The Transtheoretical Model of Behavior Change (TTM) was originally developed by James O. Prochaska and Carlo C. DiClemente for understanding the stages and processes of smoking cessation and over the past 3 decades has been broadly applied for understanding change across a variety of behaviors, including exercise and physical activity. The TTM was developed to be comprehensive model of behavior change by including cognitive, behavioral, and temporal components into a single framework for behavior change. The five components within the TTM are stages of change, processes of change, self-efficacy, decision balance, and temptation. Stages of change classify one’s preparedness and progress toward behavior change, and progress is directed by the other four TTM components. Indeed, processes of change, self-efficacy, decision balance, and temptation differ in level and importance among stages, and can be guiding pillars of interventions for promoting progression and preventing regression of individualized behavior change.
The stages of change characterize the preparedness or readiness dimension into five progressive stages or timelines along which behavior change occurs. The first stage is precontemplation and includes persons with no intention of change within the next 6-month period. Essentially, the person has not even considered behavior change. The second stage is contemplation wherein the person has considered behavior change within the next 6-month period. Essentially, the person has begun thinking about a change in behavior.
The third stage, preparation, describes a person who possesses immediate intentions, plans, and commitment for changing behavior (e.g., within next month) but has not done so yet. This is followed by the action stage wherein persons have initiated behavior change, but this change has been sustained for less than a 6-month period. The last stage is maintenance, wherein behavior change has occurred and been maintained for a prolonged period, for example, longer than 6 months. When considering behavior change, the goal is for individual progression from precontemplation through action stages, and, once action and maintenance are reached, prevention of relapse into an early stage. Importantly, persons can change by single stages or multiple stages (e.g., precontemplation → preparation). Such change occurs through the consideration and focus on the other four TTM components.
Processes of change have been categorized into broad groups of experiential or behavioral factors and represent the strategies adopted and targeted for stage progression or prevention of relapse when in action or maintenance. Experiential processes such as consciousness raising, like seeking new information about a problem behavior, and self-reevaluation, like appraising one’s values regarding a problem behavior, are gathered through personal experiences, whereas behavioral processes, such as stimulus control in controlling situations that trigger a problem behavior, and reinforcement management, like rewarding one’s self for changing a problem behavior, are developed through interactions with the environment or through action. Experiential processes are seemingly more important for progression in earlier stages, whereas behavioral processes have greater importance during later stages of change. The processes further are amenable for target by professionals and researchers for promotion of individualized behavior change.
Self-efficacy reflects one’s personal confidence or agency in successfully executing a course of action, or within the context of TTM, changing one’s behavior and progressing through stages. Self-efficacy seemingly increases with stage progression. Whereas the TTM does not explicitly identify targets for changing one’s self-efficacy, Albert Bandura has outlined performance accomplishment, vicarious experience (social modeling), verbal persuasion (social support), and physiological or affective states as variables for changing self-efficacy expectations. This permits self-efficacy to be a constructive target by professionals and researchers for promotion of individualized behavior change.
The last two components of the TTM are decision balance and temptations. Decision balance reflects a person’s beliefs and evaluation of the pros (benefits) and cons (costs) of engaging in a behavior, whereas temptation reflects negative urges toward withdrawing from a behavior change. Stage progression occurs as pros outweigh cons (benefits > drawbacks) and when temptations are minimized.
Collectively, individuals progress through stages of change by adopting experiential processes early (e.g., consciousness raising for moving from precontemplation → contemplation → preparation), and behavioral processes later (e.g., stimulus control for moving from preparation → action → maintenance). Self-efficacy is lowest with the early stages (e.g., precontemplation) and increases across stages (e.g., preparation → action) until it peaks with maintenance. Regarding decision balance, cons outweigh pros during early stages of precontemplation, contemplation, and preparation, for instance, and pros outweigh cons during later stages like action and maintenance. Finally, temptations are highest within the early stages (e.g., precontemplation) and decrease across stages (e.g., preparation → action) until its nadir with maintenance.
The TTM is appealing because it categorizes persons based on readiness for change and then provides concrete strategies and approaches for changing a health behavior. This has great appeal for highly individualized behavior change. The theoretical mechanisms for behavioral change included in the TTM are further applicable among diverse behaviors and populations. This has great appeal for adopting the TTM across multiple behaviors and person domains. An additional benefit is that the TTM is application for multiple-behavior change within a single program, and the appeal is that the effectiveness of multiple changes can be maximized within an individualized intervention.
The TTM is particularly appealing for applications involving change in physical activity and exercise behavior; this has been nicely described by Claudio Nigg and Simon Marshall. Importantly, exercise behavior can readily be considered as a dichotomous change process—that is engaging or not engaging in a prescribed exercise routine for a considerable time. The application for physical activity has been more difficult as this is often considered a continuous behavior, unless we apply the TTM for meeting public health guidelines for physical activity of 150 minutes of moderate-to vigorous physical activity per week. This is critical considering concerns directed toward applications of the TTM for understanding change in continuous variables such as physical activity behavior. Nevertheless, the TTM has major strengths in its potential for tailored applications regarding a person’s readiness for change in physical activity or exercise, particularly given the public health crisis of inactivity and sedentariness. This makes the TTM amenable for research-based interventions and practitioner-led applications involving individual change in these behaviors. For example, there may be big differences among people regarding their readiness for undertaking an exercise program: some may only be thinking about beginning a program, whereas others might be considering strategies for maintaining a morning exercise routine. Both groups of persons have the same goal of exercise or physical activity but require different information and processes, thereby necessitating different interventional or practitioner-based approaches. Indeed, the TTM is simple and clear enough that it can be adopted by any researchers or practitioners, such as nurses, social workers, psychologists, or physiotherapists.
There have been contentious issues when applying the TTM to physical activity and exercise behavior change, perhaps most importantly that the TTM was originally developed for cessation of a behavior (smoking with addictive properties), whereas its application for exercise and physical activity involves starting or adopting a new behavior with minimal addictive properties. Of further note, smoking is not performed with great energy expenditure above resting levels, whereas physical activity and exercise by definition must be performed with a substantial increase in energy expenditure. There are further conflicting intentions and goals between smoking cessation and starting physical activity behavior. These points must be considered for balancing enthusiasm toward applications of the TTM in physical activity and exercise applications and should encourage careful thought and consideration when it is applied within the promotion of this health behavior change.
- Bandura, A. (1977). Self-efficacy: Toward a unifying theory of behavior change. Psychological Review, 84, 191–215.
- Marshall, S. J., & Biddle, S. J. (2001). The transtheoretical model of behavior change: A meta-analysis of applications to physical activity and exercise. Annals of Behavioral Medicine, 23, 229–246.
- Nigg, C. R., Geller, K. S., Motl, R. W., Horwath, C. C., Wertin, K. K., & Dishman, R. K. (2011). A research agenda to examine the efficacy and relevance of the transtheoretical model for physical activity behavior. Psychology of Sport and Exercise, 12, 7–12.
- Prochaska, J. O., & DiClemente, C. C. (1983). Stages and processes of self-change of smoking: Toward an integrative model of change. Journal of Consulting and Clinical Psychology, 51, 390–395.
- Weinstein, N. D., Rothman, A. J., & Sutton, S. R. (1998). Stage theories of health behavior: Conceptual and methodological issues. Health Psychology, 17,290–299.