Maeng-Kyu Kim

Aerobic exercise training reduces epicardial fat in obese men

The purpose of this study was to determine the effects of exercise training on ventricular epicardial fat thickness in obese men and to investigate the relationship of the change in epicardial fat thickness to changes in abdominal fat tissue following exercise training. Twenty-four obese middle-aged men [age, 49.4 +/- 9.6 yr; weight, 87.7 +/- 11.2 kg; body mass index (BMI), 30.7 +/- 3.3 kg/m(2); peak oxygen consumption, 28.4 +/- 7.2 ml.kg(-1).min(-1); means +/- SD] participated in this study. Each participant completed a 12-wk supervised exercise training program (60-70% of the maximal heart rate; 60 min/day, 3 days/wk) and underwent a transthoracic echocardiography. The epicardial fat thickness on the free wall of the right ventricle was measured from both parasternal long- and short-axis views. The visceral adipose tissue (VAT) and subcutaneous adipose tissues were measured by computed tomography. Following exercise training, the epicardial fat thickness was significantly decreased (P < 0.001). The percentage change of epicardial fat thickness was twice as high compared with those of waist, BMI, and body weight of original values (P <0.05). There was a significant relationship (r = 0.525, P = 0.008) between changes in the epicardial fat thickness and VAT with exercise training. Stepwise multiple regression analysis revealed that the change in VAT, change in systolic blood pressure, and change in quantitative insulin sensitivity check index were independently related to the change epicardial fat thickness (P < 0.05). The ventricular epicardial fat thickness is reduced significantly after aerobic exercise training and is associated with a decrease in VAT. These results suggest that aerobic exercise training may be an effective nonpharmacological strategy for decreasing the ventricular epicardial fat thickness and visceral fat area in obese middle-aged men.

Comparison of epicardial, abdominal and regional fat compartments in response to weight loss

BACKGROUND AND AIMS Echocardiographic measurement of epicardial fat (EF) seems to be a reliable and diagnostic marker of visceral adipose tissue (VAT). However, the weight loss-induced changes in EF have not been compared with those in VAT or the truncal depot. In this study, we aimed to compare the weight loss-induced changes in EF, VAT and other regional fat compartments in obese men. METHODS AND RESULTS In this study, 27 moderately obese men (age 45.8+/-1.7 years; body mass index 30.5+/-0.7 kg/m(2)) followed a daily low-calorie diet as part of a clinical 12-week weight loss interventional study. We evaluated the EF thickness by transthoracic echocardiography, assessed the abdominal fat tissues by computed tomography scans, and examined the regional and whole body fat compartments by dual X-ray absorptiometry. An average decrease of 26.8% in the initial calorie intake corresponded to post-program reductions of 17.2%, 11.0%, 16.6%, and 29.8% in EF thickness (P<0.001), body mass, percentage fat mass, and abdominal fat compartments, respectively. The percentage change in VAT in response to weight loss was twice as high as the substantial change in EF tissue (P<0.001). CONCLUSION The results of the study suggest that a low-calorie diet-induced weight loss decreases EF thickness. Moderate diet-induced weight loss alone may represent an effective nonpharmacological strategy for reducing EF, which is a unique, pathogenic fat depot and an emerging marker of VAT.

Effect of Habitual Aerobic Exercise on Body Weight and Arterial Function in Overweight and Obese Men

The effect of habitual exercise on vascular function, including central arterial distensibility and endothelial function, in obese subjects has not yet been clarified. We investigated whether aerobic exercise training affects central arterial distensibility and endothelial function in middle-age overweight and obese men. A total of 21 overweight and obese men (age 50 +/- 2 years, body mass index 30 +/- 1 kg/m(2)) completed a 12-week aerobic exercise intervention. Aerobic exercise training significantly reduced their body weight and resulted in a significant decrease in body mass index. After the weight-reduction exercise program, carotid arterial compliance (determined by simultaneous B-mode ultrasonography and arterial applanation tonometry on the common carotid artery) significantly increased; and the beta-stiffness index, an index of arterial compliance adjusted for distending pressure, significantly decreased. The concentrations of plasma endothelin-1, a potent vasoconstrictor peptide produced by vascular endothelial cells, significantly decreased and plasma nitric oxide (measured as the stable end product [nitrite/nitrate]), a potent vasodilator produced by vascular endothelial cells, significantly increased after the weight-reduction exercise program. In conclusion, weight reduction by aerobic exercise training in overweight and obese men increased the central arterial distensibility. This increase might contribute to the improvement in endothelial function, as assessed by a decrease in endothelin-1 and an increase in nitric oxide, after exercise training-induced weight loss.

Alternative items for identifying hierarchical levels of physical disability by using physical performance tests in women aged 75 years and older.

Aim:  To identify individuals at hierarchical levels of physical disability by using physical performance tests and to determine threshold values for the discriminating of levels of physical disability in women aged 75 years or older.

Mobility performance tests for discriminating high risk of frailty in community-dwelling older women

We aimed to compare and identify high and low risk of frailty in community-dwelling older women by using five mobility performance tests. The participants were 166 older women at high risk and 171 age-matched controls at low risk of frailty according to the long-term care insurance (LTCI) system (age: 65-90 years). The mobility performance tests included 5-chair sit-to-stand (STS), alternate step, timed up-and-go (TUG), timed rapid gait (TRG), and usual gait speed (UGS). Data analysis showed that high-risk individuals (81.9%) were more likely to be pre-frail than low-risk individuals (55.0%) by Frieds frailty phenotype. The four mobility performance tests, except the 5-chair STS, had the largest areas under the curve (AUC) for discriminating older women at high and low risk (AUC>0.80, p<0.001). The optimal cutpoint (6 s) for the TRG test had the highest sensitivity (78%) and specificity (83%) in identifying high risk of frailty. Our results suggest that walking ability tests are clinically useful in screening older individuals at high risk of frailty. In particular, the TRG test is more likely than other tests to discriminate older women at high risk of frailty based on the LTCI system.

PPARG Genotype Accounts for Part of Individual Variation in Body Weight Reduction in Response to Calorie Restriction

Several studies indicate that expression of the peroxisome proliferator–activated receptor γ (PPARG) gene is influenced by calorie restriction. The aim of this study was to investigate whether PPARG gene variations are associated with weight reduction and changes in coronary heart disease (CHD) risk factors in response to a 14‐week calorie restriction. In total, 95 middle‐aged, Japanese women (BMI ≥25 kg/m2) enrolled as subjects for 14 weeks and attended weekly dietary lectures instructing them on how to consume a nutritionally balanced diet of 1,200 kcal/day. Eight single‐nucleotide polymorphisms (SNPs) in the PPARG gene (rs1801282 (Pro/Ala), rs2292101, rs2959272, rs1386835, rs709158, rs1175540, rs1175544, and rs1797912) were analyzed. Body weight decreased significantly (−7.7 ± 3.1 kg; −11.3 ± 4.4%) during the intervention. Six PPARG SNPs (rs2959272, rs1386835, rs709158, rs1175540, rs1175544, and rs1797912) were significantly associated with the weight reduction, with rs1175544 having the strongest association (P = 0.004). No differences across the rs1175544 genotypes were observed in any of the blood analyses or in blood pressure. In a multiple regression analysis, the rs1175544 genotypes accounted for 7% of the total weight reduction variance. These data suggest that one SNP of the PPARG genotype accounted for a significant portion of the total body weight reduction variance in response to a short‐term intervention consisting of calorie restriction; however, no relationship was found between these SNPs and the changes in CHD risk factors which accompanied weight loss.

Validation of lower extremity performance tests for determining the mobility limitation levels in community-dwelling older women

Background and aims: Assessment of mobility status among community-dwelling older people is important for preventing further deterioration of mobility and identifying changes in mobility as early as possible. We attempted to identify the optimal cut-off values for eight lower extremity performance (LEP) tests in community-dwelling older women with mobility limitation (ML) levels. Methods: The ML levels of 433 community-dwelling older women, mean age 73.2 years (SD 5.7, range 65–93) were classified according to self-reports. ML levels were identified by face-to-face interviews and according to self-reported difficulty in walking one-quarter of a mile or climbing 10 steps without resting. The LEP tests comprised one-legged stance, tandem stance, functional reach, tandem walk, alternate step, five chair sit-to-stands, timed up-and-go (TUG) and usual gait speed. Receiver-operating characteristic curves were obtained for all scales to assess optimal cut-off values. Results: The optimal cut-off value of 6.52 (s) for the TUG test was shown by the highest sensitivity (74%) and specificity (71%) in the discrimination of no ML from moderate ML, whereas the optimal cut-off value of 1.05 (m/s) in the usual gait speed test showed the highest sensitivity (73%) and specificity (67%) in the discrimination of moderate ML from severe ML. Conclusions: Among community-dwelling older women, TUG and usual gait speed had the highest sensitivity and specificity in discriminating ML levels.

Indirect lifestyle intervention through wives improves metabolic syndrome components in men

Objectives:It is well known that body weight loss through a direct (supervised) lifestyle intervention (LSI) improves obesity-related metabolic disorders. The purpose of this study was to investigate the effects of an indirect LSI on weight loss and metabolic syndrome (MetS) in spouses of LSI participants.Methods:A total of 104 men (abdominal circumference⩾85 cm; age, 52.1±9.3 years) were assigned to one of three groups: no intervention (NI, n=34), direct intervention (DI, n=34) or indirect intervention (II, n=36), the last of which consisted of subjects who did not participate in the direct LSI but whose wives did. Body weight and MetS components were measured before and after a 14-week intervention. Daily energy intake and activity-related energy expenditure were assessed before and during the intervention. The LSI program was mainly consisted of dietary modifications with a physical activity program.Results:No differences were observed across the three groups in any of the measures at baseline. Significant differences were observed among the groups in weight loss (NI, −0.7±1.4; DI, −6.2±3.3 and II, −4.4±3.7 kg) during the intervention. Along with the body weight reductions, significant improvements were observed in most of MetS components within the DI and II groups. When analyzing the spouse pairs in group II, significant correlations were observed in weight loss (r=0.57) and decreased total energy intake (r=0.54) between wives and husbands.Conclusions:Indirect LSI in abdominally obese men whose wives were undergoing LSI led to loss of weight and a decreased incidence of MetS, suggesting that indirect LSI may be an effective program for eliciting beneficial change in health status.

An increase in high-density lipoprotein cholesterol after weight loss intervention is associated with long-term maintenance of reduced visceral abdominal fat

Objectives:It is generally agreed that excess abdominal fat, in particular visceral abdominal fat (VAF), is related to an increased risk for obesity-related complications. We examined the association between metabolic risk factors and maintaining VAF after weight loss intervention.Methods:A total of 54 postmenopausal, obese women who achieved a VAF loss of at least 10% from their baseline values during a 14-week intervention were enrolled as subjects. Body weight, VAF assessed by CT scans, and metabolic risk factors (that is, blood pressure, lipids and glucose) were measured at baseline (week 0), post-intervention (week 15), and at a 2-year follow-up (week 105). The subjects were divided into two groups according to their changes in VAF between weeks 15 and 105 (follow-up period): (1) VAF gainers (VAF changes >0 cm2, n=28) or (2) VAF maintainers (VAF changes ⩽0 cm2, n=26).Results:The mean change in VAF of all subjects during the 14-week intervention was −34±16 cm2 (−29.7±12.3%) (P<0.01). Along with this change, improvements (P<0.05) were observed in all metabolic risk factors except for high-density lipoprotein cholesterol (HDLC). During the follow-up period, there were interactions between the two VAF groups in HDLC, triglycerides (TG) and total cholesterol (TC)/HDLC ratio (all P<0.01). In particular, the HDLC of VAF maintainers improved, and the value at week 105 exceeded baseline level (P<0.01). However, systolic and diastolic blood pressure, TC and low-density lipoprotein cholesterol in the VAF maintainers increased (all P<0.05) back to their mean baseline level despite a further decrease in their VAF during the follow-up period (P<0.01).Conclusions:This study shows that long-term maintenance of VAF after weight loss intervention is associated with improvements in HDLC and TG among obese, postmenopausal women.

Epicardial Fat Tissue: Relationship with Cardiorespiratory Fitness in Men

PURPOSE To explore the influence of the epicardial fat (EF) tissue on aspects of heart rate recovery (HRR) and cardiorespiratory fitness (V O2peak) in middle-aged men. METHODS A cross-sectional analysis of EF thickness was performed on 101 overweight or obese men. The men were categorized into low-EF, moderate-EF, and high-EF groups on the basis of ventricular EF thickness, as measured by transthoracic echocardiography. V O2peak was assessed with a graded maximal cycle ergometric test, including measurement of HRR 2 min after test cessation to estimate parasympathetic activity, with assessment of several metabolic parameters. RESULTS Men in the highest and the middle EF thickness tertile had significantly slower recovery times than subjects in the lowest tertile, respectively (P < 0.05). Subjects with higher EF thickness were more likely to have impaired recovery and to reveal lower cardiorespiratory fitness than low-EF group subjects. There was a significant partial correlation, adjusted by age and body weight, between EF thickness and V O2peak (r = -0.25, P = 0.014). In the hierarchical multiple linear regression analyses, EF thickness was the strongest predicting variable associated with V O2peak in these population (beta = -1.182, P = 0.001). CONCLUSIONS Higher EF thickness in men is associated with lower HRR at 1 and 2 min, a representation of autonomic dysfunction and poor cardiorespiratory fitness. These data suggest that moderately obese men with thicker EF tissue demonstrate reduced cardiorespiratory fitness and a differing parasympathetic response to exercise testing, as compared with men with lower EF levels.