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Obesity represents a major health problem in the United States and is associated with increased prevalence of cardiovascular (CV) disease risk factors. Physical activity (PA) and exercise training (ET) are associated with reduced CV risk, improved cardiometabolic risk factors, and facilitated weight loss through creating a negative energy balance. Clinicians need to counsel overweight and obese patients on how much PA/ET is needed to promote weight loss and weight loss maintenance. This will help establish realistic expectations and maximize improvements in CV risk factors. Although the minimum guidelines for aerobic PA (150 min of moderate or 75 min of vigorous physical activity per week) can improve CV health, these levels are generally inadequate for clinically significant weight loss or weight maintenance without caloric restriction. The purpose of this review is to evaluate the role of ET to promote clinically significant weight loss and promote weight maintenance. In particular, we will evaluate the likelihood of weight loss from ET programs composed of aerobic training only, resistance training only and programs that combine diet and ET. We will also explore the role of PA in promoting short-term and long-term weight maintenance.

African Americans (AAs) have a higher risk for cardiovascular disease (CVD) compared to their Caucasian American (CA) counterparts, which represents a major health disparity. Low cardiorespiratory fitness (CRF) is a well-established independent risk factor for all-cause and CVD mortality, which has been shown across many epidemiological and clinical trials to be lower in AAs compared to CAs. While much attention has been given to traditional health disparity risk factors (e.g. blood pressure, obesity, insulin resistance), the impact of racial differences in CRF on CVD mortality has not been widely considered. Thus, the purpose of this paper is to review the literature on: 1) the magnitude of racial differences in CRF and the potential clinical significance, 2) examine the relationships between CRF and mortality in AAs and CAs, 3) Potential physiological and behavioral etiologies for racial difference in CRF, and 4) the impact of exercise training on CRF and other cardiometabolic risk factors in AAs compared to CAs. Given that both CRF and change in CRF are associated with reduced CVD mortality, advocating aerobic exercise training or moderate to vigorous activities in AAs has the potential to reduce racial cardiovascular health disparities.

Recent data has suggested that prolonged sedentary behavior is independent risk factor for cardiovascular and all-cause mortality independent of adequate amounts of moderate to vigorous physical activity. However, few studies have prospectively evaluated if exercise training and increasing non-exercise physical activity leads to greater reduction in cardiometabolic risk compared to aerobic training alone. The purpose of the Intervention Composed of Aerobic Training and Non-Exercise Physical Activity (I-CAN) study is to determine whether a physical activity program composed of both aerobic training (consistent with public health recommendations) and increasing non-exercise physical activity (3000 steps above baseline levels) leads to enhanced improvements in waist circumference, oral glucose tolerance, systemic inflammation, body composition, and fitness compared to aerobic training alone in obese adults (N=45). Commercially available accelerometers (Fitbits) will be used to monitor physical activity levels and behavioral coaching will be used to develop strategies of how to increase non-exercise physical activity levels. In this manuscript, we describe the design, rationale, and methodology associated with the I-CAN study.

High levels of obesity among African American women have been hypothesized to be partially resultant from a lower resting metabolic rate compared with white women. The aim of the current study was to determine if differences in cardiorespiratory fitness and moderate-to-vigorous physical activity are associated with differences in resting metabolic rate among free-living young adult African American women and white women.Participants were 179 women (white women n = 141, African American women n = 38, mean age = 27.7 years). Resting metabolic rate was measured using indirect calorimetry, body composition using dual energy x-ray absorptiometry, cardiorespiratory fitness via maximal treadmill test, and moderate-to-vigorous physical activity using an activity monitor.African American women had higher body mass index, fat mass, and fat-free mass compared with white women but lower levels of cardiorespiratory fitness. No differences were observed between African American and white women in resting metabolic rate when expressed as kcal/day (1390.8 ± 197.5 vs 1375.7 ± 173.6 kcal/day, P = .64), but African American women had a lower resting metabolic rate when expressed relative to body weight (2.56 ± 0.30 vs 2.95 ± 0.33 mL/kg/min, P.001). After statistical adjustment for differences in body composition between groups using linear regression models, African American women had a lower resting metabolic rate compared with white women (1299.4 ± 19.2 vs 1400.4 ± 9.2 kcal/day, P.001). The addition of cardiorespiratory fitness reduced the differences among groups by 25%. The addition of moderate-to-vigorous physical activity did not improve the model.The present study confirms that African American women have a lower resting metabolic rate compared with their white peers, and low cardiorespiratory fitness explained 25% of this difference. Variables associated with resting metabolic rate, such as cardiorespiratory fitness, represent possible points of tailored interventions designed to address high levels of obesity seen in certain demographic groups.

As an ancillary report to a large National Institutes of Health (NIH)–funded trial, we examined the effects of 6 months of exercise training at 50%, 100%, and 150% of the NIH Consensus Recommendations for physical activity (i.e., 4, 8, and 12 kcal/kg of energy expenditure/wk [KKW]) versus a nonexercise control group on the metabolic syndrome (MS) in sedentary, overweight, moderately hypertensive, postmenopausal women. We examined the clinically defined National Cholesterol Education Program MS, individual components scores, and summed z-scores, expressed as a continuous variable (zMS), using chi-square and general linear models to assess the clinical and progressive nature of MS, respectively. Our results showed significant improvements in zMS for all exercise groups and MS for the 8- and 12 KKW groups only (all, p for trend = 0.02). Post hoc analyses showed that 12 KKW for zMS and 8 and 12 KKW for MS was significant versus the control group (all, p

Background Exercise training reduces adiposity and risk of cardiovascular disease. However, the combined effects of habitual free-living physical activity and aerobic training on waist circumference, weight, fitness, and blood pressure in postmenopausal women are unknown. Purpose To evaluate the effects of habitual physical activity levels during aerobic training on weight, waist circumference, fitness, and blood pressure. Design Secondary analysis of an RCT. Original data collected April 2001 to June 2005 and analyzed in 2012. Setting/participants Postmenopausal women in a supervised exercise trial. Intervention Women ( n =325) were randomized to 4, 8, or 12 kcal/kg per week of aerobic training or a control group for 6 months. All outcome measures were collected at baseline and follow-up. Changes in dependent variables within each training group were evaluated across tertiles of pedometer-determined habitual physical activity outside exercise training sessions. Main outcome measures Changes in waist circumference and weight. Results Reductions in waist circumference were significantly greater with higher steps/day accumulated outside exercise training compared to lower levels in the 4 (high: −4.8 cm vs low: −1.4 cm, p =0.03); 8 (high: −4.2 cm vs low: −0.4 cm, p =0.03), and 12 kcal/kg per week groups (high: −4.1 cm vs low: −0.7 cm, p =0.05). For all groups, p -trend≤0.03. A trend was observed for greater weight reduction with higher steps/day in the 4 kcal/kg per week group ( p -trend=0.04) but not for the other exercise doses. No effects were observed for blood pressure or fitness measures (all p >0.05). Conclusions In postmenopausal women, higher habitual physical activity while participating in aerobic training was associated with greater reductions in central adiposity, and was supportive of weight loss compared to lower levels.

A significant heterogeneity in the cardiorespiratory fitness change in response to exercise training has been reported in well-controlled exercise trials [(1)][1]. However, the sources of this variability are not well understood. In this study, we sought to examine potential cardiac determinants