Kelley Pettee Gabriel

Evaluation of Physical Activity Measures Used in Middle-aged Women

PURPOSEnTo evaluate the reliability and validity of five commonly used physical activity questionnaires (PAQ) in women aged 45-65 yr with varying physical activity (PA) levels.nnnMETHODSnData were obtained from the Evaluation of Physical Activity Measures in Middle-aged Women (PAW) Study and included 66 women (aged 52.6 +/- 5.4 yr). PAQ evaluated include Modifiable Activity Questionnaire (past week and past month version), Nurses Health Study PAQ, Active Australia Survey, and Womens Health Initiative PAQ. Intraclass correlation coefficients (ICC) between administrations of the PAQ were used to assess test-retest reliability. Spearman rank-order correlation coefficients were used to examine the associations of PA and physical fitness data with PAQ summary estimates.nnnRESULTSnAccelerometer-determined median (25th, 75th percentiles) times (min.d) spent in moderate-lifestyle [760-1951 counts (ct)], moderate-walk (1952-5724 ct), vigorous (> or =5725 ct), and combined moderate and vigorous PA (MVPA > or = 1952 ct) during the 35 d of observation were 66.0 (51.2, 81.3), 23.1 (14.1, 34.6), 0.4 (0.0, 2.3), and 24.3 (15.9, 41.6) min, respectively. The PAQ were shown to be reproducible and relatively stable over time (ICC = 0.32 to 0.91) and were associated with total counts per day (ct.d, 0.46 to 0.60, all P < 0.001), and most were associated with many facets of physical fitness, including cardiorespiratory fitness (0.36 to 0.46, P < 0.01), body composition (-0.27 to -0.34, P < 0.05), and muscular fatigue (-0.25 to -0.44, P < 0.05).nnnCONCLUSIONSnThe PAQ evaluated in this study were shown to be reliable and associated with PA and physical fitness measures. Current findings support the utility of these PAQ for PA assessment in research studies of middle-aged women.

Issues in accelerometer methodology: the role of epoch length on estimates of physical activity and relationships with health outcomes in overweight, post-menopausal women

BackgroundCurrent accelerometer technology allows for data collection using brief time sampling intervals (i.e., epochs). The study aims were to examine the role of epoch length on physical activity estimates and subsequent relationships with clinically-meaningful health outcomes in post-menopausal women.MethodsData was obtained from the Woman On the Move through Activity and Nutrition Study (n = 102). Differences in activity estimates presented as 60s and 10s epochs were evaluated using paired t-tests. Relationships with health outcomes were examined using correlational and regression analyses to evaluate differences by epoch length.ResultsInactivity, moderate- and vigorous-intensity activity (MVPA) were significantly higher and light-intensity activity was significantly lower (all P < 0.001) when presented as 10s epochs. The correlation between inactivity and self-reported physical activity was stronger with 10s estimates (P < 0.03); however, the regression slopes were not significantly different. Conversely, relationships between MVPA and body weight, BMI, whole body and trunk lean and fat mass, and femoral neck bone mineral density was stronger with 60s estimates (all P < 0.05); however, regression slopes were similar.ConclusionThese findings suggest that although the use of a shorter time sampling interval may suggestively reduce misclassification error of physical activity estimates, associations with health outcomes did not yield strikingly different results. Additional studies are needed to further our understanding of the ways in which epoch length contributes to the ascertainment of physical activity in research studies.Trial RegistrationClinical Trials Identifier: NCT00023543

Adolescent Diet and Subsequent Serum Hormones, Breast Density, and Bone Mineral Density in Young Women: Results of the Dietary Intervention Study in Children Follow-up Study

Background: Adolescent diet is hypothesized to influence breast cancer risk. We evaluated the long-term effects of an intervention to lower fat intake among adolescent girls on biomarkers that are related to breast cancer risk in adults. Methods: A follow-up study was conducted on 230 girls who participated in the Dietary Intervention Study in Children (DISC), in which healthy, prepubertal, 8 to 10 year olds were randomly assigned to usual care or to a behavioral intervention that promoted a reduced fat diet. Participants were 25 to 29 years old at follow-up visits. All tests of statistical significance are two-sided. Results: In analyses that did not take account of diet at the time of the follow-up visit, the only statistically significant treatment group difference was higher bone mineral content in intervention group participants compared with usual care group participants; their mean bone mineral contents were 2,444 and 2,377 g, respectively. After adjustment for current diet, the intervention group also had statistically significantly higher bone mineral density and luteal phase serum estradiol concentrations. Serum progesterone concentrations and breast density did not differ by treatment group in unadjusted or adjusted analyses. Conclusions: Results do not support the hypothesis that consumption of a lower fat diet during adolescence reduces breast cancer risk via effects on subsequent serum estradiol and progesterone levels, breast density, or bone mineral density. It remains unclear, however, if the results are specific to the DISC intervention or are more broadly applicable. Impact: Modest reductions in fat intake during adolescence are unlikely to lower later breast cancer risk via long-term effects on the biomarkers measured. Cancer Epidemiol Biomarkers Prev; 19(6); 1545–56. ©2010 AACR.

Building Healthy Lifestyles Conference: Modifying Lifestyles to Enhance Physical Activity and Diet and Reduce Cardiovascular Disease

CVD is the leading cause of mortality in the U.S. with multiple etiologies comprising several levels of influence. The 3rd annual Building Healthy Lifestyles conference program explored the historical evidence that advanced CVD to become the leading cause of death in the U.S. The conference also examined the current evidence regarding the impact of lifestyle behaviors that either prevent (i.e., healthy dietary practices and regular physical activity) or promote (i.e., stress and poor sleep habits) CVD. Finally, CVD has been shown to disproportionately affect ethnically diverse populations; therefore, the conference also focused on strategies that are used to reduce the burden of CVD.

Comprehensive evaluation of a single-stage submaximal treadmill walking protocol in healthy, middle-aged women

Cardiorespiratory fitness is an independent predictor of cardiovascular events in women; however, maximal oxygen consumption (VO2max) protocols are not always feasible. The Evaluation of Physical Activity Measures in Middle-Aged Women Study was a 6-week study designed to evaluate six physical activity (PA) measures in women, aged 45–65xa0years. We investigated the Ebbeling submaximal treadmill (EbbTM) protocol’s ability to reflect an active lifestyle in 66 women [median (IQR) age, 51.0 (48.0, 56.5) years]. Participants were screened using ACSM and AHA guidelines and classified as moderate or low cardiovascular risk. VO2max was estimated using the EbbTM in all participants (TEST1). Moderate risk women repeated the EbbTM (TEST2) while low risk completed a maximal treadmill test. Intraclass correlation coefficients (ICC) and minimal detectable change (MDC90) score were calculated to examine reliability. Spearman rank order or Pearson product-moment correlation coefficients were used to determine the association between estimated VO2max and physical fitness and activity measures. Estimated VO2max from the EbbTM protocol had excellent reproducibility [ICCxa0=xa00.95 (95% CI: 0.89, 0.98) and MDC90 was 1.62xa0mLxa0kg−1xa0min−1. The EbbTM protocol was associated with measured VO2max (ρxa0=xa00.48; pxa0=xa00.01) and was positively correlated with moderate- (ρxa0=xa00.32; pxa0=xa00.02), vigorous- (ρxa0=xa00.47; pxa0=xa00.0005) and moderate-to-vigorous-intensity PA (ρxa0=xa00.36; pxa0=xa00.009), pedometer steps (ρxa0=xa00.41; pxa0=xa00.002) and inversely correlated with waist circumference (ρxa0=xa0−0.58; pxa0<xa00.0001), body fat (ρxa0=xa0−0.55; pxa0<xa00.0001), and right leg endurance (ρxa0=xa0−0.41; pxa0=xa00.003). The EbbTM protocol was shown to be reliable and associated with objective measures of fitness and PA in healthy, middle-aged women.

Recent evidence exploring the associations between physical activity and menopausal symptoms in midlife women: perceived risks and possible health benefits

Although the health benefits of physical activity are well established, the prevalence of midlife women accumulating sufficient physical activity to meet current physical activity guidelines is strikingly low, as shown in United States (U.S.) based surveillance systems that utilize either (or both) participant-reported and device-based (i.e., accelerometers) measures of activity. For midlife women, these low prevalence estimates may be due, in part, to a general lack of time given more pressing work commitments and family obligations. Further, the benefits or “reward” of allocating limited time to physical activity may be perceived, by some, as too distant for immediate action or attention. However, shifting the health promotion message from the long term benefits of physical activity to the more short-term, acute benefits may encourage midlife women to engage in more regular physical activity. In this article, we review the latest evidence (i.e., past 5xa0years) regarding the impact of physical activity on menopausal symptoms. Recent studies provide strong support for the absence of an effect of physical activity on vasomotor symptoms; evidence is still inconclusive regarding the role of physical activity on urogenital symptoms (vaginal dryness, urinary incontinence) and sleep, but consistently suggestive of a positive impact on mood and weight control. To further advance this field, we also propose additional considerations and future research directions.

Accelerometer determined sedentary behavior and dietary quality among US adults

OBJECTIVEnScant evidence exists pertaining to objectively measured sedentary time and dietary quality among adults. Therefore, we examined the relationships between sedentary time, physical activity, and dietary quality.nnnMETHODSnCross-sectional analyses of a 4,910 US adults from two cycles (2003-2006) of the National Health and Nutrition Examination Survey. The primary independent variables were sedentary time and physical activity (continuous and categorical), while the outcomes were overall dietary quality (Healthy Eating Index (HEI) 2010), fruit and vegetable scores, and empty caloric intake (kcal).nnnRESULTSnMultivariable analyses revealed that a 1min increase in daily sedentary behavior was associated with a 0.2kcal decrease in empty calories (-0.18, 95% CI=-0.34, -0.03); however, sedentary time was not significantly related to overall dietary quality (HEI) and fruit and vegetable intake. In comparison, a 1min increase in daily moderate-to-vigorous intensity physical activity was related to a 0.1 higher HEI score (0.08, 95% CI=0.04, 0.11), a 0.01 higher fruit score (0.01, 95% CI=0.01, 0.02), and conversely a 1.3kcal decrease in empty calories (-1.35, 95% CI=-2.01, -0.69). In addition, meeting physical activity guidelines was associated with a 2.8 point higher HEI score (2.82, 95% CI=1.40, 4.25), a 0.5 point higher fruit score (0.51, 95% CI=0.31-0.71), and 37.4 fewer empty calories (-37.43, 95% CI=-64.86, -9.10).nnnCONCLUSIONSnPhysical activity is significantly related to better overall dietary quality, while sedentary behavior is not. Findings suggest the need to promote physical activity and encourage adherence to dietary guidelines jointly, whereas sedentary behavior and overall dietary quality might need to be targeted independently.

Bidirectional associations of accelerometer-determined sedentary behavior and physical activity with reported time in bed: Women's Health Study

Objective: To examine the day‐to‐day, bidirectional associations of accelerometer‐derived sedentary behavior and physical activity (PA) with reported time in bed in a large cohort of older women. Methods: Data are from 10 086 Womens Health Study participants (aged 71.6 years; SD, 5.7) who agreed to wear an accelerometer and complete a diary for 7 consecutive days. Generalized linear (multilevel) models with repeated measures were used to examine the adjusted associations of the following: (1) reported time in bed with next‐day accelerometer‐determined counts and time spent sedentary and in light‐ and moderate‐to‐vigorous–intensity PA (MVPA) and (2) accelerometer estimates with reported time in bed that night, expressed as short (<7 hours), optimal (7‐9 hours), and long (>9 hours) sleep. Results: Across days, short sleep was associated with an average of 5500 (SE, 1352) higher accelerometer counts the following day but was also related to higher average sedentary (46.5 [SE, 1.5] minutes) and light‐intensity PA (11.9 [SE, 1.2] minutes) than optimal sleep (all P < .001). Long sleep was associated with lower accelerometer counts, time spent sedentary and in light‐intensity PA, and a reduced likelihood of engaging in ≥20 minutes of MVPA (all P < .001) than optimal sleep. Higher PA during the day (higher accelerometer counts and ≥20 minutes of accumulated MVPA) was associated with a reduced likelihood of reporting short or long sleep that night (all P < .001). Conclusions: Findings support the bidirectional associations of accelerometer‐determined sedentary behavior and PA with reported time in bed in older women. Future studies are needed to confirm findings with sleep actigraphy in older women.

U.S. military service and the prevalence of metabolic syndrome: Findings from a cross-sectional analysis of the Cooper Center Longitudinal Study, 1979–2013

U.S. military service confers both health benefits and risks potentially associated with a clustering of cardiovascular risk factors called metabolic syndrome. However, the association between prior military service and metabolic syndrome has not sufficiently been examined. The purpose of the study was to compare the prevalence of metabolic syndrome by prior military service status. Among 42,370 men (887 with prior military service) examined from 1979 to 2013 at the Cooper Clinic (Dallas, TX), we used a cross-sectional study design to examine the association between military service and metabolic syndrome. First, an unadjusted log binomial regression model was performed by regressing the prevalence of metabolic syndrome on prior service. This was followed by performing Kleinbaums modeling strategy for assessing confounding. The same methodology was used to explore the association between individual metabolic syndrome risk factors and prior service. Prior military service was not significantly associated with the prevalence of metabolic syndrome (PR=0.98, 0.89-1.07). None of the variables explored were identified as confounders. Participants with prior military service had lower prevalence of both elevated levels of triglycerides (PR=0.89, 0.80-0.99) and low levels of high-density lipoprotein-cholesterol (PR=0.78, 0.70-0.88). They had a higher prevalence of elevated resting systolic blood pressure (PR=1.23, 1.12-1.35). However, none of these associations were significant after adjusting for identified confounders: age; cardiorespiratory fitness; and exam year. Study findings indicate that military service was not independently associated with the prevalence of metabolic syndrome or its components. Future research is warranted longitudinally assessing the impact of military service on long-term outcomes.

Youth and Young Adult Physical Activity and Body Composition of Young Adult Women: Findings from the Dietary Intervention Study in Children

This study prospectively investigates associations between youth moderate-to-vigorous-intensity physical activity (MVPA) and body composition in young adult women using data from the Dietary Intervention Study in Children (DISC) and the DISC06 Follow-Up Study. MVPA was assessed by questionnaire on 5 occasions between the ages 8 and 18 years and at age 25-29 years in 215 DISC female participants. Using whole body dual-energy x-ray absorptiometry (DXA), overall adiposity and body fat distribution were assessed at age 25-29 years by percent body fat (%fat) and android-to-gynoid (A:G) fat ratio, respectively. Linear mixed effects models and generalized linear latent and mixed models were used to assess associations of youth MVPA with both outcomes. Young adult MVPA, adjusted for other young adult characteristics, was significantly inversely associated with young adult %fat (%fat decreased from 37.4% in the lowest MVPA quartile to 32.8% in the highest (p-trend = 0.02)). Adjusted for youth and young adult characteristics including young adult MVPA, youth MVPA also was significantly inversely associated with young adult %fat (β=-0.40 per 10 MET-hrs/wk, p = .02) . No significant associations between MVPA and A:G fat ratio were observed. Results suggest that youth and young adult MVPA are important independent predictors of adiposity in young women.