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PURPOSE Epidemiological studies suggest that sedentary behavior is an independent risk factor for cardiovascular mortality independent of meeting physical activity guidelines. However, limited evidence of this relationship is available from prospective interventions. The purpose of the present study is to evaluate the combined effect of aerobic training and increasing nonexercise physical activity on body composition and cardiometabolic risk factors. METHODS Obese adults (N = 45) were randomized to 6 months of aerobic training (AERO), aerobic training and increasing nonexercise physical activity (~3000 steps above baseline levels; AERO-PA), or a control (CON) group. The AERO and AERO-PA groups performed supervised aerobic training (3-4 times per week). The AERO-PA group wore Fitbit One accelerometers and received behavioral coaching to increase nonexercise physical activity. RESULTS There was a larger increase in fitness in the AERO-PA group (0.27 L·min-1; confidence interval (CI), 0.16 to 0.40 L·min-1) compared with the AERO group (0.09 L·min-1; CI, -0.04 to 0.22 L·min-1) and the CON group (0.01; CI, -0.11 to 0.12 L·min-1). Although significant findings were not observed in the entire study sample, when the analysis was restricted to participants compliant to the intervention (n = 33), we observed significant reductions in waist circumference, percent weight loss, body fat, 2-h glucose, and 2-h insulin in comparison to the CON group (P < 0.05), but not the AERO group. Furthermore, linear regression models showed that change in steps was associated with 21% and 26% of the variation in percent weight loss and percent fat loss, respectively. CONCLUSIONS Increasing nonexercise physical activity with aerobic training may represent a viable strategy to augment the fitness response in comparison to aerobic training alone and has promise for other health indicators.

There is limited evidence on the impact of weight loss via caloric restriction and aerobic exercise on Life’s Simple 7 (LS7), a health assessment tool used by the American Heart Association to promote and track cardiovascular health (CVH) via modifiable risk factors and health behaviors. Individuals with obesity have a greater prevalence of traditional and non-traditional cardiometabolic risk factors than lean individuals. Objective: Examine the effect of a weight loss intervention on LS7 and assess predictors of change in adults with obesity. Methods: Twenty-six adults (44.9 ± 9.7 years; weight: 93.9 ± 11.1 kg; body mass index: 34.1 ± 3.4 kg/m 2 ) participated in a 10-week medical weight loss program (OPTIFAST) and supervised exercise training program (50-75% VO 2 max) to achieve clinically significant weight loss (≥7% body weight). Poor, intermediate, and ideal CVH categories were defined as scores 0 to 4, 5 to 9, and 10 to 14, respectively. Baseline and post-weight loss LS7 scores were calculated via participant demographics, smoking status, anthropometry, physical activity level, diet intake, and blood lab reports. Paired samples t-test and Pearson’s correlations were used. Results: Mean weight loss was significant (-9.2 ± 3.6 kg, p < 0.001). Mean LS7 score significantly increased from baseline to weight loss (7.3 ± 1.5 vs. 9.6 ± 1.2, respectively, p < 0.001) and 57.7% of participants (15 of 26) improved to ideal CVH following weight loss. A significant inverse association was observed between change in LS7 and systolic blood pressure ( r = -0.41, p < 0.05), total cholesterol ( r = -0.45, p < 0.05), and glucose ( r = -0.41, p < 0.05). There were no further significant relationships with LS7 (i.e. change in weight, body mass index, physical activity, diastolic blood pressure). Discussion: A combined caloric restriction and aerobic exercise training intervention improved a multitude of cardiovascular disease risk factors. Previous epidemiological studies indicate meeting the ideal LS7 metrics is associated with 78% and 49% reduced risk of cardiovascular disease morbidity and mortality, respectively. Thus, the long-term modification of health behaviors and cardiometabolic risk factors to achieve ideal cardiovascular health may reduce risks of cardiovascular morbidity and mortality in individuals with obesity.

Objective: The OPTIFAST diet has known effects for weight loss, but little data exists on the effects of the diet on arterial stiffness. Methods: Overweight and obese (BMI: 34.5 + 4.0) adults (N=17) participated in a 10-week OPTIFAST™ weight loss program and supervised aerobic exercise training (50%-75% VO 2 max). The diet consisted of OPTIFAST meal replacement products with a goal of reducing total caloric intake to 800 kcals/day and attending a weekly weight management class. Aerobic exercise was performed 3 times per week and the exercise volume was progressed from 300 to 700 MET mins. per week at an intensity of 50%-75% VO2 max. The goal of study participants was to achieve a 7% weight loss. Carotid-to-femoral pulse wave velocity, blood pressure (aortic and brachial), vascular age, augmentation index and blood samples were measured in the morning after an overnight fast at baseline and follow-up. A paired t-test was performed to evaluate the change in outcomes variables. Results: The mean percent weight loss in the sample was 9.0% (-8.5 kg), with 83.3% of participants achieving 7% weight loss (94.1% achieving ≥5%). The adherence to the exercise program was 94.9% and attendance in the weight loss classes was 81.8%. There was a reduction in pulse wave velocity (-0.44 m/s, p=0.030), aortic systolic blood pressure (-10.5 mmHg, p0.05). Discussion: A hypo-caloric dietary program in combination with aerobic exercise training improves arterial stiffness, aortic blood pressure, and brachial blood pressure in overweight and obese adults An important limitation of the present study is that we cannot separate the health benefits of the diet from the exercise.

Introduction: Previous studies have shown that lipoprotein particle size and lipoprotein subclasses are associated with cardiovascular and type 2 diabetes risk, and have independent prognostic value above traditional lipid concentrations. The impact of exercise training and increasing non-exercise physical activity on lipoprotein subclasses and size has not been previously investigated. Methods: In this pilot study, 35 obese adults were randomized to aerobic exercise training (50-75% of VO 2 max) (AERO, n=11), aerobic training and increasing non-exercise physical activity (AERO-PA, n=10, ~3,000 steps above baseline levels), or a non-exercise control group (n=14) for 6 months. Baseline and follow-up blood samples were analyzed for lipoprotein subclass, size, and lipoprotein insulin resistance score (LP-IR) using nuclear magnetic resonance spectroscopy (Liposcience, NC). Analysis of covariance was used to evaluate the change in outcome variables following the intervention across groups with adjustment for baseline value and age. Participants who changed lipid medications during the intervention (n=2) or who were non-adherent to exercise training (n=2) were excluded from the analysis. Results: Significant reductions were observed for mean VLDL size in the AERO-PA group (-4.7 nm, CI: -8.7 to -0.8) compared to control group (0.7 nm, CI: -2.7 to 4.4) and the AERO group (1.1 nm, CI: -2.9 to 5.0). Reductions in triglyceride concentrations were observed in the AERO-PA group (-28.3 mg/dL, CI: -50.3 to -6.4) compared to control (4.1 mg/dL, CI: -14.6 to 22.8). Additionally, we observed a trend for LP-IR index (p=0.055) and the concentration of small HDL particles (p=0.093) to decrease in the AERO-PA group compared to controls, with no differences compared to the AERO group (p>0.10). No significant changes were observed for other notable lipoprotein measures, such as LDL size, HDL size, concentration of small LDL particles, or chylomicron measures (p>0.05). In the AERO-PA group, the change in steps was associated with the change in LP-IR index (r= -0.71, p=0.013), but not with change in VLDL size (r= -0.24, p=0.463) or triglyceride concentrations (r=-0.28, p=0.388). Conclusions: Aerobic training combined with increasing non-exercise physical activity leads to favorable changes in the lipoprotein profile, specifically reductions in VLDL size and triglycerides, and may have promise for other lipoprotein traits (reductions in LP-IR and small HDL particles) that were not observed with aerobic training alone.