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BACKGROUND: Little is known about predictors of activity participation that are objectively measured in cardiac rehabilitation (CR) graduates. This prospective observational study aimed to determine the predictors of objectively measured activity participation among adults with chronic cardiac conditions who have completed Phase II CR. METHODS: Twenty-five adults with chronic cardiac conditions graduating from traditional CR program participated in the study. The outcome variable was an activity participation level measured by light-to-vigorous intensity physical activity (LVPA) minutes using ActiGraph GT9X Link accelerometer after CR discharge. Covariates were collected at the discharge from CR, and outcome variables were collected at 1 month, 3 months, and 9 months post CR discharge. RESULTS: Gender, standardized LVPA at CR discharge, body mass index, and motivation for physical activity and leisure were significantly associated with the activity participation levels at 1 month, 3 months, and/or 9 months post CR discharge. Gender, standardized LVPA at CR discharge, highest education completed, and depressive symptoms significantly predicted the activity participation levels at 1 month (R2 = 0.69, p

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.

PURPOSE: To examine the impact of a community-based exercise training intervention on cardiometabolic outcomes in African American men who have a family history of type 2 diabetes. METHODS: The Aerobic Plus Resistance Training and Insulin Sensitivity in African American Men (ARTIIS) study randomized participants into either an exercise training intervention or an information only control group for 5 months. The exercise training intervention consisted of 150 minutes of moderate intensity aerobic activity and two days of resistance training per week, consistent with the current federal physical activity guidelines. Participants in the control group received monthly newsletters featuring topics focused heavily on type 2 diabetes education and prevention. Outcome data were analyzed using repeated measures analysis of covariance (ANCOVA) models and incorporating both intention-to-treat and per-protocol principles. RESULTS: Adherence to the aerobic and resistance training prescriptions were between 77% and 79%. Despite significant within group improvements in glucose and insulin levels (fasting, 2-hour, 2-hour minus baseline) and Homeostatic Model 2-Insulin Resistance, there were not significant between group differences. There was a marginally significant between group difference for Homeostatic Model 2-Beta (p < 0.06), and significant between group differences in peak cardiorespiratory fitness (p < 0.001) and waist circumference (p = 0.03). CONCLUSION: These findings suggest that exercise training in accordance with the current national recommendations is effective in improving some health parameters in middle-aged African American men who have a family history of type 2 diabetes, but did not have a significant impact on glycemic status. TRIAL REGISTRATION: The study is registered in clinicaltrials.gov [].

Background: Step-counting interventions with discrepant intensity emphases may elicit different effects. Methods: A total of 120 sedentary/low-active, postmenopausal women were randomly assigned to one of the following 3 groups: (1) 10,000 steps per day (with no emphasis on walking intensity/speed/cadence; basic intervention, 49 completers), (2) 10,000 steps per day and at least 30 minutes in moderate intensity (ie, at a cadence of at least 100 steps per minute; enhanced intervention, 47 completers), or (3) a control group (19 completers). NL-1000-determined steps and active minutes (a device-specific indicator of time at moderate+ intensity) were collected as process variables during the 12-week intervention. Outcome variables included systolic and diastolic blood pressure, anthropometric measurements, fasting blood glucose and insulin, flow-mediated dilation, gait speed, and ActiGraph GT3X+-determined physical activity and sedentary behavior. Results: The “basic group” increased 5173 to 9602 steps per day and 9.2 to 30.2 active minutes per day. The “enhanced group” similarly increased 5061 to 10,508 steps per day and 8.7 to 38.8 active minutes per day. The only significant change over time for clinical variables was body mass index. Conclusions: Interventions that use simple step-counters can achieve elevated volume and intensity of daily physical activity, regardless of emphasis on intensity. Despite this, few clinical outcomes were apparent in this sample of postmenopausal women with generally normal or controlled hypertension.

Objective This study examined relationships between specific types of physical activity (PA) and motor skill development in preschool-aged children. Design This study was completed using a cross-sectional study design. Methods Data from children 3−5 years old (N = 342, 51% males) who participated in the 2012 National Youth Fitness Survey were analyzed. PA was measured using a questionnaire by parent report and motor skill development determined by Test of Gross Motor Development-2nd Edition (TGMD-2). Multiple regression analyses were conducted to examine the relationship between PA type and overall Gross Motor Quotient (GMQ) controlling for age, sex, race, and parental socioeconomic status. Results Commonly reported activities were running (43%), playing outdoor games (35%), and riding a bike (34%). Based on the standard scores, participants’ motor skill development for Locomotor, Object Control, and overall GMQ were considered average. Participation in the following physical activities were positively associated with GMQ: riding a bike (β (SE) = 5.27 (2.02), p = 0.02), scooter riding (β (SE) = 9.83 (2.59), p = 0.002), swimming (β (SE) = 4.01 (1.17), p = 0.004), and jumping on a trampoline (β (SE) = 7.45 (3.09), p = 0.03). With the exception of riding a bike, the physical activities positively related to GMQ had a reported range of participation between 7–12%. Conclusions Participation in specific physical activities was related to higher GMQ in preschool-aged children. Also, with the exception of riding a bike, the activities that the children participated in the most were not the same as the activities that were positively related to motor skill development.

The combination of aerobic and resistance training (AER + RES) is recommended by almost every major organization to improve health-related risk factors associated with sedentary behavior. Since the release of the Physical Activity Guidelines for Americans in 2008, several large well-controlled trials and ancillary reports have been published that provide further insight into the effects of AER + RES on health-related outcomes. The current manuscript examines the literature on the effects of AER + RES on major clinical outcomes, including glucose homeostasis, cardiorespiratory fitness (CRF), and muscular strength, as well as other important clinical outcomes, including metabolic syndrome, hypertension, dyslipidemia, and quality of life. Collectively, research suggests that AER + RES and AER or RES alone improves glycemic control and insulin sensitivity compared with continued sedentary behavior. Significant changes in CRF are also observed, suggesting a reduction in cardiovascular disease-related mortality risk. Reduced adiposity, especially abdominal adiposity, and increased strength may also interact with CRF to promote additional health benefits associated with AER + RES. While findings from our review support current physical activity guidelines, a paucity of research limits the generalizability of the results.

Irisin is a recently discovered myokine that increases adipocyte metabolism, induces further "browning" of white adipose tissue, and enhances glucose metabolism. No study has ever determined how an acute bout of exercise impacts immediate post-exercise irisin concentration using a meta-analytic approach. The purpose of this study is to determine the impact of an acute bout of exercise on the magnitude of post-exercise irisin concentration in adults using meta-analytic procedures. Searches were performed on PubMed, EMBASE, CINAHL, PEDro, SCOPUS, and SPORTDiscus databases. Effect summaries were obtained using random-effects models. Random-effects single and multiple meta-regressions were performed to determine relationships between, and potential confounding effects of, variables of interest. Ten articles were retained for the final meta-analysis, producing 21 study estimates. An acute bout of exercise was accompanied by a post-exercise average increase in irisin concentration of 15.0 (95% CI: 10.8%-19.3%). There was no significant relationship between post-exercise irisin concentration and age, intensity of aerobic exercise, or type of exercise training session (resistance vs aerobic training). Fitness level and body mass index were identified as significant predictive variables for post-exercise irisin concentration. However, a multiple meta-regression model identified fitness level as the single best predictor, with being fit (21.1%±2.2%) associated with a nearly twofold increase in post-exercise irisin concentration, compared with being unfit (11.8%±2.1%). Immediately following an acute bout of exercise, irisin concentration increases substantially in adults, with fitness level as an important modifier for the effect.

Concomitant type 2 diabetes (T2D) and metabolic syndrome exacerbates mortality risk; yet, few studies have examined the effect of combining (AER+RES) aerobic (AER) and resistance (RES) training for individuals with T2D and metabolic syndrome. Methods: We examined AER, RES, and AER + RES training (9 months) commensurate with physical activity guidelines in individuals with T2D (n = 262; 63% female, 44% black). Primary outcomes were change in, and prevalence of, metabolic syndrome score at follow-up (mean and 95% confidence interval [CI]). Secondary outcomes included maximal cardiorespiratory fitness (V·O2peak) and estimated METs from time-to-exhaustion (TTE) and exercise efficiency calculated as the slope of the line between ventilatory threshold, respiratory compensation, and maximal fitness. General linear models and bootstrapped Spearman correlations were used to examine changes in metabolic syndrome associated with training primary and secondary outcome variables. Results: We observed a significant decrease in metabolic syndrome scores (P for trend = 0.003) for AER (-0.59, 95% CI = -1.00 to -0.21) and AER + RES (-0.79, 95% CI = -1.40 to -0.35), both being significant (P P < 0.05), which was more strongly related to TTE (25%–30%;r = -0.38, 95% CI = -0.55 to -0.19) than V·O2peak (5%–6%; r = -0.24, 95% CI = -0.45 to -0.01). Conclusions: AER and AER + RES training significantly improved metabolic syndrome scores and prevalence in patients with T2D. These improvements appear to be associated with improved exercise efficiency and are more strongly related to improved TTE versus V·O2peak.

Low cardiorespiratory fitness (CRF) is a well-established risk factor for all-cause and cardiovascular disease mortality. African Americans have higher rates of cardiovascular disease compared with their Caucasian counterparts. However, the extent to which lower CRF levels contribute to the excess risk in African Americans has not been fully explored. The purpose of this review is to: (i) explore the literature evaluating the relationship between CRF and mortality specifically in African American populations; and (ii) critically evaluate the studies which have compared CRF between African American and Caucasians in epidemiological studies and clinical trials. We have further discussed several potential mechanisms that may contribute to the observation of lower CRF levels in African American compared with Caucasian adults, including potential racial differences in physical activity levels, muscle fiber type distribution, and hemoglobin levels. If lower CRF is generally present in African Americans compared with Caucasians, and is of a clinically meaningful difference, this may represent an important public health concern.

OBJECTIVES: The aim of this study was to examine the effect of three different doses of aerobic exercise training (corresponding to approximately 50%, 100% and 150% of the National Institutes of Health consensus guidelines) on endothelial function in sedentary obese postmenopausal women with elevated blood pressure. Aerobic exercise training improves endothelial function in individuals with cardiovascular risk; however, it is unknown whether these adaptations occur in a dose-dependent manner. METHODS: Obese postmenopausal women (n=155) with elevated blood pressure (systolic blood pressure between 120 and 159.0 mm Hg) were randomly assigned to one of four groups: 4, 8 or 12 kilocalories per kilogram of energy expenditure per week (kcal/kg/week) or a non-exercise control group for 6 months. Endothelial function was assessed via flow-mediated dilation (FMD) at baseline and post-intervention. RESULTS: After exercise training, there was a similar improvement (1.02–1.5%) in FMD in all three exercise groups (p

The metabolic syndrome is a complex clustering of metabolic defects associated with physical inactivity, abdominal adiposity, and aging.To examine the effects of exercise training intensity on abdominal visceral fat (AVF) and body composition in obese women with the metabolic syndrome.Twenty-seven middle-aged obese women (mean +/- SD; age = 51 +/- 9 yr and body mass index = 34 +/- 6 kg x m(-2)) with the metabolic syndrome completed one of three 16-wk aerobic exercise interventions: (i) no-exercise training (Control): seven participants maintained their existing levels of physical activity; (ii) low-intensity exercise training (LIET): 11 participants exercised 5 d x wk(-1) at an intensityor = lactate threshold (LT); and (iii) high-intensity exercise training (HIET): nine participants exercised 3 d x wk(-1) at an intensityLT and 2 d x wk(-1)or = LT. Exercise time was adjusted to maintain caloric expenditure (400 kcal per session). Single-slice computed tomography scans obtained at the L4-L5 disc space and midthigh were used to determine abdominal fat and thigh muscle cross-sectional areas. Percent body fat was assessed by air displacement plethysmography.HIET significantly reduced total abdominal fat (P0.001), abdominal subcutaneous fat (P = 0.034), and AVF (P = 0.010). There were no significant changes observed in any of these parameters within the Control or the LIET conditions.The present data indicate that body composition changes are affected by the intensity of exercise training with HIET more effectively for reducing total abdominal fat, subcutaneous abdominal fat, and AVF in obese women with the metabolic syndrome.

Low serum bilirubin levels have been associated with increased risk for cardiovascular disease, and recent data suggest that lower body fat and reductions in weight are associated with higher bilirubin levels. However, it is unknown if exercise training can increase bilirubin levels and whether a higher dose of exercise will further increase bilirubin levels compared with a lower dose.The primary aim of our current report was to examine whether exercise dose affects bilirubin levels in obese postmenopausal women from the Dose-Response to Exercise in Women trial. In addition, we evaluated whether changes in fitness, insulin sensitivity, and waist circumference associated with exercise training were associated with change in bilirubin levels.Participants (n = 419) were randomized to the control group or to 4, 8, and 12 kcal·kg⁻¹·wk⁻¹ (KKW) of exercise training at an intensity of 50% of aerobic capacity. Total bilirubin levels were evaluated at baseline and at follow-up.Exercise training significantly increased serum bilirubin levels only in the 12-KKW group (0.044 mg·dL⁻¹, P = 0.026) compared with the control group (0.004 mg·dL⁻¹). Subgroup analyses showed that there was a significant increase in bilirubin levels in participants in the 12-KKW group (0.076 mg·dL⁻¹) who were classified as insulin resistant (homeostatic model assessment for insulin resistance score2.6) compared with insulin-resistant control participants (0.018 mg·dL⁻¹, P = 0.028).Our findings suggest that high doses of exercise training are necessary to significantly increase bilirubin levels in previously sedentary postmenopausal women and especially those with impaired glucose metabolism.