Traditional physical activity indexes derived from the Harvard alumni activity survey have low construct validity in a lower income, urban population.
ABSTRACT The purpose of this study is to investigate the construct validity of the Harvard Alumni Activity Survey (HAAS) in an urban, lower income population. Data were collected from 192 smokers enrolled in an antioxidant micronutrient trial. Activity data were compared to body mass index (BMI), diastolic, and systolic blood pressure. The traditional physical activity index (PAI), using data on stair climbing, walking, and sports, was calculated including and excluding body mass. A new scale, the total weekly activity (TWA) scale, was derived from other questions on the HAAS. The PAI scale calculated with body mass was unassociated with BMI and blood pressure. The PAI scale calculated without body mass was unassociated with BMI and systolic blood pressure but was associated with diastolic blood pressure (Beta = -0.001, p = 0.03). The TWA scale was associated with BMI (Beta = -0.01, p = 0.01), diastolic (Beta = -0.03, p = 0.01), and systolic blood pressure (Beta = -0.04, p = 0.01). A one standard deviation change in the TWA scale is predicted to be equivalent to a change of 0.99 BMI units, 2.97 mmHg of diastolic blood pressure, and 3.96 mmHg of systolic blood pressure. This work suggests that the TWA scale has greater construct validity than the traditional PAI scale in this population.
Full-textDOI: · Available from: Laverne A Mooney, Jan 29, 2015
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ABSTRACT: Age-related declines in physical activity are commonly observed in human and animal populations, but their physiologic bases are not fully understood. The authors hypothesize that a lack of available energy contributes to low levels of activity in older persons. Cross-sectional analyses of relationships between physical activity level and energy availability were performed in 602 community-dwelling volunteers aged 45-91 yrs from the Baltimore Longitudinal Study of Aging. Energy expenditure was measured at rest and during a maximal 400-m walk for calculation of "available energy." Overall and vigorous physical activity levels were assessed using standardized questionnaires. General linear regression models were used to assess the relationships between available energy and general and vigorous physical activity, and stratified analyses were used to analyze the possible differential association between available energy and physical activity across high and low (peak sustained walking oxygen consumption per unit time, <18.3 ml of oxygen per kilogram per minute) levels of aerobic fitness. Low available energy was associated with low levels of total physical activity (β = 64.678, P = 0.015) and vigorous activity (β = 9.123, P < 0.0001). The direct relationship between available energy and physical activity was particularly strong in persons categorized as having low aerobic fitness between available energy and physical activity with both total (β = 119.783, P = 0.022) and vigorous activity (β = 10.246, P = 0.015) and was independent of body composition and age. The findings from this study support the hypothesis that available energy promotes the maintenance of physical activity in older persons. The findings also run counter to the perception that age-related declines in physical activity are primarily societally or behaviorally driven.American journal of physical medicine & rehabilitation / Association of Academic Physiatrists 05/2014; 93(10). DOI:10.1097/PHM.0000000000000108 · 2.01 Impact Factor
Journal of Leisure Research 01/2014; 46(5):540-562. · 0.51 Impact Factor
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ABSTRACT: To examine whether agreement between self-reported and accelerometer-measured physical activity varies by BMI category in a low-income black sample. Participants completed a questionnaire and wore an accelerometer for 4-6 days. Using one- and 10-minute bouts, accelerometers measured light, moderate, and vigorous physical activity time. Correlations varied by obesity (nonobese: one-minute r=0.41; 10-minute r=0.47; obese: one-minute r=0.21; 10-minute r=0 .14). Agreement was highest among nonobese persons (one-minute kappa = 0.48, 10-minute kappa = 0.023; obese: one-minute kappa = -0.024, 10- minute kappa = -0.020). We found compromised questionnaire performance among obese participants.American journal of health behavior 03/2012; 36(2):168-78. DOI:10.5993/AJHB.36.2.3 · 1.31 Impact Factor