Rick Petosa

Validation of an instrument for measurement of physical activity in youth

This study assessed the reliability and validity of the Previous Day Physical Activity Recall (PDPAR), a self-report instrument designed to measure physical activity in youth. Subjects were randomly selected students in grades 7-12. Test-retest reliability was reported as the correlation between estimated relative energy expenditures determined from two PDPAR administrations completed within 1 h. Interrater reliability was determined by two observers using the scoring protocol. Validity was assessed using footstrikes (pedometer), Caltrac activity counts, and heart rate monitoring as criterion measures. Interrater and test-retest reliability was 0.99 and 0.98, respectively (P < 0.01). The correlation between relative energy expenditure from the PDPAR (kcal.kg-1.l.d-1) and pedometer and Caltrac counts was 0.88 (P < 0.01) and 0.77 (P < 0.01), respectively. The correlation between percentage heart rate range (HRmax-HR-rest) and mean energy expenditure from the PDPAR was 0.53 (P < 0.01). The correlation between 1-min heart rates > 50% HRR sustained for 20 min and the number of 30-min blocks with a relative energy expenditure of at least four metabolic equivalent tasks (MET) was 0.63 (P < 0.01). The PDPAR provides valid and reliable estimates of physical activity and also accurately identifies bouts of moderate to vigorous activity.

Physical activity among ethnically diverse college students

Abstract The authors compared physical activity patterns among 874 Asian, 332 African, 1,101 White, and 529 Hispanic American college students aged 18 to 25 years. According to self-report responses, 46.7% of the sample did not engage in vigorous physical activity and 16.7% were physically inactive. Among women, ethnic-specific rates of physical inactivity were Asian, 28.1%; African, 23.5%; White, 17.4%; and Hispanic, 20.3%. For men, rates of inactivity were Asian 11.7%; African, 7.7%; White, 12.0%; and Hispanic, 13.8. Weight-training activity, youthful physical activity, and TV viewing accounted for a significant portion of the variance in physical activity levels (13.1% for women and 14.8% for men). The results of this study support the need for physical activity interventions for college students, particularly minorities.

The Long-Term Impact of a Four-Session Work-Site Intervention on Selected Social Cognitive Theory Variables Linked to Adult Exercise Adherence:

Many work-site physical activity interventions use theoretical variables in the design of their programs. Yet, these interventions do not document the degree of change in theoretical variables produced by the intervention. This study examined the construct validity of an intervention designed to affect social cognitive theory variables linked to exercise behavior. Construct validation methods were used to evaluate an instructional intervention composed of four 60-minute sessions delivered across 2 weeks. Increases were found in self-regulation skills, outcome-expectancy values, and self-efficacy for the treatment group. No significant increases were detected for the comparison group on any study variables. Sixty-seven percent of the treatment group was able to maintain exercise behavior across 12 months, whereas the comparison group declined in exercise participation from 68% to 25% across 12 months. The study revealed the intervention effective in producing the intended changes in social cognitive theory constructs. The analysis shows self-regulation-mediated exercise behavior.

A Meta-Analysis of Adolescent Psychosocial Smoking Prevention Programs Published Between 1978 and 1997 in the United States

Psychosocial smoking prevention studies have shown inconsistent results and theory-driven programs have been related to program success. This meta-analysis was used as a judgment tool for resolving these issues by estimating average program effects and investigating the relative efficacy of program types. The present study examined 65 adolescent psychosocial smoking prevention programs (1978 to 1997) among students in Grades 6 to 12 in the United States. Three program modalities (social influence, cognitive behavior, life skill) and two program settings (exclusively school based, school-community-incorporated) were identified as major a priori classifications. Knowledge had the highest effect sizes (.53) at short-term (≤ 1 year) but rapidly decreased (.19) at long-term(> 1 year). Behavioral effect was the most meaningful, being persistent over a 3-year period (.19 at ≤ 1 year; .18 at 1 to 3 years). Adolescent smoking reduction rates were increased by using either cognitive behavior or life skills program modalities, and/or a school-community-incorporated program setting.

Using the Health Belief Model to Predict Safer Sex Intentions among Adolescents

The purpose of this study was to use Health Belief Model (HBM) concepts to predict adolescents intentions to adopt safer sex behaviors. A stratified, random sampling technique was used to generate a sample of seventh-, ninth-, and eleventh-grade students representative of a southeastern state. A predictive model was constructed of the HBM variables. The model accounted for 43% of the variance in safer sex intentions among the seventh grade, 27% of the variance for the ninth grade and 17% of the variance for the eleventh grade. For the eleventh grade sample gender was the only significant predictor. The results of this study suggest that educational programs to promote safer sex intentions should focus on health related motivations among younger students. With older adolescents it may be more effective to expand education efforts to address factors directly relevant to their motivational schema and social environment. This study underscores the importance of using theory-based models in conducting health education research.

Harm reduction: an emerging new paradigm for drug education

Harm reduction is a new paradigm now emerging in the field of drug education. This strategy recognizes that people always have and always will use drugs and, therefore, attempts to minimize the potential hazards associated with drug use rather than the use itself. The rationale for a harm reduction strategy is presented, followed by an example of the kind of needs assessment which may be needed for planning a harm reduction strategy.

A worksite intervention to enhance social cognitive theory constructs to promote exercise adherence.

UNLABELLED The results suggest social cognitive theory variables associated with the adoption of exercise are changeable in a brief worksite intervention. Self-regulation techniques and outcome-expectancy value improved, but self-efficacy did not improve for the treatment group. One possible explanation is, the intervention did not adequately address the ability to overcome barriers to exercise faced by participants in the intervention. Another explanation may be the effect of experiencing the barriers to exercise faced by subjects during the first 4 weeks of a self-regulated exercise program. Before engaging in exercise, the participants had a perceived level of confidence to overcome barriers to exercise. Once faced with real barriers to exercise, the subjects may have reevaluated their ability to overcome these barriers. It is interesting that the comparison group reported small decreases in all social cognitive theory variables measured in this study. The comparison group received a program of assessment, instruction, and access to facilities that is common to many worksite-based fitness promotion programs. Clearly, this approach did not have a favorable impact on psychosocial variables associated with exercise adherence. These results may be explained by a reevaluation of beliefs and perceived capabilities to exercise, once faced with the real experiences and barriers related to the adoption of an exercise program. The small decreases in social cognitive theory variables in the comparison group may explain high dropout rates in many fitness center programs and warrant further study. IMPLICATIONS Health promotion specialists at the worksite need intervention programs that are safe, effective, and efficient for their employees. This intervention was based in the classroom, and no exercise was performed during class. This is appealing to employees who do not have access to shower facilities at the worksite. Moreover, in many interventions, subjects exercise during class and have limited time to learn specific skills to help them adopt and maintain exercise outside the structure of the intervention. Having established favorable changes in social cognitive theory constructs attributable to the intervention, a follow-up study should be conducted to determine the extent to which these changes predict adherence to regular exercise. These studies would establish the causal linkages between social cognitive theory constructs and regular exercise. LIMITATIONS There were specific limitations, and the results should be interpreted cautiously. The sample size was relatively small, although similar to other exercise intervention research reviewed by Dishman. Another limitation of the sample was no random assignment to treatment or comparison group. The results apply only to the subjects who volunteered for this study. The measure of outcome-expectancy value is the most vulnerable of those used to measure outcome expectations and outcome expectancies. It is possible that the results of the study would be substantially altered if a better measure were available. The data were collected through self-administered questionnaires. It was assumed the subjects would provide accurate information, but reliance on self-reported data introduces potential sources of error.

Stages of Change Among Ethnically Diverse College Students

Abstract The authors applied the stage-of-change construct in the transtheoretical model to examine the distribution of Asian (n = 869), African American (n = 373), White (n = 1322), and Hispanic (n = 535) American undergraduate students across the 5 stages of change for exercise. Stage of change varied as a function of ethnicity. Higher percentages of minorities were in the precontemplation and contemplation stages. The likelihood of being in these stages was from 43% to 82% greater for minorities than for White students. Also examined were the congruency between stage of change and self-reported levels of physical activity. Half of the sedentary students and 15.6% of the active students were misclassified by the stage-of-change procedure. Misclassification rates were higher for minority women (27.8%) than for White women (17.8%) and for Asian students (24.6%) compared with all others (20.6%). The results of this study have implications for the design of physical activity interventions based on stage of change.

Impact evaluation of a pilot web-based intervention to increase physical activity.

Purpose. The purpose of this pilot study was to conduct an impact evaluation of a 10-week Web-based physical activity intervention. Design. Quasi-experimental, three-group pretest, posttest design. Setting. Large Midwestern university. Subjects. Participants (N = 233) included college students registered for three courses. The study employed a convenience sample consisting of a Web-based group (n = 108), a physical activity group (n = 64), and a general health group (n = 61). Intervention. The Web-based group received a Social Cognitive Theory behavioral skill-building intervention and exercised 3 days per week in their leisure time. The physical activity group received exercise instruction and was required to attend three physical activity labs per week. The comparison group received health instruction. Measures. Outcome variables included moderate and vigorous physical activity, self-regulation, social support, self-efficacy, and outcome expectations and expectancies. Analysis. Differences between groups were assessed at pretest and posttest using multiple analyses of variance. Results. Vigorous physical activity, self-regulation, and outcome expectancy value changed significantly in the Web-based and physical activity course groups (p < .01). Conclusions. Even with consideration of limitations such as small sample size and lack of randomization, the Web-based and traditional physical activity lecture and activity lab interventions were superior in eliciting changes in vigorous physical activity, self-regulation, and outcome expectancy value than a traditional health course. (Am J Health Promot 2011;25[4]:227–230.)

Using Social Cognitive Theory to Predict Intentional Exercise in Post-Retirement Adults

Abstract No theory based studies have been done that explain why post-retirement adults are physically inactive. The purpose of this descriptive study was to test the ability of Social Cognitive Theory (SCT) constructs to predict intentional exercise among post-retirement adults. The sample consisted of 108 Columbus, Ohio area senior center members. Based on a six-month measure, the following model accounted for 52.3 percent of a variance in exercise: barriers to exercise, social support for exercise, exercise self-efficacy, benefits of exercise, and enjoyment of exercise. SCT was useful in predicting intentional exercise in post-retirement adults. It is suggested that exercise programs based on SCT be developed and tested on post-retirement adult populations.