Physical activity levels in young adult Hispanics and Whites: Social cognitive theory determinants

Abstract

The psychosocial determinants of health-impairing physical inactivity among Hispanic populations have not been well explored nor have systematic comparisons been made with White populations using Social Cognitive Theory (SCT) measures. Three exercise-relevant efficacy measures (task, scheduling, and response efficacy), three exercise-relevant expectancy measures (physical health, psychological health, and self-evaluative), and self reports of activity levels were obtained from 20-year-old male and female Hispanics (n = 94) and Whites (n = 94). Activity levels for the two groups were analyzed in separate regression analyses that included the six SCT measures and gender as predictors. The set of seven predictors accounted for 51% of the variance in self-reported activity levels in each analysis. For young adult Hispanics, task efficacy, response efficacy, mental-health expectancies, and self-evaluative expectancies predicted activity level. For young adult Whites, scheduling efficacy and self-evaluative expectancies predicted activity level. Gender was not a significant predictor of activity level for either group. A multivariate analysis of variance indicated that the only SCT predictor on which Hispanics and Whites significantly differed was mental-health expectancies. The results of this study indicate that the psychosocial determinants of exercise are qualitatively different for the two groups and that the determinants of physical activity levels for young adult Hispanics may not be as effective as those of young adult Whites in sustaining lifelong exercise habits. Thus the present study offers a promising strategy for detecting inactivity-related physical- and mental-health risks at an age when lifelong habits of physical activity are still being formed.

Keywords:

• Efficacy beliefs
• expectancy beliefs
• physical activity
• young adults
• ethnicity

Acknowledgments

The author wishes to thank Melissa McVicker and Frank Rodriguez for their conscientious assistance in data coding and entry.

Notes

¹ Because no direct relationship between the accuracy subscale of the ESSQ and caloric expenditure has been previously reported in the literature, a separate study was conducted to demonstrate the validity of the accuracy subscale of the ESSQ as a predictor of self-reported exercise caloric expenditure. Thirty-eight males and forty-one females completed the six-item ESSQ and a modified version of the Aerobics Center Longitudinal Physical Activity Questionnaire (ACLPAQ, Kohl, Blair, Paffenbarger, Macera & Kronenfeld, 1988). The modified ACLPAQ first required participants to indicate the total number of minutes spent on ten different categories of physical activities during the previous seven days, resulting in a more structured version of the Stanford 7-Day Recall Interview (S7DRI, Sallis et al., 1985). Physical activity categories included jogging, treadmill use, bicycling, swimming, aerobic dance/calisthenics, moderate-intensity sports (volleyball, golf, dancing, doubles tennis), vigorous racquet sports (racquetball, singles tennis), vigorous running sports (basketball, soccer), weight training, and any other sports/recreational activities. Participants also estimated the total number of minutes for each activity category during an average week in the prior three months, providing a correction for the S7DRI's short-term focus. Where there were discrepancies between the two estimates, the one based on the three-month interval was used in computing typical weekly energy expenditures. The rate of energy expenditure for each activity in METs (where one MET is defined as the energy expenditure for sitting quietly) was obtained from Ainsworth et al. (1993). MET values for each activity were then multiplied by the total amount of time reportedly spent on the activity in a typical week in order to obtain a total estimate of energy expenditure in MET-hr/wk for each participant. The correlation between the accuracy subscale of the ESSQ and the rank-transformed MET-hr/wk estimate for each respondent is strong and highly significant, r(77) = 0.62, p < 0.001. The correlation between the accuracy subscale of the ESSQ and the number of different kinds of weekly physical activities reported by a respondent is also strong and highly significant, r(77) = 0.55, p < 0.001. Thus, the accuracy subscale of the ESSQ used here as a measure of self-reported activity level is a valid index of both the amount and variety of regular physical activity as measured by a more detailed physical activity inventory.

² The ESSQ is typically used to assess “exercise schematicity” as the degree to which being physically active is part of one's self-concept (Kendzierski, 1988, 1990, 1994). However, Bandura (1997, p. 10) has argued that “self-concept loses most, if not all, of its predictiveness when the influence of perceived efficacy is factored out.” The value of the ESSQ in the present study is that its importance items offer a measure of self-evaluative outcome expectancies. When one rates “being physically active” as important to one's self-image, behaviors congruent with that image should occasion self-reward, and behaviors incongruent with that image should occasion self-punishment (Bandura, 1997, pp. 283–284). In fact, Rovniak et al. (2002) find that their measure of such self-regulating behaviors is a strong predictor of physical activity in college students and adds significantly to the predictive power of self-efficacy measures. Therefore, the predictive value of exercise schematicity in previous studies of exercise behavior (e.g., Clark, 2002) may due to the fact that the importance items of the ESSQ tap self-evaluative outcome expectancies rather than some aspect of a physical self-concept.

³ In response to the suggestions of two anonymous reviewers, the three efficacy measures and the three expectancy measures were entered simultaneously into an overall regression analyses with all 188 participants so as to determine the unique contribution each variable makes to the prediction of self-reported physical activity. Main effects terms (gender, task efficacy, scheduling efficacy, response efficacy, physical-health expectancies, mental-health expectancies, and self-evaluative expectancies) and interaction terms (multiplying each main effect term by a dummy variable term coding ethnicity) were included in order to examine ethnic differences in the relative importance of the SCT predictors. Unfortunately, significant multicollinearity problems resulted from the inclusion of these interaction terms, as indexed by the variance inflation factor (VIF values ranging from 6.40 to 31.02, with a median VIF value of 17.81). Kleinbaum, Kupper and Muller (1988, p. 210) note that any VIF larger than 10.0 is a matter of concern, making it difficulty to obtain reliable estimates of partial slope estimates. The problem is mitigated to some extent in these data by including only the interaction terms in the overall regression analysis, but is not satisfactorily resolved (VIF values ranging from 1.83 to 16.63, with a median VIF value of 9.58). Therefore, as recommended by Skaff et al. (2003, p. 303), ethnic differences were examined in this study by conducting separate regression analyses for the Hispanic and White samples. This approach also allows for a clearer conceptual representation of ethnic differences within the SCT theoretical framework.

⁴ Dr E. W. Stanzcak, Executive Director of Health & Counseling Services, The University of Texas at San Antonio, reports that 43% of the students making use of their services this past year were Hispanic and 45% were White. The Hispanic student enrollment during that period of time was 45%, and the White enrollment was 41%.