Abstract Aim This study aimed to evaluate factors affecting older adults’ participation in a blended physical activity (PA) intervention, which comprised tailored home-based exercises and supervised on-site group sessions with peers. Specifically, the objective was to explore participants’ feedback for identifying specific requirements regarding intervention components and materials. Subject and methods In a 9-month randomized trial with a cross-over design targeting adults aged 60 and above, web- and print-based materials to promote PA were enhanced based on results of a preceding trial, and tested in n = 242 participants. Use of these adapted program components, attendance of group sessions, and acceptance of the intervention were assessed via self-administered paper-based questionnaires 3 and 9 months after baseline, as well as in interviews and group sessions. Participant feedback was analyzed via qualitative content analysis of open-ended questions, group interviews, and protocols. The social–ecological model served as a coding framework. Results Feedback covering six different levels of requirements according to the social–ecological model was analyzed. The content of the program, including the option to track perceived progress in PA, health, and fitness, as well as the group-based components, providing opportunities for social support, and training with the peer group, were appreciated by participants. Criticism and suggestions for improvement were provided with regard to instructors of the group sessions, the group atmosphere, space requirements, program scheduling, and communication. Conclusions Based on various sources of participant feedback, several requirements and recommendations regarding future characteristics of PA interventions targeting older adults in community settings can be provided.