William R. Boyer

Association between alcohol consumption patterns and metabolic syndrome

AIMS Examine associations between self-reported alcohol consumption patterns and metabolic syndrome. MATERIALS AND METHODS Sample (N=7432) included adult (≥20 years) participants in the 1999-2006 National Health and Nutrition Examination Survey. RESULTS Above moderate alcohol consumption (AMAC) was negatively associated with waist circumference among those in the 20-29, 40-49, and 70-79 age groups (β=-6.21, β=-8.34, and β=-6.60, respectively) and moderate alcohol consumption (MAC) was negatively associated with waist circumference among those in the 30-39, 40-49, and 70-79 age groups (β=-4.60, β=-5.69, and β=-2.88, respectively). AMAC was negatively associated with triglycerides among those in the 70-79 and 80+ age groups (β=-23.62 and β=-34.18, respectively) and positively associated with HDL-C levels in all groups (β range 8.96-18.25). MAC was positively associated with HDL-C in the age groups spanning 20-69 years (β range 3.05-5.34) and those over 80 (β=5.26). AMAC and MAC were negatively associated with fasting glucose levels in the 20-29 and 70-79 age groups (β=-3.38 and -15.61, respectively). MAC was negatively associated with fasting glucose levels among those 70-79 and those over 80 years of age (β=-7.06 and β=-5.00, respectively). CONCLUSION MAC and AMAC may favorably impact metabolic health.

Accuracy of Consumer Monitors for Estimating Energy Expenditure and Activity Type.

Introduction Increasing use of consumer-based physical activity (PA) monitors necessitates that they are validated against criterion measures. Thus, the purpose of this study was to examine the accuracy of three consumer-based PA monitors for estimating energy expenditure (EE) and PA type during simulated free-living activities. Methods Twenty-eight participants (mean ± SD: age, 25.5 ± 3.7 yr; body mass index, 24.9 ± 2.6 kg·m−2) completed 11 activities ranging from sedentary behaviors to vigorous intensities. Simultaneous measurements were made with an Oxycon portable calorimeter (criterion), a Basis Peak and Garmin Vivofit on the nondominant wrist, and three Withings Pulse devices (right hip, shirt collar, dominant wrist). Repeated-measures ANOVA were used to examine differences between measured and predicted EE. Intraclass correlation coefficients were calculated to determine reliability of EE predictions between Withings placements. Paired samples t tests were used to determine mean differences between observed minutes and Basis Peak predictions during walking, running, and cycling. Results On average, the Basis Peak was within 8% of measured EE for the entire PA routine (P > 0.05); however, there were large individual errors (95% prediction interval, −290.4 to +233.1 kcal). All other devices were significantly different from measured EE for the entire PA routine (P < 0.05). For activity types, Basis Peak correctly identified ≥92% of actual minutes spent walking and running (P > 0.05), and 40.4% and 0% of overground and stationary cycling minutes, respectively (P < 0.001). Conclusions The Basis Peak was the only device that did not significantly differ from measured EE; however, it also had the largest individual errors. Additionally, the Basis Peak accurately predicted minutes spent walking and running, but not cycling.

The associations between increasing degrees of homeostatic model assessment for insulin resistance and muscular strengthening activities among euglycaemic US adults

Purpose: To examine the associations between the homeostatic model assessment for insulin resistance and self-reported muscular strengthening activity in a nationally representative sample of euglycaemic US adults. Methods: Sample included euglycaemic adults (⩾20 years of age (n = 2009)) from the 1999 to 2004 National Health and Nutrition Examination Survey. Homeostatic model assessment for insulin resistance was categorized into quartiles and was the primary independent variable of interest. No reported muscular strengthening activity was the dependent variable. Results: Following adjustment for covariates, those with homeostatic model assessment for insulin resistance values in fourth (odds ratio: 2.04, 95% confidence interval: 1.35−3.06, p < 0.001) quartile were found to have significantly greater odds of reporting no muscular strengthening activity. Following further adjustment for non-muscular strengthening activity specific aerobic leisure-time physical activity, results remained significant for the fourth (odds ratio: 2.30, 95% confidence interval: 1.50−3.52, p < 0.001) quartile. A significant trend was seen across quartiles of homeostatic model assessment for insulin resistance for increasing prevalence of no muscular strengthening activity (p < 0.001). Conclusion: Having a higher homeostatic model assessment for insulin resistance value is associated with greater odds of reporting no muscular strengthening activity among euglycaemic US adults. This implies that subjects with an increasing degree of insulin resistance are more likely to not engage in muscular strengthening activity, an exercise modality that has been shown to reduce the risk of several cardiometabolic diseases and improve glycaemic status.

Use of population-referenced total activity counts percentiles to assess and classify physical activity of population groups

OBJECTIVES Population-referenced total activity counts per day (TAC/d) percentiles provide public health practitioners a standardized measure of physical activity (PA) volume obtained from an accelerometer that can be compared across populations. The purpose of this study was to describe the application of TAC/d population-referenced percentiles to characterize the PA levels of population groups relative to US estimates. METHODS A total of 679 adults participating in the 2011 NYC Physical Activity Transit survey wore an ActiGraph accelerometer on their hip for seven consecutive days. Accelerometer-derived TAC/d was classified into age- and gender-specific quartiles of US population-referenced TAC/d to compare differences in the distributions by borough (N=5). RESULTS Males in Brooklyn, Manhattan, and Staten Island had significantly greater TAC/d than US males. Females in Brooklyn and Queens had significantly greater levels of TAC/d compared to US females. The proportion of males in each population-referenced TAC/d quartile varied significantly by borough (χ(2)(12)=2.63, p=0.002), with disproportionately more men in Manhattan and the Bronx found to be in the highest and lowest US population-referenced TAC/d quartiles, respectively. For females, there was no significant difference in US population-reference TAC/d quartile by borough (χ(2)(12)=1.09, p=0.36). CONCLUSIONS These results demonstrate the utility of population-referenced TAC/d percentiles in public health monitoring and surveillance. These findings also provide insights into the PA levels of NYC residents relative to the broader US population, which can be used to guide health promotion efforts.

Associations between mental distress and physical activity in US adults: a dose–response analysis BRFSS 2011

Background To examine the associations between levels of severity of mental distress (MD) and meeting the 2008 physical activity (PA) recommendations using the MD Severity Index (MDSI). Methods Participants (n = 431 313) were adults (≥18 years of age) who responded to the 2011 Behavioral Risk Factor Surveillance System (BRFSS). MD was categorized into five levels of severity: 0-4, 5-10, 11-16, 17-22 and ≥23 days/month. The dependent variable was self-reported PA volume of at least 150 min/wk (or vigorous equivalent, 75 min/wk). Results Following adjustment for age, gender, race/ethnicity, education and body mass index, the odds of reporting meeting the PA recommendations were significantly lower among those reporting the following days per month of MD: 5-10 (odds ratio [OR] = 0.92, 95% confidence interval [CI]: 0.87-0.96), 11-16 (OR = 0.76, 95% CI: 0.71-0.82), 17-22 (OR = 0.69, 95% CI: 0.62-0.76) and ≥23 (OR = 0.64, 95% CI: 0.60-0.67). An inverse dose-response (P < 0.01) was observed between the severity of MD and meeting the current PA recommendations. Conclusions An inverse dose-response relationship was found between the severity of MD and volumes of PA meeting the 2008 recommendation. These findings lend support for the epidemiological utility of the MDSI when examining the relationship between MD and PA.

Gender Differences in C-Reactive Protein and Muscle Strengthening Activity.

BACKGROUND Few studies have examined the gender differences between C-reactive protein (CRP) and muscle strengthening activity (MSA). METHODS The sample (n = 7533) included U.S. adult (≥20 years of age).participants in the 1999-2004 National Health and Nutrition Examination Survey (NHANES). Created categories of MSA participation included no MSA (referent group), some MSA (≥1 to <2 days/week), and meeting the 2008 Department of Health and Human Services (DHHS) recommendation (≥2 days/week). The dependent variable was elevated CRP (>3 to 10 mg/L). RESULTS Analysis revealed significantly lower odds of having elevated CRP for women reporting some MSA (OR 0.64; 95% CI 0.44-0.93, P = .0191). Significantly lower odds of men having elevated CRP was observed in those reporting MSA volumes meeting the DHHS recommendation (OR 0.72; 95% CI 0.59-0.88, P = .0019). Following adjustment for waist circumference (WC) these odds remained significant in men but not women. CONCLUSIONS These results suggest that WC may mediate the associations between MSA and CRP and this relationship may be stronger in women.

The Protective Role of Physical Activity on Type 2 diabetes: An Analysis of Effect Modification by Race-Ethnicity

It is well known physical activity (PA) plays a role in the prevention of type 2 diabetes (T2D). However, the extent to which PA may affect T2D risk among different race–ethnic groups is unknown. Therefore, the aim of the present study was to systematically examine the effect modification of race–ethnicity on PA and T2D.