Background: Accelerometers were incorporated in the 2003-2004 National Health and Nutritional Examination Survey (NHANES) study cycle for objective assessment of physical activity. This is the first time that objective physical activity data are available on a nationally representative sample of U.S. residents. The use of accelerometers allows researchers to measure total physical activity, including light intensity and unstructured activities, which may be a better predictor of health outcomes than structured activity alone. The aim of this study was to examine objectively determined physical activity levels by sex, age and racial/ethnic groups in a national sample of U.S. adults.

AIMS: To pilot the feasibility of a prenatal lifestyle intervention to modify physical activity and diet among pregnant overweight and obese Hispanic women, with the aim of reducing risk factors for gestational diabetes mellitus. METHODS: Women were randomized either to a lifestyle intervention (n = 33, 48.5%), consisting of a culturally and linguistically modified, motivationally targeted, individually tailored 6-month prenatal programme, or to standard care (n = 35, 51.5%). Bilingual and bicultural health educators encouraged women to achieve guidelines for physical activity, decrease saturated fat and increase dietary fibre. Outcomes included gestational weight gain, infant birth weightand biomarkers associated with insulin resistance. RESULTS: Patient retention up to delivery was 97% in both study groups. The lifestyle intervention attenuated the pregnancy-associated decline in moderate-intensity physical activity, but differences between groups were not significant (mean +/- se -23.4 +/- 16.6 vs -27.0 +/- 16.2 metabolic equivalent of task h/week; P = 0.88). Vigorous-intensity activity increased during the course of pregnancy in the lifestyle intervention group (mean +/- se 1.6 +/- 0.8 metabolic equivalent of task h/week) and declined in the standard care group (-0.8 +/- 0.8 metabolic equivalent of task h/week; P = 0.04). The lifestyle intervention group also had slightly lower gestational weight gain and infant birth weights compared with the standard care group; however, these differences were not statistically significant. There were no statistically significant differences in biomarkers of insulin resistance between groups. CONCLUSIONS: Findings suggest that a motivationally matched lifestyle intervention is feasible and may help attenuate pregnancy-related decreases in vigorous physical activity in a population of overweight and obese Hispanic women. The intervention protocol can readily be translated into clinical practice in underserved and minority populations

SummaryBackground and objective The association of large arterial rigidity and kidney function decline in longitudinal analyses is not well established. This study evaluated the association of aortic pulse wave velocity (aPWV) and pulse pressure (PP) with rapid kidney function decline and incident CKD in the Health, Aging and Body Composition study.Design, setting, participants, & measurements Participants were 2129 older adults with a baseline measurement of aPWV, PP, and cystatin C and at least one additional measurement of cystatin C, either at year 3 or year 10. Outcomes were rapid kidney function decline (estimated GFR cysC loss of .3 ml/min per 1.73 m 2 per year) and incident CKD (eGFR cysC , 60 ml/min per 1.73 m 2 in participants with baseline estimated GFR . 60 ml/min per 1.73 m 2 ). Multivariate regression models were used to evaluate association of aPWV and PP with each outcome.Results Mean (SD) baseline estimated GFR cysC was 79629 ml/min per 1.73 m 2 . Median follow-up duration was 8.9 years. In multivariable analyses, aPWV was not associated with rapid decline (odds ratio [OR], 95% confidence interval [CI] 1.16, 0.89-1.52) but was associated with incident CKD (incident rate ratio [IRR], 95% CI, 1.39, 1.09-1.77) and PP was associated with both rapid decline (OR, 95% CI 1.10, 1.04-1.16) and incident CKD (IRR, 95% CI, 1.06, 1.01-1.11).Conclusions Large arterial stiffness assessed by aPWV and pulsatility assessed by PP were associated with incident CKD among older adults. Pulsatility assessed by PP was associated with rapid kidney function decline and incident CKD. Future research should determine whether interventions targeting arterial rigidity will prevent CKD development and progression.

When examining the association between physical activity, measured objectively with an accelerometer, and kidney function, total and light physical activities were found to be positively associated with kidney function.

BackgroundChronic arterial stiffness contributes to the negative health effects of obesity and insulin resistance, which include hypertension, stroke, and increased cardiovascular and all-cause mortality. Weight loss and improved insulin sensitivity are individually associated with improved central arterial stiffness; however, their combined effects on arterial stiffness are poorly understood. The purpose of this study was to determine how insulin levels modify the improvements in arterial stiffness seen with weight loss in overweight and obese young adults.MethodsTo assess the effects of weight loss and decreased fasting insulin on vascular stiffness, we studied 339 participants in the Slow the Adverse Effects of Vascular Aging (SAVE) trial. At study entry, the participants were aged 20–45, normotensive, non-diabetic, and had a body-mass index of 25–39.9 kg/m2. Measures of pulse wave velocity (PWV) in the central (carotid-femoral (cfPWV)), peripheral (femoral-ankle (faPWV)), and mixed (brachial-ankle (baPWV)) vascular beds were collected at baseline and 6 months. The effects of 6-month change in weight and insulin on measures of PWV were estimated using multivariate regression.ResultsAfter adjustment for baseline risk factors and change in systolic blood pressure, 6-month weight loss and 6-month change in fasting insulin independently predicted improvement in baPWV but not faPWV or cfPWV. There was a significant interaction between 6-month weight change and change in fasting insulin when predicting changes in baPWV (p < 0.001). Individuals experiencing both weight loss and insulin reductions showed the greatest improvement in baPWV.ConclusionsYoung adults with excess weight who both lower their insulin levels and lose weight see the greatest improvement in vascular stiffness. This improvement in vascular stiffness with weight loss and insulin declines may occur throughout the vasculature and may not be limited to individual vascular beds.Trial registrationNCT00366990

BACKGROUND Physical activity (PA) may play a role in preserving kidney health. The purpose of this study was to determine if PA and sedentary behavior are associated with incident chronic kidney disease (CKD) and change in kidney function in older adults. METHODS The Health, Aging and Body Composition study is a prospective cohort of 3,075 well-functioning older adults. PA and television watching was measured by self-report and serum cystatin C was used to estimate glomerular filtration rate (eGFR). CKD was defined as an eGFR <60 ml/min/1.73m2. Rapid kidney function decline was defined as an annual loss in eGFR of >3ml/min/1.73m2. Discrete survival analysis was used to determine if baseline PA and television watching were related to 10-year cumulative incidence of CKD and rapid decline in kidney function. RESULTS Individuals who reported watching television >3 hours/day had a higher risk of incident CKD (HR 1.34; 95% CI: 1.09, 1.65) and experiencing a rapid decline in kidney function (HR 1.26; 95% CI 1.05, 1.52) compared to individuals who watched television < 2 hours/day. PA was not related to either outcome. CONCLUSIONS High levels of television watching are associated with declining kidney function; the mechanisms that underlie this association need further study.

Objectively measured light-intensity physical activity had a protective effect on CRP among women in the second trimester of pregnancy. Findings highlight the need for longitudinal studies of pregnancy physical activity and CRP with careful control for clinical characteristics of the current pregnancy.

Objectives. We examined the impact of a prenatal exercise intervention on physical activity in 260 women at risk for gestational diabetes mellitus. Methods. We randomized participants in the Behaviors Affecting Baby and You (BABY) Study, which took place from 2007 to 2012, to either a 12-week individually tailored, motivationally matched exercise intervention (n = 132) or to a comparison health and wellness intervention (n = 128). We assessed physical activity with the Pregnancy Physical Activity Questionnaire. We used linear mixed models to evaluate the impact of the interventions on change in physical activity according to intensity and type, total walking, and sedentary behavior. Results. Compared with the health and wellness arm, the exercise arm had significantly greater increases in sports or exercise activity (0.3 vs 5.3 metabolic equivalent of task [MET] hours/week; P < .001), and smaller declines in total activity (–42.7 vs –2.1 MET hours/week; P = .02) and activities of moderate to vigorous intensity (–30.6 vs −10.6 MET hours/week; P = .05), and was more likely to achieve recommended guidelines for physical activity (odds ratio = 2.12; 95% confidence interval = 1.45, 3.10). Conclusions. These findings extend the previous literature by demonstrating the benefits of a clinically feasible exercise intervention in an ethnically and socio-economically diverse population. Given the increased risk of adverse maternal health outcomes in ethnic minority groups, these findings may have important implications for reducing health disparities.