The effects of high-intensity interval training/moderate-intensity continuous training on the inhibition of fat accumulation in rats fed a high-fat diet during training and detraining

BACKGROUND

Compared with moderate-intensity continuous training (MICT), high-intensity interval training (HIIT) has at least a comparable effect on inhibiting an increase in fat. However, few studies have been conducted to examine the effects of detraining on body fat in rats fed a high-fat diet. The present study aimed to compare the effects of 10 weeks of HIIT or MICT as well as 6 weeks of detraining on body fat in rats fed a high-fat diet.

METHODS

After being fed a high-fat diet for 8 weeks, 54 female rats were randomly assigned to six groups: (1) CON-10, sedentary control for 10 weeks; (2) MICT-10, 10 weeks of MICT; (3) HIIT-10, 10 weeks of HIIT; (4) CON-16, sedentary control for 16 weeks; (5) MICT-16, 10 weeks of MICT followed by 6 weeks of training cessation; and (6) HIIT-16, 10 weeks of HIIT followed by 6 weeks of training cessation. The training was performed 5 days/week. The subcutaneous adipose tissue (inguinal; SCAT), visceral adipose tissue (periuterine; VAT) and serum lipid profile were analysed after 10 or 16 weeks. Adipose tissue triglyceride lipase (ATGL) protein expression in VAT was assessed by western blotting.

RESULTS

HIIT-10 and MICT-10 prevented the increase in SCAT, VAT and serum lipid levels seen in the CON group. During the 6-week detraining period, HIIT continued to prevent the increase in adipose tissue mass observed in the CON group, whereas MICT at least maintained this inhibition. The inhibition of fat mass increase was mainly the result of preventing adipocyte hypertrophy. The HIIT-10 and HIIT-16 groups showed the highest ATGL protein expression.

CONCLUSIONS

HIIT has a comparable effect to MICT on inhibiting fat accumulation in female rats; however, the inhibition of SCAT and VAT increase by HIIT is superior to MICT after short-term training cessation.

Comparative efficacy of exercise training modes on systemic metabolic health in adults with overweight and obesity: a network meta-analysis of randomized controlled trials

Objective

This network meta-analysis (NMA) was conducted to compare and rank the effects of training interventions including aerobic exercise (AE), resistance training (RT), combined aerobic and resistance training (CT), and high-intensity interval training (HIIT) on vital metabolic indicators in adults with overweight and obesity.

Methods

PubMed, Cochrane, Embase, and Web of Science were searched from 1990 to February 2023. Articles were included if they described randomized controlled trials (RCTs) examining the effects of exercise training on anthropometry parameters, lipid profiles, glucose metabolism, blood pressure, and cardiorespiratory fitness in adults with overweight and obesity. Weighted mean difference with 95% CI was calculated.

Results

A total of 28 studies with 1,620 patients were included. Results revealed that AE exerts best effects on weight loss (-2.35 [-4.05, -0.64]) and body mass index (-0.9 [-1.38, -0.42]), while HIIT is the most effective in reducing waist circumference (-5.93 [10.71, -1.15]), percentage body fat (-3.93 [-5.73, -2.12]), serum triglycerides (-20.55 [-37.20, -3.91]), and fasting blood glucose (-14.31 [-22.47, -6.16]) and improving VO2 max (7.41 [4.37, 10.45]). However, no significant benefit was observed in terms of total cholesterol and blood pressure.

Conclusions

AE is the optimal exercise type for reducing body weight and BMI, while HIIT exerts the most beneficial effects on improving body composition, cardiorespiratory fitness, and metabolic abnormalities in adults with overweight and obesity.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023444322, identifier CRD42023444322.

The effects of exercise training on circulating adhesion molecules in adults: A systematic review and meta-analysis

INTRODUCTION

The current meta-analysis investigated the effects of exercise training on circulating adhesion molecules i.e. soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in adults.

METHOD

PubMed, Web of Science, Scopus and Embase were searched to identify original articles, published in English languages journal from inception up to 31 August 2023 that compared the effects of exercise training with non-exercising control on sICAM-1 and sVCAM-1 in adults. Standardized mean differences (SMDs) and 95% CIs were calculated using random-effect models.

RESULTS

Twenty-three studies including 31 intervention arms and involving 1437 subjects were included in the meta-analysis. Exercise training effectively reduced sICAM-1 [SMD: -0.33 (95% CI -0.56 to -0.11), p = 0.004; I2 = 56.38%, p = 0.001; 23 intervention arms]. Subgroup analyses showed that sICAM-1 decreased in adults with age <60 years (p = 0.01) and BMI ≥ 27 kg/m2 (p = 0.002) and those with metabolic disorders (p = 0.004) and cardiovascular diseases (p = 0.005). In addition, aerobic (p = 0.02) and resistance training (p = 0.007) are effective in reducing sICAM-1. However, exercise training did not indicate a superior effect on sVCAM-1 [SMD: -0.12 (95% CI -0.29 to 0.05), p = 0.17; I2 = 36.29%, p = 0.04; 23 intervention arms].

CONCLUSION

Our results show that exercise training reduces sICAM-1, but not for sVCAM-1, where both aerobic and resistance training is effective in reducing sICAM-1 in adults with metabolic disorders and cardiovascular diseases.

TRIAL REGISTRATION

The current meta-analysis was registered at www.crd.york.ac.uk/prospero with ID registration number: CRD42023410474.

Long-term effects of different exercise training modes on cytokines and adipokines in individuals with overweight/obesity and cardiometabolic diseases: A systematic review, meta-analysis, and meta-regression of randomized controlled trials

The present study aimed to investigate the evidence on the effects of different long-term training interventions (aerobic [AeT], resistance [RT], and combined [COMB]) and spontaneous physical activity (PA) in modifying cytokines and adipokines in individuals with overweight or obesity with or without cardiometabolic diseases while considering potential confounders. Although exercise interventions have become a potentially effective tool for preventing and treating metabolic diseases, the evidence provided by previous systematic reviews is inconclusive since several potential confounders have yet to be addressed. Therefore, we conducted a systematic literature search in Medline, Cochrane, and Embase databases from January 2000 to July 2022 and performed a meta-analysis. Inclusion criteria retrieved 106 full texts comprising 8,642 individuals with a range BMI of 25.1-43.8 kg m^-2 . We found that independently of the training mode, exercise had a beneficial effect on diminishing Adiponectin, C-reactive protein (CRP), IL-6, IL-18, IL-20, Leptin, sICAM, and TNF-α levels circulating levels. Furthermore, by subsequent analysis, we detected differential effects of AeT, RT, and COMB, with sex, age, body composition, and trial length acting as moderators. The comparison of training modes revealed a difference favoring COMB over AeT for regulating the increase in CRP with no differences in the remaining biomarkers. Meta-regression analysis revealed an effect of change in maximal oxygen uptake (VO_2max ) on CRP, IL-6, and TNF-α, while IL-10 was influenced by the change in body fat. The results suggest that all interventions, except PA, are effective in lessening this population's inflammatory status, provided that exercise results in an increase of VO_2max .

Effects of exercise training on inflammatory and cardiometabolic health markers in overweight and obese adults: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

The improvements in inflammation and cardiometabolic health play an important role in the prevention and treatment of obesity. However, the interactions between different exercise training (ET) modalities with inflammatory and cardiometabolic biomarkers are not completely understood. This systematic review and meta-analysis investigated the effects of ET on inflammatory and cardiometabolic health markers in overweight and obese adults.

EVIDENCE ACQUISITION

A systematic search was conducted in PubMed, CINAHL, MEDLINE, Cochrane, Google Scholar, Scopus and Web of Science up to December 15, 2021. Thirty-five studies including 2752 participants were included and analyzed using a random-effects model to estimate weighted mean differences (MD) with 95% confidence intervals (CI).

EVIDENCE SYNTHESIS

The meta-analysis found that ET significantly (P<0.05) increased adiponectin (WMD: 0.72 µg/mL; 95% CI: 0.60 to 0.84; SMD=0.65) and maximal oxygen consumption levels (WMD: 5.26 mL.kg.min; 95% CI: 3.84, 6.69; SMD=1.21). Moreover, ET significantly (P<0.05) reduced fasting insulin (WMD: -2.40 μIU/mL; 95% CI: -3.43 to -1.37; SMD=-0.87), fasting blood glucose (WMD: -5.41 mg/dL; 95% CI: -7.91, -2.91; SMD=-0.66), insulin resistance (WMD: -0.66; 95% CI: -1.08, -0.24; SMD=-0.66) and triglyceride levels (WMD: -10.88 mg/dL; 95% CI: -17.61, -4.15; SMD=-0.91). No significant changes were observed in interleukin-6, tumor necrosis factor-α, leptin, C-reactive protein and cholesterol concentrations. Subgroup analysis by type of training indicated that aerobic and resistance exercise had the most consistent beneficial effects as compared to other modalities.

CONCLUSIONS

Our findings suggest that ET may improve inflammation and cardiometabolic health in overweight and obese adults. Aerobic and resistance training appear to be more beneficial for improving adiponectin, fasting insulin, fasting blood glucose, insulin resistance index and triglyceride levels as compared to other exercise modalities. Further long-term studies are required to confirm and expand on these findings.

Exercise training and de-training effects on serum leptin and TNF-α in high fat induced diabetic rats

BACKGROUND

Adipocytokines, which are secreted by the adipose tissue, contribute to the pathogenesis of obesity-related complications. To evaluate this assumption, we investigated the effects of aerobic exercise training (AET), resistance exercise training (RET), and 4 weeks of de-training on serum leptin and TNF-α levels in diabetic rats.

METHOD

36 Wistar rats were divided into normal diet (ND) (control, RET, AET) and high-fat diet (HFD) + STZ (control, RET, AET) groups. Serum insulin, leptin, and TNF-α levels were assessed by commercial ELISA kits. Also fasting blood glucose (FBG), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) levels were measured by the colorimetric kits.

RESULTS

Diabetes induction increased body weight (BW) and FBG, and decreased insulin compared to the ND rats' groups (p < 0.001). 12-weeks of AET and RET programs in the trained diabetic rats led to a decrease in TG, LDL-C, leptin, TNF-α, and FBG, and an increase in insulin compared to the HFD + STZ-C group (p < 0.001). Besides, there was no difference between AET and RET in improving the variables studied (p > 0.05). Also, de-training led to increased BW, TG, leptin, and TNF-α compared to the end of the exercise training (p < 0.05). The correlation between the variables studied was established at different stages of the study (p < 0.05), and only BW was not correlated with insulin during exercise training and de-training (p > 0.05).

CONCLUSION

These findings indicate that both AET and RET are useful in reducing levels of serum adipocytokines (TNF-α, leptin) in diabetic and non-diabetic rats. At the same time, 4 weeks of de-training was sufficient to lose the metabolic adaptations.

Phase Angle as an Easy Diagnostic Tool of Meta-Inflammation for the Nutritionist

Phase angle (PhA), a noninvasive bioimpedance marker, is a useful tool for nutritional screening in several diseases. C-reactive protein (CRP), a strong risk factor for metabolic and cardiovascular diseases, is a commonly used biomarker of meta-inflammation. As both PhA and CRP are influenced by age, BMI, and nutritional status, and exhibit a clear sex dimorphism, we examined the association between PhA and CRP levels in 1855 subjects (680 males and 1175 females), aged 18-59 years, with BMIs ranging from 19.5 to 69.4 kg/m², stratified according to sex. PhA values and CRP levels were significantly lower in females than males (p < 0.001), while the adherence to the Mediterranean diet (MD) was lower in males compared to females (p < 0.001). After adjusting for age, physical activity, BMI, waist circumference, and adherence to the MD, PhA remained negatively associated with CRP levels in both genders (p < 0.001). In the ROC analysis, PhA ≤ 5.5° in males and ≤5.4° in females were the threshold values predicting increased hs-CRP levels. These results suggested that PhA might represent a valid predictor of CRP levels in both sexes regardless of body weight and adherence to the MD, which avoids the collection of blood sampling and expensive biochemical assays.

The effects of physical activity on adipokines in individuals with overweight/obesity across the lifespan: A narrative review

This narrative review summarizes current knowledge on the effects of physical activity (PA) on adipokine levels in individuals with overweight and obesity. Approximately 90 investigations including randomized control, cross-sectional and longitudinal studies that reported on the effects of a single session of PA (acute) or long-term PA (chronic) on adipokine levels in individuals with overweight/obesity were reviewed. The findings support the notion that there is consensus on the benefits of chronic exercise training-regardless of the mode (resistance vs. aerobic), intensity and cohort (healthy vs. diabetes)-on adipokine levels (such as tumour necrosis factor-alpha, interleukin-6, adiponectin, visfatin, omentin-1 and leptin). However, several confounding factors (frequency, intensity, time and type of exercise) can alter the magnitude of the effects of an acute exercise session. Available evidence suggests that PA, as a part of routine lifestyle behaviour, improves obesity complications by modulating adipokine levels. However, additional research is needed to help identify the most effective interventions to elicit the most beneficial changes in adipokine levels in individuals with overweight/obesity.

Resistance training leads to large improvements in strength and moderate improvements in physical function in adults who are overweight or obese: a systematic review

QUESTIONS

What are the effects of resistance training on muscle strength, physical function and muscle power in adults who are overweight or obese? Which factors moderate the effects?

DESIGN

Systematic review of randomised controlled trials, with random effects meta-analyses and meta-regressions.

PARTICIPANTS

Adults who are overweight or obese.

INTERVENTION

Resistance training lasting ≥ 4 weeks.

OUTCOME MEASURES

Muscle strength, muscle power and physical function.

RESULTS

Thirty trials with 1,416 participants met the eligibility criteria. Pooled analyses indicated that resistance training has a large beneficial effect on muscle strength (SMD 1.39, 95% CI 1.05 to 1.73, I² = 85%) and a moderate effect on physical function (SMD 0.67, 95% CI 0.25 to 1.08, I² = 71%) in adults who are overweight or obese. However, the effect of resistance training on muscle power was unclear (SMD 0.42, 95% CI -3.3 to 4.2, I² = 46%). The effect of resistance training on strength was greatest for the upper body (versus lower/whole body: β = 0.35, 95% CI 0.05 to 0.66) and in dynamic strength tests (versus isometric/isokinetic: β = 1.20, 95% CI 0.60 to 1.81), although trials judged to have good methodological quality reported statistically smaller effects (versus poor/fair quality: β = -1.21, 95% CI -2.35 to -0.07). Concomitant calorie restriction did not modify strength gains but reduced the effect of resistance training on physical function (β = -0.79, 95% CI -1.41 to -0.17). Small study effects were evident for strength outcomes (β = 5.9, p < 0.001).

CONCLUSIONS

Resistance training has a large positive effect on muscle strength and a moderate effect on physical function in adults who are overweight or obese. However, the effect of resistance training on muscle power is uncertain. In addition, concomitant calorie restriction may compromise the functional adaptations to resistance training.

REGISTRATION

PROSPERO CRD42019146394.

Moderate walnut consumption improved lipid profile, steroid hormones and inflammation in trained elderly men: a pilot study with a randomized controlled trial

The present study aimed to investigate the effect of walnut consumption on lipid profile, steroid hormones and inflammation in trained elderly men performing concurrent (resistance and endurance) training. Twenty healthy elderly males were divided into two matched groups, in a randomized controlled trial, that trained three sessions per week: concurrent training + dietary walnut consumption (15 g/day for six weeks, CTW: n = 10); concurrent training + control diet (CT: n = 10). Fasting blood samples were taken 48 hours before and after intervention for biochemical assessments. levels of high-density lipoprotein (HDL) increased only in CTW compared to baseline (19.8%, p < 0.01). Total cholesterol (TC), low-density lipoprotein (LDL) and triglyceride (TG) levels significantly decreased only for CTW (i.e., 13%, 18%, and 18.5% at p < 0.01 for all). Testosterone (T) increased after the training compared to pre-training for CTW and CT (10.3%, p < 0.01, 4.27% p < 0.05, respectively), but the increase was significantly higher in CTW (p < 0.05). Serum cortisol (C) was lower for CTW compared to CT (p < 0.01). C-reactive protein (CRP) decreased in CTW in comparison with CT. The present study revealed that 6-week moderate walnut supplementation (15 g/day) improved lipid profile, steroid hormones and systematic inflammation in aged men performing concurrent training. These findings could be attributable to the potential effect of polyunsaturated fatty acids (PUFA) contained in walnut (linoleic acid, n-6; linolenic acid, n-3).

Effects of a four week detraining period on physical, metabolic, and inflammatory profiles of elderly women who regularly participate in a program of strength training

Background

Human aging has innumerable health implications, including loss of muscle mass and increased circulating inflammatory markers. Resistance exercise in the elderly can prevent muscle mass loss and improve the inflammatory profile. Conversely, detraining can reverse this picture. Thus, there is a strong need for studies with the elderly population to clarify the real impacts of a training interruption. Therefore, the objective of this study was to analyze the inflammatory profile of resistance trained elderly women after 4 weeks of detraining.

Methods

Seventeen elderly women with regular participation in an exercise program participated in the study. Body mass index (BMI), physical activity level assessments, total cholesterol and its fractions, triglycerides, glycemia and insulin blood levels, IL-1β, IL-4, IL-6, IL-10, IL-13, TNF-α, IFNγ, and MCP-1 were assessed before and after the detraining protocol.

Results

The 4 week detraining period decreased physical fitness without altering body mass and BMI. The short detraining period was able to induce some metabolic disturbances in elderly women who regularly participate in a program of strength training, such as increasing HOMA-IR (0.72 ± 0.14 to 0.81 ± 0.23; p = 0.029), and increasing total blood cholesterol (178.21 ± 23.64 to 220.90 ± 64.98 mg/dL; p = 0.008) and LDL fraction (111.79 ± 21.09 to 155.33 ± 60.95 mg/dL; p = 0.048). No alteration in levels of inflammatory cytokines was observed, however, this detraining period significantly reduced IL-13 (44.84 ± 100.85 to 35.84 ± 78.89 pg/mL; p = 0.031) a Th2 cytokine that induces M2 macrophage polarization.

Conclusions

These data demonstrate that even a short period of detraining is harmful for elderly women who regularly participate in a program of strength training, since it impairs physical performance, insulin sensitivity and cholesterol metabolism.

Effects of exercise cessation on adipose tissue physiological markers related to fat regain: A systematic review

Tissues usually super compensate during the period that follow physical exercise. Although this is widely accepted for muscle and glycogen, the compensatory effect is not usually applied to fat tissues. Notwithstanding, evidence for this has been present since the 1970s when it was first suggested that the increased lipogenic activity in response to training might be an adaptation that enables to restore an energy reserve that can be used in times of need. In this context, the present review aimed to summarize information about the effect of detraining on fat metabolism and the physiological responses associated with fat regain. A systematic search on PubMed and Scielo was performed using "training cessation," "detraining," "exercise detraining," and "exercise cessation" combined with "fat tissue," "adipose tissue," "adipose metabolism," and "fat metabolism," as descriptors. From 377 results, 25 were included in this review, 12 humans and 13 rodents, resulting in a sample of 6772 humans and 613 animals. The analysis provided evidence for fat super compensation, as well as differences in humans and rodents, among different protocols and possible mechanisms for fat gain after exercise cessation. In summary, exercise cessation appears to increase the ability of the adipose tissue to store energy. However, caution should be taken, especially regarding conclusions based on investigations on humans, considering the multiple factors that could affect fat metabolism.

Exercise cessation in active older adults: Effects on inflammatory markers and adiponectin

AIM

To evaluate the effects of 3 months of exercise cessation in physically active older individuals on inflammatory biomarkers and adiponectin, and examine any association modifications in physical functioning.

METHODS

We evaluated the effects of exercise cessation in 49 physically active older adults on inflammatory biomarkers, adiponectin and physical functioning. Participants (38 women, 11 men) were aged >65 years old and had attended a 9-month supervised exercise program. After 3 months of exercise cessation, we measured anthropometry, physical activity, strength, balance, endurance exercise, cholesterol, triglycerides, C-reactive protein, glucose, glycosylated hemoglobin A1c, interleukin-6 and adiponectin levels.

RESULTS

Adiponectin was positively correlated with high-density lipoprotein and negatively correlated with triglyceride levels after exercise cessation. Higher adiponectin levels were correlated with worse dynamic balance, endurance exercise and lower limb strength (men only), which might be explained by the adiponectin resistance hypothesis.

CONCLUSIONS

Adiponectin therefore might be a promising biomarker of physical dysfunction in older adults, although further research is necessary to understand the mechanisms involved in its double-sided effects. Geriatr Gerontol Int 2020; 20: 494-499.

Long-term Effects of Moderate versus High Durations of Aerobic Exercise on Biomarkers of Breast Cancer Risk: Follow-up to a Randomized Controlled Trial

BACKGROUND

The optimal lifestyle for breast cancer prevention over the long term is unclear. We aimed to determine whether or not the amount of exercise prescribed in a year-long exercise intervention influences breast cancer biomarker levels 1 year later.

METHODS

We conducted a 24-month follow-up study (2012-2014) to the Breast Cancer and Exercise Trial in Alberta (BETA), a 12-month, two-armed (1:1), two-center randomized controlled trial of exercise in 400 cancer-free, postmenopausal women. The exercise prescription was moderate-vigorous aerobic exercise, 5 days/week (3 days/week supervised) for 30 minutes/session (MODERATE) or 60 minutes/session (HIGH). Participants were asked not to change their usual diet. We used linear mixed models to compare biomarker concentrations (C-reactive protein, insulin, glucose, HOMA-IR, estrone, sex hormone binding globulin, total estradiol, and free estradiol) over time (0, 12, and 24 months) by group (MODERATE, HIGH), using group-time interactions.

RESULTS

After 12 months of no intervention, 24-month fasting blood samples were available for 84.0% and 82.5% of MODERATE and HIGH groups, respectively (n = 333/400). We found no evidence that 0 to 24- or 12 to 24-month biomarker changes differed significantly between randomized groups (HIGH:MODERATE ratio of mean biomarker change ranged from 0.97 to 1.06, P values >0.05 for all). We found more favorable biomarker profiles among participants who experienced greater than the median fat loss during the trial.

CONCLUSIONS

Prescribing aerobic exercise for 300 versus 150 minutes/week for 12 months to inactive, postmenopausal women had no effects on longer-term biomarkers.

IMPACT

Exercise may lead to larger improvements in breast cancer biomarkers after intervention among women who also experience fat loss with exercise.

Effect of Strength Training on Lipid and Inflammatory Outcomes: Systematic Review With Meta-Analysis and Meta-Regression

Background: The aim of this study was to perform a systematic review with meta-analysis and meta-regressions evaluating the effects of isolated strength training (ST), compared with a control group, on total cholesterol (TC), triglycerides (TG), low-density (LDL), high-density lipoprotein (HDL), C-reactive protein (CRP), and adiponectin of adults. Methods: Embase, PubMed, Cochrane, and Scopus data sources were searched up to May 2017. Clinical trials that compared ST with a control group of adults older than 18 years, which evaluated blood TC, TG, LDL, HDL, CRP, or adiponectin as an outcome were included. Random effect was used and the effect size (ES) was calculated by using the standardized mean difference with a 95% confidence interval. Results: ST promotes a reduction in TC (ES: -0.399; P < .001), TG (ES: -0.204; P = .002), LDL (ES: -0.451; P < .001), and CRP (ES: -0.542; P = .01) levels. In addition, ST is associated to an increase in HDL (ES: 0.363; P < .001) and adiponectin concentrations (ES: 1.105; P = .01). Conclusion: ST promotes decreases in TC, TG, LDL, and CRP levels and increases HDL and adiponectin concentrations. Thus, progressive ST could be a potential therapeutic option for improving abnormalities in lipid and inflammatory outcomes in adults.

Comparison of Serum Cytokine Levels in Men Who are Obese or Men Who are Lean: Effects of Nonlinear Periodized Resistance Training and Obesity

Nikseresht, M. Comparison of serum cytokine levels in men who are obese or men who are lean: effects of nonlinear periodized resistance training and obesity. J Strength Cond Res 32(6): 1787-1795, 2018-This study examined the capacity of nonlinear resistance training (NRT) to alter some cytokines and markers of insulin resistance in men who are obese. An additional aim was to compare these variables between men who are obese and men who are lean. Age- and fitness-matched men who are obese were randomly allocated to NRT (n = 12) and control (CON, n = 10) groups. An age- and fitness-matched control group of lean men (n = 11) were also recruited for baseline comparison. The NRT (12 weeks, 3 d·wk, 5-11 exercises) performed at different intensities (40-95% of 1 repetition maximum) with flexible periodization. Serum insulin, glucose, interleukin (IL)-6, IL-10, IL-17A, and IL-20 levels were measured at baseline and after training. Men who were obese had significantly lower IL-20 and higher glucose, insulin, insulin resistance (homeostasis model assessment, HOMA-IR), IL-10, and IL-6 than lean participants at baseline (all, p ≤ 0.05). There were significant negative correlations between IL-10 with anthropometric markers and HOMA-IR at baseline, whereas these variables were inversely correlated with IL-20. After training, V[Combining Dot Above]O2peak and 1 repetition maximum for bench press and knee extension of the NRT increased significantly compared with CON, which was accompanied by significant reductions in anthropometric markers, insulin and HOMA-IR. IL-6 and IL-17A did not change significantly in response to training, but IL-10 and IL-20 increased significantly compared with baseline. An inverse relationship between the percent IL-20 increase and the percent waist circumference decrease suggests that adipocytes, or other metabolic factors such as glucose, may exert a lowering-effect on IL-20.

Aerobic Exercise Training and Inducible Inflammation: Results of a Randomized Controlled Trial in Healthy, Young Adults

Background Consensus panels regularly recommend aerobic exercise for its health-promoting properties, due in part to presumed anti-inflammatory effects, but many studies show no such effect, possibly related to study differences in participants, interventions, inflammatory markers, and statistical approaches. This variability makes an unequivocal determination of the anti-inflammatory effects of aerobic training elusive. Methods and Results We conducted a randomized controlled trial of 12 weeks of aerobic exercise training or a wait list control condition followed by 4 weeks of sedentary deconditioning on lipopolysaccharide (0, 0.1, and 1.0 ng/mL)-inducible tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and on toll-like receptor 4 in 119 healthy, sedentary young adults. Aerobic capacity by cardiopulmonary exercise testing was measured at study entry (T1) and after training (T2) and deconditioning (T3). Despite a 15% increase in maximal oxygen consumption, there were no changes in inflammatory markers. Additional analyses revealed a differential longitudinal aerobic exercise training effect by lipopolysaccharide level in inducible TNF -α ( P=0.08) and IL-6 ( P=0.011), showing T1 to T2 increases rather than decreases in inducible (lipopolysaccharide 0.1, 1.0 versus 0.0 ng/mL) TNF- α (51% increase, P=0.041) and IL-6 (42% increase, P=0.11), and significant T2 to T3 decreases in inducible TNF- α (54% decrease, P=0.007) and IL-6 (55% decrease, P<0.001). There were no significant changes in either group at the 0.0 ng/mL lipopolysaccharide level for TNF- α or IL-6. Conclusions The failure to support the primary hypotheses and the unexpected post hoc findings of an exercise-training-induced proinflammatory response raise questions about whether and under what conditions exercise training has anti-inflammatory effects. Clinical Trial Registration URL : http://www.clinicaltrials.gov . Unique identifier: NCT 01335737.

Sarcopenic obesity in older adults: aetiology, epidemiology and treatment strategies

The prevalence of obesity in combination with sarcopenia (the age-related loss of muscle mass and strength or physical function) is increasing in adults aged 65 years and older. A major subset of adults over the age of 65 is now classified as having sarcopenic obesity, a high-risk geriatric syndrome predominantly observed in an ageing population that is at risk of synergistic complications from both sarcopenia and obesity. This Review discusses pathways and mechanisms leading to muscle impairment in older adults with obesity. We explore sex-specific hormonal changes, inflammatory pathways and myocellular mechanisms leading to the development of sarcopenic obesity. We discuss the evolution, controversies and challenges in defining sarcopenic obesity and present current body composition modalities used to assess this condition. Epidemiological surveys form the basis of defining its prevalence and consequences beyond comorbidity and mortality. Current treatment strategies, and the evidence supporting them, are outlined, with a focus on calorie restriction, protein supplementation and aerobic and resistance exercises. We also describe weight loss-induced complications in patients with sarcopenic obesity that are relevant to clinical management. Finally, we review novel and potential future therapies including testosterone, selective androgen receptor modulators, myostatin inhibitors, ghrelin analogues, vitamin K and mesenchymal stem cell therapy.

Resistance training reduces metabolic syndrome and inflammatory markers in older women: A randomized controlled trial

BACKGROUND

This study analyzed the effects of a 12-week resistance training (RT) program without dietary interventions on metabolic syndrome (MetS) components and inflammatory biomarkers in older women.

METHODS

Fifty-three older women (mean [±SD] age 70.4 ± 5.7 years; mean body mass index 26.7 ± 4.0 kg/m² ) were randomly assigned to a training group (TG; n = 26) that performed 12 weeks of an RT program or a control group (CG; n = 27) that did not perform any type of physical exercise over the same period. Body composition (dual energy X-ray absorptiometry), muscular strength (one-repetition maximum tests), blood pressure (BP), and blood sample measurements were performed before and after intervention.

RESULTS

After the 12-week period, there were significantly reductions (P < 0.05) in glucose levels (-20.4% vs -0.3%), waist circumference (-1.5% vs +2.0%), and systolic BP (-6.2% vs +0.9%), and complete normalization of MetS prevalence (18% at baseline vs. 0% after 12-weeks RT) in the TG. Moreover, C-reactive protein and tumor necrosis factor-α concentrations decreased in the TG (-28.6% and -21.6%, respectively), but increased in the CG (+34.5% and +13.3%, respectively). In addition there were positive improvements in the MetS Z-score in the TG but not CG (-21.6% vs +13.3%, respectively).

CONCLUSION

The results suggest that a 12-week RT program seems to effectively reduce MetS components and inflammatory biomarkers in older women, regardless of dietary intervention. The RT-induced adaptations in body composition and inflammatory biomarkers appear to be related to healthy adaptations in risk factors for MetS.

Aerobic vs. resistance exercise in non-alcoholic fatty liver disease: A systematic review

BACKGROUND & AIMS

Exercise is a first-line therapy for patients with non-alcoholic fatty liver disease (NAFLD). We sought to: 1) summarize effective aerobic and resistance exercise protocols for NAFLD; and 2) compare the effects and energy consumption of aerobic and resistance exercises.

METHODS

A literature search was performed using PubMed, Web of Science, and Scopas to January 28, 2016. From a total of 95 articles, 23 studies including 24 aerobic and 7 resistance exercise protocols were selected for the summary of exercise protocols. Twelve articles including 13 aerobic and 4 resistance exercise protocols were selected for the comparative analysis.

RESULTS

For aerobic exercise, the median effective protocol was 4.8 metabolic equivalents (METs) for 40min/session, 3times/week for 12weeks. For resistance exercise, the median effective protocol was 3.5 METs for 45min/session, 3times/week for 12weeks. Aerobic and resistance exercise improved hepatic steatosis. No significant difference was seen in the duration, frequency, or period of exercise between the two exercise groups; however, %VO₂max and energy consumption were significantly lower in the resistance than in the aerobic group (50% [45-98] vs. 28% [28-28], p=0.0034; 11,064 [6394-21,087] vs. 6470 [4104-12,310] kcal/total period, p=0.0475).

CONCLUSIONS

Resistance exercise improves NAFLD with less energy consumption. Thus, resistance exercise may be more feasible than aerobic exercise for NAFLD patients with poor cardiorespiratory fitness or for those who cannot tolerate or participate in aerobic exercise. These data may indicate a possible link between resistance exercise and lipid metabolism in the liver.

LAY SUMMARY

Both aerobic and resistance exercise reduce hepatic steatosis in non-alcoholic fatty liver disease (NAFLD) with similar frequency, duration, and period of exercise (40-45min/session 3times/week for 12weeks); however, the two forms of exercise have different characteristics. Intensity and energy consumption were significantly lower for resistance than for aerobic exercise. Resistance exercise may be more feasible than aerobic exercise for NAFLD patients with poor cardiorespiratory fitness or for those who cannot tolerate or participate in aerobic exercise.

Detraining-induced alterations in adipokines and cardiometabolic risk factors after nonlinear periodized resistance and aerobic interval training in obese men

This study compared the effects of nonlinear resistance training (NRT), aerobic interval training (AIT), and detraining on adipokines and cardiometabolic risk factors in middle-aged obese men. Thirty-three obese men were randomly allocated to NRT (n = 12), AIT (n = 10), and control (CON, n = 11) groups. Subjects in experimental groups performed exercise protocols 3 days per week for 12 weeks followed by a 4-week detraining period. The NRT involved 55 min of weight training with flexible periodization. The AIT consisted of running on a treadmill (4 × 4-min intervals at 90% of maximal heart rate, with each interval separated by 3 min at 65%). Peak oxygen consumption increased significantly after training compared with CON (P < 0.01), but it increased more in the AIT group than in the NRT group (P = 0.004). After detraining, peak oxygen consumption decreased significantly in both training groups (P < 0.001); however, the value in the AIT group was still higher than that in the CON group (P = 0.003). No significant changes were observed in serum levels of omentin-1 and interleukin (IL)-18 after training (P > 0.05), but omentin-1 decreased significantly in both training groups and IL-18 increased significantly in the NRT group after detraining (P < 0.05). High-density lipoprotein cholesterol (HDL-C) increased significantly after training in the AIT group compared with the CON group (P < 0.05) and returned to the pre-training level after detraining. Conversely, apelin-13 increased significantly in response to training, compared with baseline (P < 0.05), and remained unchanged after detraining. Both training regimens had similar effects on most markers; however, AIT seems to have stronger anti-coronary disease effects (as indicated by HDL-C and peak oxygen consumption) than NRT.

Effect of resistance training on C-reactive protein, blood glucose and lipid profile in older women with differing levels of RT experience

The purpose of this study was to analyze the effects of a progressive resistance training (RT) program on C-reactive protein (CRP), blood glucose (GLU), and lipid profile in older women with differing levels of RT experience. Sixty-five older women (68.9 ± 6.1 years, 67.1 ± 13.1 kg) were separated according to RT experience: an advanced group composed by 35 participants who previously carried out 24 weeks of RT and a novice group composed by 30 participants without previous experience in RT (n = 30). Both groups performed a RT program comprised of eight exercises targeting all the major muscles. Training was carried out 3 days/week for 8 weeks. Serum triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), GLU, and CRP concentrations were determined pre- and post- intervention after 12 h fasting. A significant group by time interaction (P < 0.05) for the TC (novice = -1.9% vs. advanced = 1.0%), and CRP (novice = -22.9% vs. advanced = -54.5%) was observed. A main effect of time (P < 0.05) was identified for the GLU (novice = -2.6% vs. advanced = -6.6%), TG (novice = -12.9% vs. advanced = -5.7%), HDL-C (novice = +6.7% vs. advanced = +2.6%), and LDL-C (novice = -34.0% vs. advanced = -25.4%). These results suggest that RT improves the metabolic profile of older women and that training for a longer period of time seems to produce more pronounced reductions mainly on CRP.

The effects of short-term high-intensity interval training vs. moderate-intensity continuous training on plasma levels of nesfatin-1 and inflammatory markers

OBJECTIVES

Exercise training is an effective method of weight management, and knowing about its influence on the hormones involved in the regulation of food intake and inflammation could be useful for body weight management. Therefore, the purpose of this study was to compare the effects of 6 weeks of high-intensity interval training (HIIT) and moderate-intensity continuous exercise training (MCT) on nesfatin-1, interleukin (IL)-6, and tumor necrosis factor alpha (TNF-α).

DESIGN AND METHODS

Thirty sedentary overweight men (Mean±SD; age, 25±1 years) were divided into three (n=10) body mass index-matched groups. The participants in the training groups performed either HIIT or MCT protocols 3 days per week for 6 weeks followed by a week of detraining.

RESULTS

Plasma IL-6 and TNF-α did not significantly change after training, but nesfatin increased significantly only with HIIT compared with the control group (p<0.05). In addition, fasting glucose, insulin, and homeostasis model estimated insulin resistance (HOMA-IR), decreased significantly following both HIIT and MCT training (p<0.05). After a detraining period, the plasma nesfatin-1 did not return to pre-training levels in the HIIT group.

CONCLUSIONS

Both the HIIT and MCT groups had similar effects on inflammatory markers and insulin resistance in men who are overweight, but the HIIT seems to have better anorectic effects (as indicated by nesfatin) compared with MCT.