Pedro Teixeira
Pedro J. Teixeira is a Portuguese exercise psychologist and professor at the University of Lisbon. He is the first author of Teixeira, Carraça, Markland, Silva and Ryan (2012), the systematic review of self-determination theory applied to exercise, published in the International Journal of Behavioral Nutrition and Physical Activity. It is the bridge between an abstract motivation framework and what happens to people who join a gym, and it is the citation that should anchor any argument about motivation and exercise on this site. Richard Ryan is a co-author, which is how the finding routinely ends up credited to Deci and Ryan. It is Teixeira's review.
Who they are
Teixeira's field is the applied end of motivation science: weight management, physical activity and the behaviour-change interventions built on them. His contribution to the vault is a synthesis rather than a new construct, and synthesis is what the subject most needed, because the exercise literature had accumulated decades of individual studies without anybody organising them around a coherent theory of motivation.
Reviewing that literature through autonomy, competence and relatedness reorganises it. What predicts somebody still training a year later turns out not to be how badly they wanted to start.
Key papers
Teixeira, P. J., Carraça, E. V., Markland, D., Silva, M. N., & Ryan, R. M. (2012). "Exercise, physical activity, and self-determination theory: a systematic review", International Journal of Behavioral Nutrition and Physical Activity, 9:78. DOI 10.1186/1479-5868-9-78. First author.
Design: a systematic review of 66 empirical studies to June 2011, mixed experimental, cross-sectional and prospective.
Finding: a consistent positive relation between autonomous forms of motivation and exercise, with a distinction worth keeping. Identified regulation, doing it because it matters to you, predicts early adoption more strongly. Intrinsic motivation, doing it because the activity itself is enjoyable, predicts longer-term adherence. Those are two different motivations doing two different jobs at two different points, which is more useful to a reader than a single verdict about what makes exercise stick.
It is a narrative synthesis, so there is no pooled effect size and none should be invented for it.
Key ideas
The motivation that gets somebody to start is not the motivation that keeps them going, and the review's adoption-versus-maintenance distinction is the reason to cite it rather than a general statement about intrinsic motivation.
Autonomous motivation is reliably associated with exercise. That is an association, and the review is correlational in the main.
Two corrections this vault made to its own note on him, September 2026. The claim that intrinsic motivation is "the strongest predictor of long-term adherence" overstates the review, which distinguishes adoption from maintenance and does not rank predictors. And the review establishes association rather than cause.
For what interventions built on the theory actually achieve, the source is Nikos Ntoumanis's 2021 meta-analysis, which reports modest and heterogeneous effects.
Concepts on this site
Self-Determination Theory, the framework his review applies
Exercise Adherence, the domain
Identity-Based Habits, adjacent
Sources
- Teixeira, P. J., Carraça, E. V., Markland, D., Silva, M. N., & Ryan, R. M. (2012). International Journal of Behavioral Nutrition and Physical Activity, 9:78. DOI 10.1186/1479-5868-9-78.
- Ntoumanis, N., et al. (2021). Health Psychology Review, 15(2), 214 to 244. The intervention evidence.
- Vault verification record, 2026-09-11. Citation recorded in full, the overstated adherence claim corrected, and the credit noted as his rather than Ryan's.