Obesity and cardiovascular diseases: implications regarding fitness, fatness, and severity in the obesity paradox

Obesity has been increasing in epidemic proportions, with a disproportionately higher increase in morbid or class III obesity, and obesity adversely affects cardiovascular (CV) hemodynamics, structure, and function, as well as increases the prevalence of most CV diseases. Progressive declines in physical activity over 5 decades have occurred and have primarily caused the obesity epidemic. Despite the potential adverse impact of overweight and obesity, recent epidemiological data have demonstrated an association of mild obesity and, particularly, overweight on improved survival. We review in detail the obesity paradox in CV diseases where overweight and at least mildly obese patients with most CV diseases seem to have a better prognosis than do their leaner counterparts. The implications of cardiorespiratory fitness with prognosis are discussed, along with the joint impact of fitness and adiposity on the obesity paradox. Finally, in light of the obesity paradox, the potential value of purposeful weight loss and increased physical activity to affect levels of fitness is reviewed

Ejercicio dosis-respuesta de la pendiente V? E / V?CO 2 en mujeres posmenopáusicas en el estudio DREW

Purpose: Being overweight/obese, having hypertension, and being postmenopausal are risk factors for the development of congestive heart failure (CHF). A characteristic of CHF is an abnormal V?E/V?CO2 slope, which is predictive of mortality in patients with CHF. Although the V?E/V?CO2 slope is well established in CHF patients, little is known regarding interventions for 'at-risk' populations. Methods: We examined the V?E/V?CO2 slope in 401 sedentary, overweight, moderately hypertensive women randomized to 6 m of nonexercise (control) or 4 kcal·kg?1·wk?1 (KKW), 8 KKW, or 12 KKW of exercise at an intensity corresponding to 50% of baseline V?O2max. We examined trends in exercise treatment dose versus change in mean V?E/V?CO2 slope using a linear regression model (KKW vs V?E/V?CO2 slope) and a linear mixed model. Results: Regression analysis showed a significant trend for a reduction in the V?E/V?CO2 slope from baseline (mean ± SD: 32.6 ± 6.3; P < 0.004). When expressed as mean change (95% confidence interval (CI)) from baseline, we observed significant reductions in the V?E/V?CO2 slope for the 8-KKW (?1.14; 95% CI, ?1.5 to ?0.2) and 12-KKW (?1.67; 95% CI, ?2.3 to ?0.3) groups. No significant effect was noted for the 4-KKW (?0.4; 95% CI, ?1.2 to 0.15) group. Conclusion: Moderate-intensity aerobic exercise at doses of 8 KKW or greater seems to present an adequate dose of exercise to promote small but significant reductions in the V?E/V?CO2 slope in postmenopausal women who exhibit risk factors associated with the development of CHF

Heart Rate Variability and Exercise in Aging Women

Background: Our group has shown a positive dose-response in maximal cardiorespiratory exercise capacity (VO2max) and heart rate variability (HRV) to 6 months of exercise training but no improvement in VO2max for women ≥60 years. Here, we examine the HRV response to exercise training in postmenopausal women younger and older than 60 years. Methods: We examined 365 sedentary, overweight, hypertensive, postmenopausal women randomly assigned to sedentary control or exercise groups exercising at 50% (4 kcal/kg/week, [KKW]), 100% (8 KKW) and 150% (12 KKW) of the National Institute of Health (NIH) Consensus Development Panel physical activity guidelines. Primary outcomes included time and frequency domain indices of HRV. Results: Overall, our analysis demonstrated a significant improvement in parasympathetic tone (rMSSD and high frequency power) for both age strata at 8 KKW and 12 KKW. For rMSSD, the age-stratified responses were: control, \u3c60 years, 0.20 ms, 95% confidence interval (CI) - 2.40, 2.81; ≥60 years, 0.07 ms, 95% CI - 3.64, 3.79; 4 KKW, \u3c60 years, 3.67 ms, 95% CI 1.55, 5.79; ≥60 years, 1.20 ms, 95% CI - 1.82, 4.22; 8-KKW, \u3c60 years, 3.61 ms, 95% CI 0.88, 6.34; ≥60 years, 5.75 ms, 95% CI 1.89, 9.61; and 12-KKW, \u3c60 years, 5.07 ms, 95% CI 2.53, 7.60; ≥60 years, 4.28 ms, 95% CI 0.42, 8.14. Conclusions: VO2max and HRV are independent risk factors for cardiovascular disease (CVD) mortality. Despite no improvement in VO2max, parasympathetic indices of HRV increased in women ≥60 years. This is clinically important, as HRV has important VCD risk and neurovisceral implications beyond cardiorespiratory function

Associations Between Cardiorespiratory Fitness and C-Reactive Protein in Men

Objective - This study examined the association between cardiorespiratory fitness and C-reactive protein (CRP), with adjustment for weight and within weight categories. Methods and Results - We calculated median and adjusted geometric mean CRP levels, percentages of individuals with an elevated CRP (≥2.00 mg/L), and odds ratios of elevated CRP across 5 levels of cardiorespiratory fitness for 722 men. CRP values were adjusted for age, body mass index, vitamin use, statin medication use, aspirin use, the presence of inflammatory disease, cardiovascular disease, and diabetes, and smoking habit. We found an inverse association of CRP across fitness levels (P for trend\u3c0.001), with the highest adjusted CRP value in the lowest fitness quintile (1.64 [1.27 to 2.11] mg/L) and the lowest adjusted CRP value in the highest fitness quintile (0.70 [0.60 to 0.80] mg/L). Similar results were found for the prevalence of elevated CRP across fitness quintiles. We used logistic regression to model the adjusted odds for elevated CRP and found that compared with the referent first quintile, the second (odds ratio [OR] 0.43, 95% CI 0.22 to 0.85), third (OR 0.33, 95% CI 0.17 to 0.65), fourth (OR 0.23, 95% CI 0.12 to 0.47), and fifth (OR 0.17, 95% CI 0.08 to 0.37) quintiles of fitness had significantly lower odds of elevated CRP. Similar results were found when examining the CRP-fitness relation within categories of body fatness (normal weight, overweight, and obese) and waist girth (\u3c102 or ≥102 cm). Conclusions - Cardiorespiratory fitness levels were inversely associated with CRP values and the prevalence of elevated CRP values in this sample of men from the Aerobics Center Longitudinal Study

Longitudinal algorithms to estimate cardiorespiratory fitness: associations with nonfatal cardiovascular disease and disease-specific mortality

Objectives This study sought to determine the capacity of cardiorespiratory fitness (CRF) algorithms without exercise testing to predict the risk for nonfatal cardiovascular disease (CVD) events and disease-specific mortality. Background Cardiorespiratory fitness (CRF) is not routinely measured, as it requires trained personnel and specialized equipment. Methods Participants were 43,356 adults (21% women) from the Aerobics Center Longitudinal Study, followed up between 1974 and 2003. Estimated CRF was determined on the basis of sex, age, body mass index, waist circumference, resting heart rate, physical activity level, and smoking status. Actual CRF was measured by a maximal treadmill test. Risk reduction per 1-metabolic equivalent increase, discriminative ability (c statistic), and net reclassification improvement were determined. Results During a median follow-up of 14.5 years, 1,934 deaths occurred, 627 due to CVD. In a subsample of 18,095 participants, 1,049 cases of nonfatal CVD events were ascertained. After adjustment for potential confounders, both measured and estimated CRF were inversely associated with risks for all-cause mortality, CVD-related mortality and nonfatal CVD events in men, and all-cause mortality and nonfatal CVD events in women. The risk reduction per 1-metabolic equivalent increase ranged from approximately 10% to 20%. Measured CRF had a slightly better discriminative ability (c statistic) than did estimated CRF, and the net reclassification improvement values in measured CRF versus estimated CRF were 12.3% in men (p < 0.05) and 19.8% in women (p < 0.001). Conclusions These CRF algorithms utilized information routinely collected to obtain an estimate of CRF, which provides a valid indication of health status. In addition to identifying people at risk, this method can provide more appropriate exercise recommendations that reflect initial CRF levels

Developing a framework for the analysis of power through depotentia

Stakeholder participation in tourism policy-making is usually perceived as providing a means of empowerment. However participatory processes drawing upon stakeholders from traditionally empowered backgrounds may provide the means of removing empowerment from stakeholders. Such an outcome would be in contradiction to the claims that participatory processes improve both inclusivity and sustainability. In order to form an understanding of the sources through which empowerment may be removed, an analytical perspective has been developed deriving from Lukes�s views of power dating from 1974. This perspective considers the concept of depotentia as the removal of �power to� without speculating upon the underlying intent and also provides for the multidimensionality of power to be examined within a single study. The application of this analytical perspective has been tested upon findings of the government-commissioned report of the Countryside and Community Research Unit in 2005. The survey and report investigated the progress of Local Access Forums in England created in response to the Countryside and Rights of Way Act 2000. Consideration of the data from this perspective permits the classification of individual sources of depotentia which can each be addressed and potentially enable stakeholder groups to reverse loss of empowerment where it has occurred

Dose-response effects of exercise training on the subjective sleep quality of postmenopausal women: exploratory analyses of a randomised controlled trial

Objective: To investigate whether a dose-response relationship existed between exercise and subjective sleep quality in postmenopausal women. This objective represents a post hoc assessment that was not previously considered. Design: Parallel-group randomised controlled trial. Setting: Clinical exercise physiology laboratory in Dallas, Texas. Participants: 437 sedentary or overweight/obese postmenopausal women. Intervention: Participants were randomised to one of four treatments, each of 6 months of duration: a non-exercise control treatment (n=92) or one of three dosages of moderate-intensity exercise (50% of VO2peak), designed to meet 50% (n=151), 100% (n=99) or 150% (n=95) of the National Institutes of Health Consensus Development Panel physical activity recommendations. Exercise dosages were structured to elicit energy expenditures of 4, 8 or 12 kilocalories per kilogram of body weight per week (KKW), respectively. Analyses were intent to treat. Primary outcome measures: Continuous scores and odds of having significant sleep disturbance, as assessed by the Sleep Problems Index from the 6-item Medical Outcomes Study Sleep Scale. Outcome assessors were blinded to participate radomisation assignment. Results: Change in the Medical Outcomes Study Sleep Problems Index score at 6 months significantly differed by treatment group (control: -2.09 (95% CI -4.58 to 0.40), 4 KKW: -3.93 (-5.87 to -1.99), 8 KKW: -4.06 (-6.45 to -1.67), 12 KKW: -6.22 (-8.68 to -3.77); p=0.04), with a significant dose-response trend observed (p=0.02). Exercise training participants had lower odds of having significant sleep disturbance at postintervention compared with control (4 KKW: OR 0.37 (95% CI 0.19 to 0.73), 8 KKW: 0.36 (0.17 to 0.77), 12 KKW: 0.34 (0.16 to 0.72)). The magnitude of weight loss did not differ between treatment conditions. Improvements in sleep quality were not related to changes in body weight, resting parasympathetic control or cardiorespiratory fitness. Conclusion: Exercise training induced significant improvement in subjective sleep quality in postmenopausal women, with even a low dose of exercise resulting in greatly reduced odds of having significant sleep disturbance