Fitness versus adiposity in cardiovascular disease risk

Exercise Combined with a Low-Calorie Diet Improves Body Composition, Attenuates Muscle Mass Loss, and Regulates Appetite in Adult Women with High Body Fat Percentage but Normal BMI

BACKGROUND

The present study aimed to examine the effects of a 500 kcal reduction in daily energy intake alone and in combination with 90 min of moderate-to-vigorous aerobic exercise per week on body weight, body composition, and appetite sensations in young women with normal BMI and abnormal body fat percentage.

METHODS

sixty-six young women with normal BMI and abnormal body fat percentage (21.33 ± 1.20 kg/m2 and 34.32 ± 2.94%) were randomly assigned into three groups: (1) caloric restriction (CR; n = 22), (2) caloric restriction with exercise (CR-EX; n = 22), and (3) control (C; n = 22). Data on anthropometry, blood samples, and subjective appetite sensations pre- and post-intervention were collected.

RESULTS

After 4 weeks of intervention, CR and CR-EX groups both reduced body weight, fat percentage, and waist and hip circumferences compared to the C group (p < 0.05). Muscle mass of the CR group was significantly lower than that of the C group (-1.21 ± 0.86 kg vs. -0.27 ± 0.82 kg, p < 0.05), and no significant difference between CR-EX and C groups was observed. For appetite sensations, the subjects of the CR group showed significant increases in change of scores in desire to eat and prospective consumption than that of the C group (p < 0.05), while no significant difference between CR-EX and C groups was observed.

CONCLUSION

A 500 kcal reduction in daily energy intake alone and in combination with 90 min of moderate-to-vigorous aerobic exercise per week could both reduce weight and improve body composition in young adult women with normal BMI and abnormal body fat percentage. More importantly, calorie restriction combined with exercise intervention was superior to calorie restriction alone in improving muscle mass loss and regulating appetite sensations.

Implications of pre-transplant sarcopenia and frailty in patients with non-alcoholic steatohepatitis and alcoholic liver disease

Frailty manifesting as sarcopenia is an independent risk factor for mortality in cirrhosis, and often presents in low model for end-stage liver disease (MELD) patients. Its etiology is multifactorial, but key physiologic changes culminate in altered energy utilization in the fasting state, preferentially utilizing muscle amino acids for gluconeogenesis thereby promoting sarcopenia. Hyperammonemia alters the circulating amino acid profile, diminishing pro-muscle branched-chain amino acids like leucine. The metabolic syndrome worsens sarcopenia through multi-tissue insulin resistance. Alcohol also exacerbates sarcopenia as a direct muscle toxin and inhibitor of growth signaling. Therapy is aimed at alcohol cessation, frequent high-protein meals, branched-chain amino acid supplementation, and diminished time spent fasting. Moderate exercise can improve muscle mass and muscle quality, though precise exercise regimens have not yet been explicitly determined. Studies are ongoing into the effects of myostatin antagonists and insulin sensitizers. The Liver Frailty Index can predict patients most at risk of poor outcome and should be considered in the management of all cirrhotic patients. Specialty testing like dual-energy X-ray absorptiometry (DEXA) scanning and cross-sectional estimates of muscle mass are areas of active research and may play a future role in clinical risk-stratification.

"HIIT the Inflammation": Comparative Effects of Low-Volume Interval Training and Resistance Exercises on Inflammatory Indices in Obese Metabolic Syndrome Patients Undergoing Caloric Restriction

Exercise is a cornerstone in metabolic syndrome (MetS) treatment. However, the effects of low-volume exercise modalities on MetS-associated low-grade inflammation are unclear. A total of 106 MetS patients (53.7 ± 11.4 years) were randomized to low-volume high-intensity interval training (LOW-HIIT, 14 min/session), single-set resistance training (1-RT, ~15 min/session), whole-body electromyostimulation (WB-EMS, 20 min/session), three-set resistance training (3-RT, ~50 min/session), each performed 2 ×/week for 12 weeks, or a control group (CON). All groups received nutritional counseling for weight loss. Inflammatory and cardiometabolic indices were analyzed pre- and post-intervention. All groups significantly reduced body weight by an average of 3.6%. Only LOW-HIIT reduced C-reactive protein (CRP) (−1.6 mg/L, p = 0.001) and interleukin-6 (−1.1 pg/mL, p = 0.020). High-sensitivity CRP and lipopolysaccharide-binding protein decreased following LOW-HIIT (−1.4 mg/L, p = 0.001 and −2.1 ng/mL, p = 0.004) and 3-RT (−0.6 mg/L, p = 0.044 and −2.0 ng/mL, p < 0.001). MetS severity score improved with LOW-HIIT (−1.8 units, p < 0.001), 1-RT (−1.6 units, p = 0.005), and 3-RT (−2.3 units, p < 0.001). Despite similar effects on body weight, low-volume exercise modalities have different impact on inflammatory and cardiometabolic outcomes in MetS patients. LOW-HIIT has superior efficacy for improving inflammation compared to 1-RT and WB-EMS. Resistance-based exercise appears to require a higher volume to promote beneficial impact on inflammation.

Biological Response of Irisin Induced by Different Types of Exercise in Obese Subjects: A Non-Inferiority Controlled Randomized Study

Simple Summary

Among healthy male and female obese individuals undergoing a 12-week aerobic exercise program with either moderate intensity endurance or high-intensity interval training for losing weight, a reduction of circulating irisin was observed. Irisin is an important adipo-myokine implicated in the regulation of energy metabolism and cardiovascular health. Sex differences in the circulating levels of this biomarker have been previously reported and are likely related to the different anthropometric features between the sexes. A sex-specific modulation of circulating irisin levels should be further explored to tailor sex-specific training approaches for improving the cardiovascular health of obese subjects.

Abstract

Background: Weight loss through physical exercise is warranted among obese individuals. Recently, a greater benefit in cardiorespiratory fitness was achievable with high-intensity interval training (HIIT) as compared with moderate intensity continuous training. The beneficial effect of training on CV health might be related to a specific modulation of circulating irisin, an adypo-myokine implicated in the regulation of energy expenditure. Methods: The present study investigates the circulating plasma levels of irisin at baseline and in response to 12-week of training program either with HIIT or moderate-intensity continuous training (MICT) among young female and male obese subjects. Clinical, anthropometric, and training characteristics for each participant were available. A sex-disaggregated data for circulating plasma levels of irisin pre- and post-training are provided as well as an adjusted multivariate linear regression model to identify the determinants of post-training irisin levels. Results: Data from a total of 32 obese healthy individuals (47% female, mean age 38.7 years, mean BMI 35.6 kg/m²), randomized in a 1:1 manner to HIIT or MICT were analyzed. Circulating plasma levels of irisin similarly and significantly decreased in both MICT and HIIT interventional groups. Females had higher post-exercise irisin levels than males (6.32 [5.51–6.75] vs. 4.97 [4.57–5.72] μg/mL, p = 0.001). When stratified by an interventional group, a statistically significant difference was observed only for the MICT group (male, 4.76 [4.20–5.45] μg/mL vs. female 6.48 [4.88–6.84] μg/mL p = 0.03). The circulating post-training level of irisin was independently associated with post-training fat-free mass (β −0.34, 95% confidence interval, CI −0.062, −0.006, p = 0.019) in a model adjusted confounders. When female sex was added into the adjusted model, it was retained as the only factor independently associated with irisin levels (β 1.22, 95% CI, 0.50, 1.93, p = 0.002). Conclusions: In obese healthy subjects, circulating irisin levels were reduced in response to 12-weeks of exercise involving either HIIT or MICT. A sex-specific differences in circulating irisin levels at baseline and as biological response to chronic exercise was described. Sex-specific biological response of irisin to exercise should be further explored to tailor sex-specific training approaches for improving the cardiovascular health of obese healthy subjects.

Obesity paradox and aging: Visceral Adiposity Index and all-cause mortality in older individuals: A prospective cohort study

BACKGROUND

The relationship between body mass index (BMI) and mortality in older adults diminished. It is necessary to examine other factors that may accurately predict mortality in older adults. The visceral adiposity index (VAI) is an uncomplicated marker specific to the gender that incorporates anthropometric data and lipid profiles. VAI has been proposed as a marker of visceral adipose tissue dysfunction and of the related cardiometabolic risk. The aim of this study was to evaluate the link of VAI with all-cause mortality among the elderly.

METHODS

The present prospective cohort study included data from 1999 to 2014 provided by the National Health and Nutrition Examination Survey (NHANES) in the United States. NHANES participants at or above the age of 65 were included. Data collection was carried out by taking face-to-face interviews, mobile-physical examinations, and lab tests. From the start of the survey to the end of December 2015, mortality-related follow-up statistics are available. The shape of the link between VAI and all-cause mortality was investigated using a restricted cubic spline model. Univariate- and multivariate-adjusted Cox proportional hazard models were estimated for VAI, and the results were presented as regression coefficients and 95% confidence intervals (CI).

RESULTS

The 82,091 NHANES participants represented 442.2 million non-institutionalized residents of the United States. A total of 11,173 older individuals (representing 23.3 million; aged 73.4 ± 5.8 years; 56.3% women, 82.7% non-Hispanic Whites, 6.8% non-Hispanic Blacks, and 3.3% Mexican Americans) were included in the study. During the 80-month follow-up period, 4466 fatalities were reported, including 825 deaths from cancer, 867 from heart disease, and 211 from cerebrovascular disease. The restricted cubic spline model demonstrated a robust J-shaped link between VAI and all-cause mortality, revealing a significant decrease in risk within the lower range of VAI, which attained the lowest risk close to 1.7. With VAI greater than 1.7, the risk of mortality increased with the increase of VAI (P for non-linearity = 0.025). In the multivariate-adjusted model, the risk of all-cause mortality was 0.73 (0.56-0.97) and 1.05 (1.01-1.09) in participants with VAI less than 1.7 and VAI greater than or equal to 1.7, respectively.

CONCLUSION

This investigation is a population-based cohort study with high sample sizes and a long-term in older individuals follow-up that showed a J-shaped link between VAI levels and all-cause mortality. Understanding the independent roles of VAI in the relationship between BMI and mortality is crucial to understanding the obesity paradox phenomenon.

Effectiveness of high-intensity interval training for weight loss in adults with obesity: a randomised controlled non-inferiority trial

INTRODUCTION

Obesity treatment guidelines suggest moderate-intensity continuous training (MICT), but the patient's compliance to this indication remains low. High-intensity interval training (HIIT) is a time sparing training mode whose metabolic effects are not clear. This study aimed to determine whether a 12-week HIIT was more effective than MICT for weight loss in obese adults.

METHODS

44 obese subjects were randomised and trained with isoenergetic treadmill exercises for 12 weeks: MICT (60% of maximal oxygen peak, VO2peak) or HIIT (3-7 repetition of 3 min 100% of VO2peak interspersed by 1.5 min 50% of VO2peak). The primary outcome was a change in body weight; the secondary outcomes were changes in body composition, blood pressure, lipid profile, glycaemia, insulin and VO2peak.

RESULTS

32 subjects (53% male, mean age: 38.5 years, mean body mass index: 35.5 kg/m2) completed the trial. MICT and HIIT showed comparable effect within groups in weight loss (-6.0 kg (-9.0 kg to -3.0 kg) vs -5.7 kg (-8.3 kg to -3.1 kg)), changes in fat mass (-2.9% (-4.4% to -1.4%) vs -3.6% (-5.9% to -1.2%)), fat free mass (-5.3% (-7.8% to -2.8%) vs -5.5% (-8.3% to -2.6%)), diastolic blood pressure (-5.5 mm Hg (-10.6 mm Hg to -0.3 mm Hg) vs -5.8 mm Hg (-11.3 mm Hg to -0.3 mm Hg)) and low-density lipoprotein cholesterol (-16.4 mg/dL (-30.8 mg/dL to -2.0 mg/dL) vs -14.7 mg/dL (-25.6 mg/dL to -3.8 mg/dL)). There was a significant change between groups in VO2peak (HIIT: +461.6 mL (329.3‒593.8 mL); MICT: +170.5 mL (86.7-254.4 mL); p<0001) and duration of sessions (HIIT: 35.0 min (31.7 ‒35.6 min); MICT: 46.5 min (40.2‒48.3 min); p<0.001). No significant changes in systolic blood pressure, high-density lipoprotein cholesterol, triglycerides, glycaemia or plasma insulin were observed.

CONCLUSIONS

In healthy adults with obesity, HIIT compared with MICT induced similar weight loss and cardiovascular risk factors improvement but resulted in a larger increase in cardiorespiratory fitness over a shorter period.

Control of Adipose Cell Browning and Its Therapeutic Potential

Adipose tissue is the largest endocrine organ in humans and has an important influence on many physiological processes throughout life. An increasing number of studies have described the different phenotypic characteristics of fat cells in adults. Perhaps one of the most important properties of fat cells is their ability to adapt to different environmental and nutritional conditions. Hypothalamic neural circuits receive peripheral signals from temperature, physical activity or nutrients and stimulate the metabolism of white fat cells. During this process, changes in lipid inclusion occur, and the number of mitochondria increases, giving these cells functional properties similar to those of brown fat cells. Recently, beige fat cells have been studied for their potential role in the regulation of obesity and insulin resistance. In this context, it is important to understand the embryonic origin of beige adipocytes, the response of adipocyte to environmental changes or modifications within the body and their ability to transdifferentiate to elucidate the roles of these cells for their potential use in therapeutic strategies for obesity and metabolic diseases. In this review, we discuss the origins of the different fat cells and the possible therapeutic properties of beige fat cells.

Association of Fitness and Fatness with Clustered Cardiovascular Disease Risk Factors in Nigerian Adolescents

Purpose: This study examinedthe independent and joint association of fitness and fatness with clustered cardiovascular disease risk (CVDrs) in 11-18 year-old Nigerian adolescents. Methods: A hundred and ninety seven adolescents (100 girls and 97 boys) were evaluated forfitness, fatness and CVDrs. Fitness was evaluated with the progressive aerobic cardiovascular endurance run test while fatness was assessed using body mass index. A clustered CVDrs was computed from the standardized residuals of total cholesterol, high density lipoprotein cholesterol, Low density lipoprotein cholesterol, triglycerides, plasma glucose, systolic blood pressure, and diastolic blood pressure. Regression models controlling for waist circumference assessed the association of fitness and fatness with CVDrs. Results: Prevalence of clustered CVD risk was 7.1% (girls = 3.0%; boys = 4.1%). Based on risk factor abnormalities, 52.8% of participants had one or more CVD risk factor abnormalities with more boys (27.4%) affected. Low fitness was associated with clustered CVDrs in both girls (R2 = 9.8%, β = -0.287, p = 0.05) and boys (R2 = 17%, β = -0.406, p < 0.0005). Fatness was not associated with the CVDrs in both sexes. After controlling for all the variables in the model, only fitness (R2 = 10.4%) and abdominal fat (R2 = 19.5%) were associated with CVDrs respectively. Unfit girls were 3.2 (95% CI = 1.31-7.91, p = 0.011) times likely to develop CVD risk abnormality compared to their fit counterparts. The likelihood of unfit boys developing CVD risk abnormality was 3.9 (95% CI = 1.15-10.08, p = 0.005) times compared to their fit peers. Conclusions: Fitness but not fatness was a better predictor of CVDrs in Nigerian boys and girls. The result of this study suggests that any public health strategies aimed at preventing or reversing the increasing trends of CVD risk in adolescents should emphasize promotion of aerobic fitness.

Could Omega 3 Fatty Acids Preserve Muscle Health in Rheumatoid Arthritis?

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by a high prevalence of death due to cardiometabolic diseases. As observed during the aging process, several comorbidities, such as cardiovascular disorders (CVD), insulin resistance, metabolic syndrome and sarcopenia, are frequently associated to RA. These abnormalities could be closely linked to alterations in lipid metabolism. Indeed, RA patients exhibit a lipid paradox, defined by reduced levels of total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol whereas the CVD risk is increased. Moreover, the accumulation of toxic lipid mediators (i.e., lipotoxicity) in skeletal muscles can induce mitochondrial dysfunctions and insulin resistance, which are both crucial determinants of CVD and sarcopenia. The prevention or reversion of these biological perturbations in RA patients could contribute to the maintenance of muscle health and thus be protective against the increased risk for cardiometabolic diseases, dysmobility and mortality. Yet, several studies have shown that omega 3 fatty acids (FA) could prevent the development of RA, improve muscle metabolism and limit muscle atrophy in obese and insulin-resistant subjects. Thereby, dietary supplementation with omega 3 FA should be a promising strategy to counteract muscle lipotoxicity and for the prevention of comorbidities in RA patients.

Managing Risk of Non-Communicable Diseases in Women with Bulimia Nervosa or Binge Eating Disorders: A Randomized Trial with 12 Months Follow-Up

Persons with bulimia nervosa (BN) or binge eating disorder (BED) have an elevated risk of non-communicable diseases (NCDs). However, lowering this risk is rarely addressed in standard cognitive-behavioral treatment (CBT). We aimed to compare CBT with an intervention combining physical exercise and dietary therapy (PED-t), and hypothesized that the PED-t would do better than CBT in lowering the risk of NCD both initially and longitudinally. In this study, 164 women with bulimia nervosa or binge eating disorder were randomly assigned to 16-weeks of outpatient group therapy with either PED-t or CBT. Body composition (BC) was measured by dual-energy X-ray absorptiometry. Measures of physical fitness (VO₂peak and one repetition maximum (1RM) in squats, bench press, and seated row) were also recorded. All measurements were completed baseline, post-treatment, and at 6- and 12-month follow-ups, respectively. Our results showed that PED-t improved more than CBT on mean (99% CI) absolute Vo2peak; 57,2 (84.4, 198.8) mL (g = 0.22, p < 0.001) post-treatment. There were small to medium long-term differences in 1RM after PED-t compared to CBT. BC deteriorated in both groups during follow-up. Neither the PED-t nor the CBT lowered the risk for NCDs. Clearly, other approaches need to be considered to promote physical fitness and lower the risk of NCDs among individuals with BN and BED.