Objective To examine older adult physical activity (PA) intervention studies that evaluated implementation and/or scale-up. Research question 1: What implementation and/or scale-up indicators (specific, observable and measurable characteristics that show the progress of implementation) were reported? Research question 2: What implementation and/or scale-up frameworks were reported? Research question 3: Did studies evaluate the relationship between implementation or scale-up of the intervention and individual level health/behaviour outcomes? If yes, how?

Design Systematic review.

Data sources Publications from electronic databases and hand searches (2000 to December 2019).

Eligibility criteria for selecting studies Any PA intervention studies with community-dwelling older adult participants (mean age ≥60 years). Required indicators: (a) Must report amount of PA as an outcome, with validated self-report or objective measures, and (b) Must have reported at least one implementation or scale-up framework and/or one implementation or scale-up indicator.

Results 137 studies were included for research question 1, 11 for question 2 and 22 for question 3. 137 studies reported an implementation indicator: 14 unique indicators. None were specified as indicators for scale-up evaluation. 11 studies were guided by an implementation or scale-up framework. 22 studies described a relationship between an implementation indicator and an individual-level health outcome.

Conclusion There is need for implementation research that extends beyond analysis at the individual level, includes clearly defined indicators and provides a guiding framework to support PA initiatives in older adults. Such implementation studies should evaluate factors in the broader context (eg,political, environmental) that influence scale-up.

PROSPERO registration CRD42018091839