Richard A. Washburn

The Physical Activity Scale for the Elderly (PASE): development and evaluation.

A Physical Activity Scale for the Elderly (PASE) was evaluated in a sample of community-dwelling, older adults. Respondents were randomly assigned to complete the PASE by mail or telephone before or after a home visit assessment. Item weights for the PASE were derived by regressing a physical activity principal component score on responses to the PASE. The component score was based on 3-day motion sensor counts, a 3-day physical activity dairy and a global activity self-assessment. Test-retest reliability, assessed over a 3-7 week interval, was 0.75 (95% CI = 0.69-0.80). Reliability for mail administration (r = 0.84) was higher than for telephone administration (r = 0.68). Construct validity was established by correlating PASE scores with health status and physiologic measures. As hypothesized, PASE scores were positively associated with grip strength (r = 0.37), static balance (r = +0.33), leg strength (r = 0.25) and negatively correlated with resting heart rate (r = -0.13), age (r = -0.34) and perceived health status (r = -0.34); and overall Sickness Impact Profile score (r = -0.42). The PASE is a brief, easily scored, reliable and valid instrument for the assessment of physical activity in epidemiologic studies of older people.

The Physical Activity Scale for the Elderly (PASE): Evidence for Validity

We assessed the validity of the Physical Activity Scale for the Elderly (PASE) in a sample of sedentary adults (56 men, 134 women, mean age +/- [SD] 66.5+/-5.3 years) who volunteered to participate in a randomized controlled trial on the effect of aerobic conditioning on psychological function. Construct validity was established by correlating PASE scores with physiologic and performance characteristics: peak oxygen uptake, resting heart rate and blood pressure, percent body fat, and balance. The mean PASE scores were higher in men than in women (men = 145.8+/-78.0; women = 123.9+/-66.3, P<0.05), and in those age 55-64 years compared with those age 65 years and over (55-64 = 144.2+/-75.8; 65 and over = 118.9+/-63.9, P<0.05). PASE scores were also significantly higher in those who did not report a chronic health condition (cardiovascular disease, hypertension, cancer, or recent surgery). PASE scores were significantly associated (P<0.05) with peak oxygen uptake (r = 0.20), systolic blood pressure (r = -0.18) and balance score (r = 0.20). No significant associations of PASE score and diastolic blood pressure, resting heart rate, or percent body fat were noted. These results provide additional evidence for the validity of the PASE as a measure of physical activity suitable for use in epidemiology studies on the association of physical activity, health, and physical function in older individuals.

Physical Activity Across the Curriculum (PAAC): a randomized controlled trial to promote physical activity and diminish overweight and obesity in elementary school children

BACKGROUND Physical Activity Across the Curriculum (PAAC) was a three-year cluster randomized controlled trial to promote physical activity and diminish increases in overweight and obesity in elementary school children. METHODS Twenty-four elementary schools were cluster randomized to the Physical Activity Across the Curriculum intervention or served as control. All children in grades two and three were followed to grades four and five. Physical Activity Across the Curriculum promoted 90 min/wk of moderate to vigorous intensity physically active academic lessons delivered by classroom teachers. Body Mass Index was the primary outcome, daily Physical activity and academic achievement were secondary outcomes. RESULTS The three-year change in Body Mass Index for Physical Activity Across the Curriculum was 2.0+/-1.9 and control 1.9+/-1.9, respectively (NS). However, change in Body Mass Index from baseline to 3 years was significantly influenced by exposure to Physical Activity Across the Curriculum. Schools with > or =75 min of Physical Activity Across the Curriculum/wk showed significantly less increase in Body Mass Index at 3 years compared to schools that had <75 min of Physical Activity Across the Curriculum (1.8+/-1.8 vs. 2.4+/-2.0, p=0.02). Physical Activity Across the Curriculum schools had significantly greater changes in daily Physical activity and academic achievement scores. CONCLUSIONS The Physical Activity Across the Curriculum approach may promote daily Physical activity and academic achievement in elementary school children. Additionally, 75 min of Physical Activity Across the Curriculum activities may attenuate increases in Body Mass Index.

Estimation of energy expenditure by a portable accelerometer

A small portable accelerometer was developed to estimate the energy expenditure of daily activities. The accelerometer is reported to be an improvement over movement counters currently on the market. The oxygen requirement of 14 different activities was measured in 21 subjects while each wore the accelerometer on the waist. A movement counter (mercury switch), which is available commercially, was also worn on the waist and another was worn on the left wrist. The reproducibility of the accelerometer readings was high (4 subjects, 14 activities; r = 0.94) and was superior to either the waist movement counter (r = 0.63) or the wrist movement counter (r = 0.74). In estimating oxygen requirement (VO2) the standard error of estimate, based on 21 subjects and 14 activities, was 6.6 ml X min-1 X kg-1 for the accelerometer. This was also better (smaller) than for the waist movement counter (9.2 ml X min-1 X kg-1) or for the wrist movement counter (7.9 ml X min-1 X kg-1).

Measurement of Physical Activity

This paper describes the problem of measuring physical activity in free-living populations, a premier challenge facing investigators trying to understand exercise adherence and its impact on public health. Valid methods of assessing physical activity are required that are unobtrusive, practical to administer, and specific about the type, frequency, duration, and intensity of physical activity, Existing methods can be categorized according to whether they measure a direct or indirect (e.g., self-report) observation of physical activity, energy expenditure, a physiological response during physical activity. a physiological adaptation to physical activity, or motion. On balance, self-reponof physical activity offers the most practical and cost-effective method for use in population based studies. Several objective methods such as direct observation. doubly labeled water. heart rate monitors, accelerometers, and change in fitness provide standards of comparison for the validation of self-reports. No single “gold standard” exists for judging the validity of physical activity measures. Hence, the methods chosen to assess physical activity may vary according to the nature of the research question being addressed.

Assessment of Physical Activity in Older Adults

D uring the past 10 to 15 years the association of physical activity, a modifiable behavioral factor, and the risk for chronic disease and functional decline in older individuals has received increased research attention (Heckler, 1985). Over ten years ago, data from the Alameda County Study showed that, among the elderly, participation in leisure time physical activity was associated with a decreased risk of mortality over a 17-year follow-up, that was independent of age, socioeconomic status, health status, smoking, relative weight and alcohol consumption (Kaplan, Seeman, Cohen, Knudsen & Guralnik, 1987). More recently, physical activity has been associated with a decreased risk for cardiovascular mortality in elderly Spanish men and women (Ruigomez, Alonso & An to, 1995), both cardiovascular and all-cause mortality in elderly Dutch men (Bijnen, Caspersen, et al., 1998), and with the incidence of coronary heart disease in middle-aged and elderlyJapanese American men living in Hawaii (Donahue, Abbott, Reed, & Yano, 1988). In addition, reports from the Established Populations for Epidemiologic Studies of the Elderly cohort have shown increased physical activity was significantly associated with a longer life expectancy at age 65 in both men and women, smokers and non-smokers (Ferrucci et aI., 1999), with fewer years of disability prior to death (Leveille, Guralnik, Ferrucci, & Langlois, 1999), and with a decreased risk of losing mobility (LaCroix, Guralnik, Berkman, Wallace, & Satterfield, 1993). Maintaining a

The validity of the Stanford Seven-Day Physical Activity Recall in young adults.

PURPOSE To evaluate the criterion validity of the 7-Day Physical Activity Recall (7D-PAR) and factors associated with reporting error, in a sample of moderately overweight, young adult men and women. METHODS Average total daily energy expenditure (TDEE) and physical activity energy expenditure (PAEE) from the 7D-PAR were compared with the same parameters assessed by doubly labeled water in 17 men, age = 23.9 +/- 3.8 yr, and 29 women, age = 23.3 +/- 4.6 yr, who volunteered to participate in a 16-month supervised aerobic exercise trial. PAEE was estimated from the 7D-PAR and from DLW [0.9 * TDEE -resting metabolic rate (RMR) (indirect calorimetry)]. In addition, peak oxygen uptake and percent body fat were obtained. RESULTS No significant differences in TDEE (kJ.d-1) were noted between the 7D-PAR (11825 +/- 1779) and DLW (11922 +/- 2516) for the complete sample (N = 46) or for men (7D-PAR = 13198 +/- 1638, DLW = 13885 +/- 2754) or women (7D-PAR = 11018 +/- 1323, DLW = 10771 +/- 1457. The mean PAEE from the 7D-PAR was not different from DLW in the total sample (7D-PAR = 3286 +/- 502, DLW = 3508 +/- 1863) as well as in men (7D-PAR = 3650 +/- 490, DLW = 3989 +/- 2461) and women (3073 +/- 377, DLW = 3223 +/- 1360). In a regression model, PAEE, peak oxygen uptake, gender and percent fat accounted for 86% of the reporting error in total daily energy expenditure when using the 7D-PAR. CONCLUSION The 7D-PAR provided a reasonable estimate of both the mean TDEE and PAEE in this sample; however, estimates of energy expenditure on an individual basis using the PAR were subject to considerable error.

Reliability and physiologic correlates of the Harvard alumni activity survey in a general population

The reliability of the Harvard Alumni Activity Survey (HAAS) and its association with physiologic measures was assessed in a large sample of men and women aged 25-65 years residing in the Boston metropolitan area in 1987. Reliability was estimated by comparing HAAS energy expenditure reports (kcal/week) from two separate interviews conducted 7-12 weeks apart. The test-retest reliability coefficient was 0.58 for the entire sample, but was considerably higher (r = 0.69) for those whose activity patterns had not changed from one interview to the next. HAAS self-reports were compared to two physiologic measures known to be affected by physical activity: high density lipoprotein cholesterol (HDLC) and body mass index (BMI). The natural logarithm of weekly HAAS expenditures was positively correlated with HDLC (r = 0.14, p less than 0.01) and negatively correlated with BMI (r = 0.13, p less than 0.01) for all respondents. These statistically significant associations persisted when adjusted for other covariates influencing physiologic status. The reliability coefficients and physiologic correlations for the HAAS in this sample are comparable to those reported for physical activity instruments requiring more intensive data collection and scoring procedures.

Reliability and Validity Issues concerning Large-Scale Surveillance of Physical Activity

The BRFSS is our major source of population-based information on physical activity in the United States. The top priority for the immediate future should be to make sure that the information obtained from the BRFSS in its current form is both reliable and valid. As outlined in this report, this task could be completed in relatively short time frame and at reasonable cost in terms of both financial and human resources. The development of an additional module to assess light-to-moderate activity and strength is currently underway with support from the CDC. As suggested in this report, this task may prove to be extremely difficult, or it may be difficult to develop an instrument of this type given the constraints of a population based telephone survey. The current focus on the health benefits of moderate activity and the interest in tracking this type of activity behavior on a population basis as it relates to national physical activity objectives both argue in favor of developing a physical activity assessment instrument that provides a valid and reliable measurement of moderate activity. Given the complexity and uncertainty of this task it is important to develop a procedure that will allow for periodic evaluation of progress and the potential for success to minimize the risk of making a considerable financial investment in an instrument that may be of limited utility.

Leisure time physical activity: are there black/white differences?

BACKGROUND Behavioral risk factor surveillance survey data collected during 1984 and 1985 in South Carolina were analyzed. METHODS This article is based on telephone interviews conducted with 2,005 individuals (431 black, 1574 white), mean age, 45.1 years, selected by random-digit dialing. Information on the type, frequency, and duration of leisure time physical activity was used to estimate leisure time energy expenditure (kcal/week) averaged over the previous month. The median level of leisure time energy expenditure differed significantly (all P less than 0.001) by gender (men = 741, women = 421), age (six categories; youngest, 18-29 years = 780; oldest, 70+ = 301), annual household income (four categories; lowest, less than or equal to