Defense Date


Document Type


Degree Name

Master of Public Health


Epidemiology & Community Health

First Advisor

Dr. May Kennedy


Background: The majority of Americans - especially women - do not meet physical activity recommendations. Having physical activity goals has been associated with physical activity participation, and physical activity recommendations set by public health experts can be viewed as externally set goals. However, past research has shown that goals that are specific rather than ambiguous are more likely to be achieved, and variations in recommendations over time and across sources may have created perceived goal ambiguity.Objectives: This study aimed to (1) examine the extent of physical activity recommendation knowledge among adults in the United States, (2) quantify perceptions of the ambiguity of these recommendations, (3) determine whether knowledge of physical activity recommendations is associated with physical activity level, and (4) investigate whether perceived ambiguity of recommendations moderates the relationship between recommendation knowledge and activity. An additional objective was to explore demographic differences in any associations detected.Methods: SUDAAN was used to weight data from the 2005 Health Information National Trends Survey (HINTS) (N=5,586) to represent the U.S. population. Descriptive statistics were calculated, and logistic regression was used to determine crude and adjusted odds ratios.Results: An estimated 31% of Americans had accurate knowledge of recommendations, and 35% reported engaging in physical activity at the recommended level. An estimated 75% perceived the recommendations as ambiguous. The odds of reporting accurate knowledge of recommendations were significantly higher among women than among men (OR 1.53,95% CI 1.22-1.93), but accurate knowledge of recommendations was associated with physical activity at the recommended level only among men (OR 1.67,95% CI 1.06-2.64). Perceived ambiguity did not moderate the association between knowledge and activity level in any analysis.Conclusions: These findings support disseminating updated physical activity recommendations as indicated by the scientific evidence base. Future research should explore: (1) how to boost knowledge of recommendations, particularly in men, (2) factors that would enable women to act on such knowledge, and (3) gender differences in other determinants of physical activity.


© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

June 2008

Included in

Epidemiology Commons