A Research Agenda to Examine the Efficacy and Relevance of the Transtheoretical Model for Physical Activity Behavior

How big is the physical activity intention-behaviour gap? A meta-analysis using the action control framework

OBJECTIVES

The physical activity (PA) intention-behaviour gap is a topic of considerable contemporary research, given that most of our models used to understand physical activity suggest that intention is the proximal antecedent of behavioural enactment. The purpose of this study was to quantify the intention-PA gap at public health guidelines with a meta-analysis of the action control framework.

DESIGN

Systematic review and meta-analysis.

METHODS

Literature searches were conducted in July 2012 among five key search engines. This search yielded a total of 2,865 potentially relevant records; of these, 10 studies fulfilled the full eligibility criteria (N = 3,899).

RESULTS

Random-effects meta-analysis procedures with correction for sampling bias were employed in the analysis for estimates of non-intenders who subsequently did not engage in physical activity (21%), non-intenders who subsequently performed physical activity (2%), intenders who were not successful at following through with their PA (36%), and successful intenders (42%). The overall intention-PA gap was 46%.

CONCLUSION

These results emphasize the weakness in early intention models for understanding PA and suggest this would be a problem during intervention. Contemporary research that is validating and exploring additional constructs (e.g., self-regulation, automaticity) that augment intention or improving the measurement of motivation seems warranted.

STATEMENT OF CONTRIBUTION

What is already known on this subject? Intention is considered the proximal antecedent of behaviour in many popular models. Intention is also an established correlate of physical activity behaviour, yet discordance is considerable in experimental research. What does this study add? This meta-analysis of studies that have assessed concordance/discordance of physical activity intention and behaviour at public health guidelines shows the intention-behaviour gap at 48% and the discordance is from intenders who do not act. The results demonstrate that discordance is not just from extreme levels of intention or behaviour (e.g., intend to exercise six times but only exercise five), but from levels that are relevant to health promotion.

Body satisfaction is associated with Transtheoretical Model constructs for physical activity behavior change

Despite advancements in health behavior theory and practice, less than half of the United States population meets physical activity recommendations. Two cross-sectional studies (n=432; n=1455) were conducted to explore associations between body satisfaction and Transtheoretical Model (TTM) constructs proposed to explain the physical activity behavior change process. A series of regression analyses were conducted, controlling for demographic and TTM variables, as appropriate. Results indicate that body satisfaction significantly explains 2-8% of variance in the TTM constructs responsible for promoting stage movement. Furthermore, body satisfaction was significantly associated with stages of change representing short (>6 months) and long-term (>5 years) maintenance of physical activity. Future research should continue to examine these construct relationships using more rigorous research designs, with the ultimate goal of implementing body satisfaction components alongside traditionally effective TTM interventions to improve physical activity maintenance.

Stages of change, barriers, benefits, and preferences for exercise in RA patients: a cross-sectional study

OBJECTIVES

To determine the distribution of exercise stages of change in a rheumatoid arthritis (RA) cohort, and to examine patients' perceptions of exercise benefits, barriers, and their preferences for exercise.

METHODS

One hundred and twenty RA patients who attended the Rheumatology Unit of a University Hospital were asked to participate in the study. Those who agreed were administered a questionnaire to determine their exercise stage of change, their perceived benefits and barriers to exercise, and their preferences for various features of exercise.

RESULTS

Eighty-nine (74%) patients were finally included in the analyses. Their mean age was 58.4 years, mean RA duration 10.1 years, and mean disease activity score 2.8. The distribution of exercise stages of change was as follows: precontemplation (n = 30, 34%), contemplation (n = 11, 13%), preparation (n = 5, 6%), action (n = 2, 2%), and maintenance (n = 39, 45%). Compared to patients in the maintenance stage of change, precontemplators exhibited different demographic and functional characteristics and reported less exercise benefits and more barriers to exercise. Most participants preferred exercising alone (40%), at home (29%), at a moderate intensity (64%), with advice provided by a rheumatologist (34%) or a specialist in exercise and RA (34%). Walking was by far the preferred type of exercise, in both the summer (86%) and the winter (51%).

CONCLUSIONS

Our cohort of patients with RA was essentially distributed across the precontemplation and maintenance exercise stages of change. These subgroups of patients exhibit psychological and functional differences that make their needs different in terms of exercise counselling.

Transtheoretical Model Constructs for Physical Activity Behavior are Invariant across Time among Ethnically Diverse Adults in Hawaii

OBJECTIVES: Physical activity (PA) research applying the Transtheoretical Model (TTM) to examine group differences and/or change over time requires preliminary evidence of factorial validity and invariance. The current study examined the factorial validity and longitudinal invariance of TTM constructs recently revised for PA. METHOD: Participants from an ethnically diverse sample in Hawaii (N=700) completed questionnaires capturing each TTM construct. RESULTS: Factorial validity was confirmed for each construct using confirmatory factor analysis with full-information maximum likelihood. Longitudinal invariance was evidenced across a shorter (3-month) and longer (6-month) time period via nested model comparisons. CONCLUSIONS: The questionnaires for each validated TTM construct are provided, and can now be generalized across similar subgroups and time points. Further validation of the provided measures is suggested in additional populations and across extended time points.