systematic search strategy was developed and the search was conducted in 5 databases for studies that investigated any changes in energy intake across menstrual phases.

DATA EXTRACTION

Using Covidence, studies were identified and included if they contained individuals between the ages of 18 and 45 years, maintained an average body mass index (BMI) of 18.5-25 kg/m2, had no history of disordered eating, and included energy intake and menstrual cycle measurements in the FP and LP.

DATA ANALYSIS

Effect sizes were calculated for each study and a random-effects model was used to pool the results of each study.

RESULTS

Fifteen datasets were included consisting of 330 female participants with a mean age of 26 ± 4 years and mean BMI of 22.4 ± 2.3 kg/m2. Overall, there was a statistically significant difference (standardized mean difference = 0.69; P = .039) with increased energy intake in the LP compared with the FP (crude 168 kcal⋅d-1 average difference between phases).

CONCLUSION

Energy intake was found to be greater in the LP compared with the FP, providing insight into the effect of the menstrual cycle on energy intake. However, there were repeated methodological inconsistencies and future work should strive to utilize best practices for both energy intake measurement and menstrual phase specification.

Selective activation of IFNγ-ipilimumab enhances the therapeutic effect and safety of ipilimumab

INTRODUCTION

Immune checkpoint inhibitor therapy is a highly promising strategy for clinical treatment of cancer. Among these inhibitors, ipilimumab stands out for its ability to induce cytotoxic T cell proliferation and activation by binding to CTLA-4. However, ipilimumab also gives rise to systemic immune-related adverse effects and tumor immune evasion, limiting its effectiveness.

OBJECTIVES

We developed IFNγ-ipilimumab and confirmed that the addition of INF-γ does not alter the fundamental properties of ipilimumab.

RESULTS

IFNγ-ipilimumab can be activated by matrix metalloproteinases, thereby promoting the IFNγ signaling pathway and enhancing the cytotoxicity of T cells. In vivo studies demonstrated that IFNγ-ipilimumab enhances the therapeutic effect of ipilimumab against colorectal cancer by increasing CD8+ and CD4+ lymphocyte infiltration into the tumor area and inducing MHC-I expression in tumor cells. Mice treated with IFNγ-ipilimumab showed higher survival rates and body weight, as well as lower CD4+ and CD8+ lymphocyte activation rates in the blood and reduced organ damage.

CONCLUSION

IFNγ-ipilimumab improved the effectiveness of ipilimumab while reducing its side effects. It is likely that future immunotherapies would rely on such antibodies to activate local cancer cells or immune cells, thereby increasing the therapeutic effectiveness of cancer treatments and ensuring their safety.

Dose-response effects of exercise and caloric restriction on visceral adiposity in overweight and obese adults: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To determine and compare the dose-response effects of exercise and caloric restriction on visceral adipose tissue in overweight and obese adults, while controlling for the weekly energy deficit induced by the interventions.

METHODS

PubMed, Embase, CINAHL and Web of Science were searched for randomised controlled trials comparing exercise or caloric restriction against eucaloric controls in overweight or obese adults. The primary outcome was the change in visceral fat measured by CT or MRI. Meta-analyses and meta-regressions were performed to determine the overall effect size (ES) and the dose-dependent relationship of exercise and caloric restriction on visceral fat. Heterogeneity, risk of bias and the certainty of evidence were also assessed.

RESULTS

Forty randomised controlled trials involving 2190 participants were included. Overall, exercise (ES -0.28 (-0.37 to -0.19); p<0.001; I2=25%) and caloric restriction (ES -0.53 (-0.71 to -0.35); p<0.001; I2=33%) reduced visceral fat compared with the controls. Exercise demonstrated a dose-response effect of -0.15 ((-0.23 to -0.07); p<0.001) per 1000 calories deficit per week, whereas the effect of caloric restriction was not dose-dependent (ES 0.03 (-0.12 to 0.18); p=0.64). Most of the studies showed a moderate risk of bias.

CONCLUSIONS

These findings support the dose-dependent effects of exercise to reduce visceral fat in overweight and obese adults. Caloric restriction did not demonstrate a dose-response relationship, although this may be attributed to the smaller number of studies available for analysis, compared with exercise studies.

PROSPERO REGISTRATION NUMBER

CRD42020210096.

Resistance to obesity prevents obesity development without increasing spontaneous physical activity and not directly related to greater metabolic and oxidative capacity

There are evidence that obese-resistant animals are more physically active, due to a higher rate of lipid oxidation. Efficiency in such pathways can favor greater spontaneous physical activity and, consequently, less body fat deposition. The aim of study was characterizing the nutritional profile and spontaneous physical activity in the condition of Resistance to Obesity (OR). Wistar rats were randomized into standard diet (SD; n = 50) and high-fat diet (HFD; n = 50) groups, after obesity induction, were redistributed into Control (C), False-control (FC), Propensity to obesity (OP) and OR, and then spontaneous physical activity was evaluated. Analyzed parameters: body mass (BM), epididymal (EF), retroperitoneal (RF), visceral (VF) and respective summations (∑), adiposity index (AI), nutritional, morphological, biochemical and metabolic parameters and protein quantification. The comparison of the groups was performed by ANOVA one or two factors, with 5% significance adopted. OP and FC presented high final MC values compared to C and OR. OR had lower EF, RF, VF, ∑ and IA compared to OP. OR had similar values to C and higher HDL than FC and OP. In GTT, OR and C presented similar values and both were lower than OP in the 30 minutes. OP promoted higher values than C for glycemic AUC. OR had higher PPARγ content than C and OP, as well as levels similar to C for leptin and insulin. Spontaneous physical activity did not differ between groups. The results were not enough to show that OR animals have greater lipid oxidative capacity, as well as greater spontaneous physical activity.

Effects of Exercise in Patients with Obstructive Sleep Apnoea

Obstructive sleep apnoea (OSA) constitutes a public health problem, with various systemic consequences that can increase cardiovascular morbidity and mortality as well as increase healthcare expenditure. This review discusses the rationale and effects of using general physical exercise, oropharyngeal exercises, and respiratory muscle training as an adjunctive treatment for patients with sleep apnoea. The recommended treatment for OSA is the use of continuous positive airway pressure, which is a therapy that prevents apnoea events by keeping the airways open. In the last decade, coadjuvant treatments that aim to support weight loss (including diet and physical exercise) and oropharyngeal exercises have been proposed to lower the apnoea/hypopnoea index among patients with OSA. Based on the available evidence, health professionals could decide to incorporate these therapeutic strategies to manage patients with sleep apnoea.

Effects of Exercise on the Body Composition and Lipid Profile of Individuals with Obesity: A Systematic Review and Meta-Analysis

Background

Numerous researchers have worked to develop treatments for obesity; however, the prevalence of obesity continues to increase in many countries. Moreover, the effects of physical activity and exercise on obesity remain unclear. Therefore, it is necessary to perform a systematic review and meta-analysis to assess the relationship between exercise and obesity using mediator variables such as the mode of exercise.

Methods

Our review focuses on research tracking the effects of exercise on obesity conducted from 2007 to 2016 and available in any of three databases: Embase, PubMed, and EBSCO Academic Search Premier. The keywords used in the search were “exercise and obesity” and “exercise and obese.”

Results

The average size of the effects that exercise interventions have on body mass index (standardized mean difference [SMD], 0.533), waist circumference (SMD, 0.666), total cholesterol (SMD, 0.721), and triglyceride (TG; SMD, 0.603) were medium or larger. Exercise had greater effects on the outward appearance of obesity (body mass index, waist circumference) than on its practical factors (weight, % body fat). The effect of exercise on TG (SMD, 0.603) was larger than that on low-density lipoprotein (SMD, 0.406) and high-density lipoprotein (SMD, −0.222). Exercise duration (weeks of exercise) and intensity correlate better than exercise time (minutes per week) with a large and consistent improvement in adult obesity.

Conclusion

We suggest that individuals with obesity should exercise consistently to achieve significant improvements in their health.

Practical Guidance for Interventions in Adults with Metabolic Syndrome: Diet and Exercise vs. Changes in Body Composition

(1) Objective: to establish practical guidance for the design of future clinical trials in MS (metabolic syndrome) patients aged 18 and older, based on a systematic review of randomized clinical trials connecting diet, physical exercise and changes in body composition. (2) Method: this systematic review of randomized clinical trials (RCT) is based on the guidelines recommended by PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses). Criteria of selection: ≥18 years of age; patients diagnosed with MS; intervention programs including diet, physical exercise and/or modifications in the style of life as treatment, as well as the magnitude of changes in body composition (BC); randomized clinical trial published between 2004 and 2018. (3) Results: the multidisciplinary interventions describe major changes in BC, and the recurring pattern in these clinical trials is an energy reduction and control in the percentage of intake of macronutrients along with the performance of regularly structured exercise; the most analyzed parameter was waist circumference (88.9% of the trials), followed by body weight (85.2%), BMI (77.8%) and body fat (55.6%). (4) Conclusions: The analysis of the information here reported sheds light for the design of future clinical trials in adults with MS. The best anthropometric parameters and units of measurement to monitor the interventions are related to dietary and physical exercise interventions. A list of practical advice that is easy to implement in daily practice in consultation is here proposed in order to guarantee the best results in changes of body composition.

Physical deconditioning is the common denominator in both obese and overweight subjects with nonalcoholic steatohepatitis

BACKGROUND

Obesity and decreased physical activity mirror increasing prevalence of nonalcoholic fatty liver disease (NAFLD).

AIM

We aimed to investigate associations between aerobic fitness, anthropometrics and disease parameters in patients with nonalcoholic steatohepatitis (NASH). We hypothesised that NASH subjects have lower aerobic power and capacity than untrained, sedentary, normal subjects.

METHODS

Forty subjects (60% obese, 40% overweight) with biopsy-confirmed NASH and NAFLD activity score (NAS) ≥4 were enrolled in a clinical trial where anthropometrics, laboratories, liver fat content by MRI, activity, and aerobic fitness by cycle ergometry data were obtained.

RESULTS

NASH subjects were significantly deconditioned compared to 148 untrained, sedentary, healthy subjects from our laboratory in aerobic power (VO2peak) (NASH 16.8 ± 6.6 vs control 28.4 ± 10.6 mL/kg/min, P < 0.0001) and capacity (VO2 at lactate threshold [LT]) (NASH 8.3 ± 2.5 vs control 14.1 ± 5.9 mL/kg/min, P < 0.0001). NASH subjects' fitness was comparable to the "least fit" tertile of controls: VO2peak [NASH 16.8 ± 6.6 vs "least fit" 17.3 ± 3.3, P = 0.64]) and VO2 at LT (NASH 8.3 ± 2.5 vs "least fit" 9.3 ± 2.1, P = 0.31). Fitness was similar in obese compared to overweight subjects (adjusted for gender) and was not correlated with visceral adiposity or NAS. Engaging in dedicated cardiovascular activity correlated with higher VO2peak and VO2peak at LT.

CONCLUSIONS

Aerobic deconditioning was universally present in NASH subjects. NASH subjects' fitness was similar to our laboratory's "least fit" untrained, sedentary control subjects. Further research investigating NASH patients' ability to improve low baseline aerobic fitness is warranted.

Effect of Exercise Training on Cardiac Biomarkers in At-Risk Populations: A Systematic Review

BACKGROUND

Studies have demonstrated beneficial effects of exercise on cardiovascular disease biomarkers for healthy individuals; however, a comprehensive review regarding the effect of exercise on cardiovascular disease biomarkers in at-risk populations is lacking.

METHODS

A literature search was performed to identify studies meeting the following criteria: randomized controlled study, participants with pathology/activity limitations, biomarker outcome (total cholesterol, high-density lipoprotein, low-density lipoprotein, C-reactive protein, insulin, triglycerides, or glucose), and exercise intervention. Means and standard deviations from each biomarker were used to calculate standardized Cohen's d effect sizes with 95% confidence intervals.

RESULTS

In total, 37 articles were included. The majority (44/57; 77%) of data points demonstrated moderate to strong effects for the reduction in total cholesterol, triglycerides, and low-density lipoprotein, and elevation in high-density lipoprotein following exercise. The majority of data points demonstrated strong effects for reductions in blood glucose (24/30; 80%) and insulin (23/24; 96%) levels following exercise intervention.

CONCLUSION

Evidence is heterogeneous regarding the influence of exercise on cardiovascular disease biomarkers in at-risk patients, which does not allow a definitive conclusion. Favorable effects include reductions in triglycerides, total cholesterol, low-density lipoprotein, glucose, and insulin, and elevation in high-density lipoprotein following exercise intervention. The strongest evidence indicates that exercise is favorable for the reduction in glucose and cholesterol levels among obese patients, and reduction of insulin regardless of population.

The effect of exercise training on clinical outcomes in patients with the metabolic syndrome: a systematic review and meta-analysis

Background

Purpose: to establish if exercise training improves clinical outcomes in people with metabolic syndrome (MetS). Registered with PROSPERO international prospective register of systematic reviews (https://www.crd.york.ac.uk/PROSPERO/Identifier:CRD42017055491). Data sources: studies were identified through a MEDLINE search strategy (1985 to Jan 12, 2017), Cochrane controlled trials registry, CINAHL and SPORTDiscus. Study selection: prospective randomized or controlled trials of exercise training in humans with metabolic syndrome, lasting 12 weeks or more.

Results

We included 16 studies with 23 intervention groups; 77,000 patient-hours of exercise training. In analyses of aerobic exercise studies versus control: body mass index was significantly reduced, mean difference (MD) −0.29 (kg m⁻²) (95% CI −0.44, −0.15, p < 0.0001); body mass was significantly reduced, MD −1.16 kg (95% CI −1.83, −0.48, p = 0.0008); waist circumference was significantly reduced MD −1.37 cm (95% CI −2.02, −0.71, p < 0.0001), peak VO₂ was significantly improved MD 3.00 mL kg⁻¹ min⁻¹ (95% CI 1.92, 4.08, p < 0.000001); systolic blood pressure and diastolic blood pressure were significantly reduced, MD −2.54 mmHg (95% CI −4.34, −0.75, p = 0.006), and, MD −2.27 mmHg (95% CI −3.47, −1.06, p = 0.0002) respectively; fasting blood glucose was significantly reduced MD −0.16 mmol L⁻¹ (95% CI −0.32, −0.01, p = 0.04); triglycerides were significantly reduced MD −0.21 mmol L⁻¹ (95% CI −0.29, −0.13, p < 0.00001); and low density lipoprotein was significantly reduced MD −0.03 mmol L⁻¹ (95% CI −0.05, −0.00, p = 0.02). In analyses of combined exercise versus control: waist circumference, MD −3.80 cm (95% CI −5.65, −1.95, p < 0.0001); peak VO₂ MD 4.64 mL kg⁻¹ min⁻¹ (95% CI 2.42, 6.87, p < 0.0001); systolic blood pressure MD −3.79 mmHg (95% CI −6.18, −1.40, p = 0.002); and high density lipoprotein (HDL) MD 0.14 (95% CI 0.04, 0.25, p = 0.009) were all significantly improved. We found no significant differences between outcome measures between the two exercise interventions.

Conclusions

Exercise training improves body composition, cardiovascular, and, metabolic outcomes in people with metabolic syndrome. For some outcome measures, isolated aerobic exercise appears optimal.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0590-y) contains supplementary material, which is available to authorized users.

The impact of duration on effectiveness of exercise, the implication for periodization of training and goal setting for individuals who are overfat, a meta-analysis

Given the assumption that all methods of exercise, e.g., endurance (ET), resistance (RT), or combination of both (E+R), can induce a beneficial effect size (ES) for changes in body composition and health status of individuals who are overfat. Thus the aim and purpose of this study is to evaluate the current body of knowledge to address the question as to the impact that the duration of exercise has on its relative effectiveness for inducing health and body compositional changes in individuals who are overfat to assist with developing periodized exercise protocols and establishing short and long term goals. A tiered meta-analysis of 92-studies and 200-exercise groupings were used for establishing pooled ES within and between groupings based on the increments of 4-week of duration and study designs of ≤8, 9-16, 17-23, 24-36, and ≥36 weeks. Analysis based on random-effect of response indicates a continuum of effectiveness within and between ET, RT and E+R based on duration. Where beneficial effectiveness is not indicated for any measures until after 8-weeks of continuous training with progressive effectiveness being noted in changes to cardiorespiratory fitness, inflammatory cytokines, and alteration of metabolic status from 12-weeks through 32-weeks of continuous training. Results indicate a greater ES for RT and E+R versus ET early in intervention that equalizes with longer durations. Supporting the use of RT and E+R within a periodized program. And secondarily, goals should be established first on performance gains and second body composition or health status modifications for the individual who is overfat.

Appetite and Energy Intake Responses to Acute Energy Deficits in Females versus Males

Purpose

To explore whether compensatory responses to acute energy deficits induced by exercise or diet differ by sex.

Methods

In experiment one, 12 healthy women completed three 9-h trials (control, exercise-induced (Ex-Def) and food restriction–induced energy deficit (Food-Def)) with identical energy deficits being imposed in the Ex-Def (90-min run, ∼70% of V˙O_2max) and Food-Def trials. In experiment two, 10 men and 10 women completed two 7-h trials (control and exercise). Sixty minutes of running (∼70% of V˙O_2max) was performed at the beginning of the exercise trial. The participants rested throughout the remainder of the exercise trial and during the control trial. Appetite ratings, plasma concentrations of gut hormones, and ad libitum energy intake were assessed during main trials.

Results

In experiment one, an energy deficit of approximately 3500 kJ induced via food restriction increased appetite and food intake. These changes corresponded with heightened concentrations of plasma acylated ghrelin and lower peptide YY_3–36. None of these compensatory responses were apparent when an equivalent energy deficit was induced by exercise. In experiment two, appetite ratings and plasma acylated ghrelin concentrations were lower in exercise than in control, but energy intake did not differ between trials. The appetite, acylated ghrelin, and energy intake response to exercise did not differ between men and women.

Conclusions

Women exhibit compensatory appetite, gut hormone, and food intake responses to acute energy restriction but not in response to an acute bout of exercise. Additionally, men and women seem to exhibit similar acylated ghrelin and PYY_3–36 responses to exercise-induced energy deficits. These findings advance understanding regarding the interaction between exercise and energy homeostasis in women.

Exercise, Appetite and Weight Control: Are There Differences between Men and Women?

Recent years have witnessed significant research interest surrounding the interaction among exercise, appetite and energy balance, which has important implications for health. The majority of exercise and appetite regulation studies have been conducted in males. Consequently, opportunities to examine sex-based differences have been limited, but represent an interesting avenue of inquiry considering postulations that men experience greater weight loss after exercise interventions than women. This article reviews the scientific literature relating to the acute and chronic effects of exercise on appetite control in men and women. The consensus of evidence demonstrates that appetite, appetite-regulatory hormone and energy intake responses to acute exercise do not differ between the sexes, and there is little evidence indicating compensatory changes occur after acute exercise in either sex. Limited evidence suggests women respond to the initiation of exercise training with more robust compensatory alterations in appetite-regulatory hormones than men, but whether this translates to long-term differences is unknown. Current exercise training investigations do not support sex-based differences in appetite or objectively assessed energy intake, and increasing exercise energy expenditure elicits at most a partial energy intake compensation in both sexes. Future well-controlled acute and chronic exercise studies directly comparing men and women are required to expand this evidence base.

Twenty-hour growth hormone secretory profiles after aerobic and resistance exercise

INTRODUCTION

The pulsatile secretion pattern of growth hormone (GH) is an important parameter of GH action at peripheral tissues, and more information is needed on how exercise impacts GH secretion. This study hypothesized that both aerobic and resistance exercise would exhibit dose-response relationships with respect to exercise duration and 20-h postexercise GH secretion.

METHODS

Eight healthy men randomly completed five separate conditions: 1) control (no exercise; CON), 2) a moderate-duration (1-h) aerobic exercise session (MA), 3) a long-duration (2-h) aerobic exercise session (LA), 4) a moderate-duration (1-h) resistance exercise session (MR), and 5) a long-duration (2-h) resistance exercise session (LR). Exercise intensity, diet, sleep, and physical activity were strictly controlled during each condition, and blood was sampled postexercise every 20 min for 20 h, and GH secretion parameters were analyzed via cluster and deconvolution analyses.

RESULTS

Only the 2-h aerobic exercise bout resulted in a significant amplification of GH secretion as evidenced by increases in GH burst peak amplitude (∼100%), basal GH secretion rate (∼127%), total GH basal secretion (∼120%), total pulsatile secretion (∼88%), and total GH secretion (∼89%) over the control (i.e., no exercise) condition. GH secretions for the resistance exercise conditions were not different from control.

CONCLUSIONS

The fact that the 2-h aerobic exercise condition resulted in higher energy expenditure than the other exercise conditions could offer a partial explanation for the greater GH amplification because of the metabolic effects that GH exerts in stimulating postexercise lipolysis. We conclude that extending the duration of aerobic exercise, but not resistance exercise, from 1- to 2-h significantly amplifies GH secretion during a 20-h period.

Diet, exercise or diet with exercise: comparing the effectiveness of treatment options for weight-loss and changes in fitness for adults (18-65 years old) who are overfat, or obese; systematic review and meta-analysis

There are number of means of methods to alter body composition, and metabolic issues, available for the adult who is overfat. The following is a systematic review and meta-analysis focused on comparing changes from treatment program for adults who are overfat based on analysis of aggregated effect size (ES) of inducing changes. So as to determine the relative effectiveness of such protocols and intervention plans of choice. This tiered meta-analysis of 66-population based studies, and 162-studywise groups, a clear pattern of ES being established across and within treatments. First, hypocaloric balance is necessary for changing body composition, but the effectiveness for establishing imbalance does not equate with the effectiveness for body compositional changes, or any biomarkers associated with metabolic issues. With analysis showing that there is a necessity to include exercise in combination with diet effectively elicit changes in body composition and biomarkers of metabolic issues. More importantly, the combination, resistance training (RT) was more effective than endurance training (ET) or combination of RT and ET, particularly when progressive training volume of 2-to-3 sets for 6-to-10 reps at an intensity of ≥75% 1RM, utilizing whole body and free-weight exercises, at altering body compositional measures (ES of 0.47, 0.30, and 0.40 for loss of BM, FM, and retention of FFM respectively) and reducing total cholesterol (ES = 0.85), triglycerides (ES = 0.86) and low-density lipoproteins (ES = 0.60). Additionally RT was more effective at reducing fasting insulin levels (ES = 3.5) than ET or ET and RT. Even though generally lower ES than RT, the inclusion of ET was more effective when performed at high intensity (e.g. ≥70% VO2max or HRmax for 30-minutes 3-4x's/wk), or in an interval training style than when utilizing the relatively common prescribed method of low-to-moderate (e.g., 50-70% VO2max or HRmax for at least equal time) steady state method, ES of 0.35, 0.39, and 0.13 for BM, FM, and FFM respectively. Thus indicating that focus of treatment should be on producing a large metabolic stress (as induced by RT or high levels of ET) rather than an energetic imbalance for adults who are overfat.

Physical activity and risk of fatty liver in people with different levels of alcohol consumption: a prospective cohort study

OBJECTIVE

To investigate whether physical activity affects the future incidence of fatty liver in people with never-moderate and heavy alcohol consumption.

DESIGN

Prospective cohort study.

SETTING

Health check-up programme at Meiji Yasuda Shinjuku Medical Center in Shinjuku Ward, Tokyo, Japan.

POPULATION

A total of 10,146 people aged 18 years or older without fatty liver enrolled through baseline surveys conducted from 2005 to 2007. They were grouped into never-moderate alcohol drinkers (n=7803) and heavy alcohol drinkers (n=2343) and followed until 2013.

MAIN OUTCOME MEASURE

Incident fatty liver diagnosed by ultrasound.

RESULTS

During a mean follow-up of 4.4 years (34,648 person-years), 1255 never-moderate alcohol drinkers developed fatty liver; 520 heavy alcohol drinkers developed fatty liver during a mean follow-up of 4.1 years (9596 person-years). For never-moderate alcohol drinkers, engaging in >3×/week of low-intensity (HR=0.82, 95% CI 0.71 to 0.96) and moderate-intensity (HR=0.56, 95% CI 0.39 to 0.81) physical activity significantly reduced incident fatty liver compared with those who engaged in physical activity <1×/week. For vigorous-intensity physical activity, frequencies of 2×/week (HR=0.57, 95% CI 0.38 to 0.86) and >3×/week (HR=0.55, 95% CI 0.38 to 0.79) were significantly associated with lower risk of incident fatty liver. In propensity-adjusted models, these significant associations still remained. By contrast, in heavy alcohol drinkers, there were no significant associations between the type or frequency of physical activity and incident fatty liver.

CONCLUSIONS

Physical activity had an independent protective effect on incident fatty liver only in the never-moderate alcohol drinkers, and the preventive effect increased with higher frequencies and intensities of physical activity.

Executive function and endocrinological responses to acute resistance exercise

This study had the following two aims: First, to explore the effects of acute resistance exercise (RE, i.e., using exercise machines to contract and stretch muscles) on behavioral and electrophysiological performance when performing a cognitive task involving executive functioning in young male adults; Second, to investigate the potential biochemical mechanisms of such facilitative effects using two neurotrophic factors [i.e., growth hormone (GH) and insulin-like growth factor-1 (IGF-1)] and the cortisol levels elicited by such an exercise intervention mode with two different exercise intensities. Sixty young male adults were recruited and randomly assigned to a high-intensity (HI) exercise group, moderate-intensity (MI) exercise group, and non-exercise-intervention (NEI) group. Blood samples were taken, and the behavioral and electrophysiological indices were simultaneously measured when individuals performed a Go/No-Go task combined with the Erikson Flanker paradigm at baseline and after either an acute bout of 30 min of moderate- or high-intensity RE or a control period. The results showed that the acute RE could not only benefit the subjects' behavioral (i.e., RTs and accuracy) performance, as found in previous studies, but also increase the P3 amplitude. Although the serum GH and IGF-1 levels were significantly increased via moderate or high intensity RE in both the MI and HI groups, the increased serum levels of neurotrophic factors were significantly decreased about 20 min after exercise. In addition, such changes were not correlated with the changes in cognitive (i.e., behavioral and electrophysiological) performance. In contrast, the serum levels of cortisol in the HI and MI groups were significantly lower after acute RE, and the changes in cortisol levels were significantly associated with the changes in electrophysiological (i.e., P3 amplitude) performance. The findings suggest the beneficial effects of acute RE on executive functioning could be due to changes in arousal, possibly modulated by the serum cortisol levels.

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.

The effect of exercise on the cardiovascular risk factors constituting the metabolic syndrome: a meta-analysis of controlled trials

Background

Numerous meta-analyses have investigated the effect of exercise in different populations and for single cardiovascular risk factors, but none have specifically focused on the metabolic syndrome (MetS) patients and the concomitant effect of exercise on all associated cardiovascular risk factors.

Objective

The aim of this article was to perform a systematic review with a meta-analysis of randomized and clinical controlled trials (RCTs, CTs) investigating the effect of exercise on cardiovascular risk factors in patients with the MetS.

Methods

RCTs and CTs ≥4 weeks investigating the effect of exercise in healthy adults with the MetS and published in a peer-reviewed journal up to November 2011 were included. Primary outcome measures were changes in waist circumference (WC), systolic and diastolic blood pressure, high-density lipoprotein cholesterol (HDL-C), triglycerides and fasting plasma glucose. Peak oxygen uptake (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\dot{{V}}\text{O}}_{{ 2 {\text{peak}}}} $$\end{document}) was a secondary outcome. Random and fixed-effect models were used for analyses and data are reported as means and 95% confidence intervals (CIs).

Results

Seven trials were included, involving nine study groups and 206 participants (128 in exercise group and 78 in control group). Significant mean reductions in WC −3.4 (95% CI −4.9, −1.8) cm, blood pressure −7.1 (95% CI −9.03, −5.2)/−5.2 (95% CI −6.2, −4.1) mmHg and a significant mean increase in HDL-C +0.06 (95% CI +0.03, +0.09) mmol/L were observed after dynamic endurance training. Mean plasma glucose levels −0.31 (95% CI −0.64, 0.01; p = 0.06) mmol/L and triglycerides −0.05 (95% CI −0.20, 0.09; p = 0.47) mmol/L remained statistically unaltered. In addition, a significant mean improvement in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\dot{{V}}\text{O}}_{{ 2 {\text{peak}}}} $$\end{document} of +5.9 (95% CI +3.03, +8.7) mL/kg/min or 19.3% was found.

Conclusions

Our results suggest that dynamic endurance training has a favourable effect on most of the cardiovascular risk factors associated with the MetS. However, in the search for training programmes that optimally improve total cardiovascular risk, further research is warranted, including studies on the effects of resistance training and combined resistance and endurance training.

Effects of high-intensity exercise training on body composition, abdominal fat loss, and cardiorespiratory fitness in middle-aged Korean females

The primary purpose of this study was to investigate the effects of high-intensity exercise training under relatively equal energy expenditure on whole body fat and abdominal fat loss, and cardiorespiratory fitness. Twenty-two untrained middle-aged Korean females were randomized into one of the following groups: control, low-intensity training group (LI), and high-intensity training group (HI). Subjects completed 14 weeks of training at 50% maximal oxygen consumption (LI) or 70% maximal oxygen consumption (HI) with the volume of exercise equated relative to kilograms of body weight. Weekly exercise volumes were 13.5 METs⋅h/week for the first 4 weeks, 18 METs⋅h/week for next 5 weeks, and 22.5 METs⋅h/week for the final 5 weeks. Data were analyzed using 2-way repeated measures ANOVA with post hoc test, using Bonferroni's correction. HI showed significant reductions in fat mass (p < 0.05), total abdominal fat (p < 0.01), and subcutaneous abdominal fat (p < 0.01). LI reduced total abdominal fat (p < 0.05), but there were no other significant changes found in the control or LI groups. Maximal oxygen consumption was enhanced in both HI and LI with no significant group difference. High-density lipoprotein cholesterol increased significantly in HI (p < 0.05). IL-6, C-reactive protein, TNF-α, and other blood lipids were unaltered following training. Results indicate that high-intensity exercise training is more beneficial in whole body and abdominal fat loss; however, cardiorespiratory enhancement shows a dose-response relationship with weekly exercise volume. It is suggested that 14 weeks of aerobic exercise training at either high- or low-intensity is not sufficient enough to induce changes in levels of inflammatory proteins.

The "Senobi" breathing exercise ameliorates depression in obese women through up-regulation of sympathetic nerve activity and hormone secretion

Obese individuals have an increased risk of developing depression. This study aimed to determine whether the "Senobi" breathing exercise (SBE), a stretching-breathing exercise that we have established, could relieve depression, especially in obese women. Forty premenopausal women, aged 40 to 49 years, participated in the present study. Twenty were healthy, and the other 20 were obese (body mass index > 25 and body fat > 30%) and in a depressive state (OWD). Sympathetic nerve activity determined by analyzing heart rate variability, and the hormone levels in the urine were investigated before and 30 min after one minute of SBE. The relative proportion of sympathetic nerve activity among healthy women in the daytime was 79.2 ± 2.3%, whereas that in OWD group was 30.4 ± 1.9%. After one minute of SBE, significant up-regulation of sympathetic nerve activity and increased concentrations of catecholamines, estradiol, and growth hormone (all P values < 0.001) were observed in OWD group. After 30 days of SBE, the sympathetic nerve activity and hormone levels had recovered in OWD group, and the depressive state, as evaluated by the Hamilton Depression Scale, had ameliorated. The "Senobi" breathing exercise was found to be effective for amelioration of depression in obese women possibly through up-regulation of sympathetic nerve activity and hormone secretion.