Behaviour-change techniques for activity: across 122 interventions, self-monitoring plus at least one other control-theory technique (goals, feedback, review) was the effective core (d 0.42 vs 0.26)
Key Findings
122 evaluations of physical-activity and healthy-eating interventions in adults (experimental or quasi-experimental; 44,747 participants in total), coded into 26 behaviour-change techniques; overall pooled effect size 0.31 (95% CI 0.26–0.36, I² = 69%).
Self-monitoring explained the most between-study heterogeneity (13%). Interventions combining self-monitoring with at least one other control-theory technique (goal-setting, feedback, review of goals, prompting intention formation — the technique family; the exact list is full text) were significantly more effective than the rest: 0.42 vs 0.26. The effective unit is the self-regulation loop, not any single trick.
Not from this paper (related work): Samdal 2017 (DOI 10.1186/s12966-017-0494-y) and Kwasnicka 2016 (DOI 10.1080/17437199.2016.1151372) separate techniques for *initiation* from those for *maintenance* (motives, self-regulation, resources, habit, environment); Gollwitzer & Sheeran 2006 (DOI 10.1016/S0065-2601(06)38002-1) on if-then plans closing the intention–action gap — none of these three checked against its abstract here.Lally 2010 (DOI 10.1002/ejsp.674; checked against its abstract): 96 volunteers repeating a chosen daily behaviour for 12 weeks; time to reach 95% of their automaticity asymptote ranged from 18 to 254 days, and missing one opportunity did not materially affect habit formation (the often-quoted 66-day median is from the full text, not the abstract).
Practical Application
In 122 interventions, the ones that paired self-monitoring with goal-setting/feedback/review were markedly more effective (0.42 vs 0.26). Build that loop by default: specific goal → self-monitor (log, sRPE, planned-vs-actual) → feedback → review/adjust. Blocks' plan-vs-actual and sRPE surfaces are this loop.
Add action and coping planning (if-then rules for derailers: bad weather → trainer; short on time → key set only). (Not from this paper; the base's own practice, drawing on Gollwitzer & Sheeran above.)
Anchor sessions to stable cues and expect habit to take weeks to months (Lally: 18–254 days to plateau); treat initiation and maintenance as different problems. (Not from this paper.)
Limitations
Heterogeneous interventions (I² = 69%); techniques coded with the 26-item pre-2013 taxonomy (coarse); general-population adults (Tier 1–2), so committed athletes may differ.
How this entry was checked and changed
Content correction 2026-09-27
Added the abstract's numbers: 122 evaluations, 44,747 participants, pooled ES 0.31 (0.26–0.36), self-monitoring explaining 13% of heterogeneity, 0.42 vs 0.26 for self-monitoring + control-theory technique.
Lally 2010 "median ~66 days" labelled as full text (its abstract gives only the 18–254-day range and 96 volunteers); the other secondary citations marked as not checked; house advice labelled.