Abstract Issue/problem Physical activity is a protective factor for preventing Noncommunicable diseases (NCDs) and, for this reason, it plays an important role in all the different guidelines for prevention and health promotion. The Italian Regional Prevention Plans and in particular the Lombardy one promote physical activity with a systemic approach, through both upstream and downstream actions to encourage the role of communities. Description of the problem Based on the regional plan, the Health Protection Agency (HPA) of the Metropolitan City of Milan developed locally validated actions and best practices for the promotion of physical activity, through the cross-sectoral involvement of different stakeholders (health system, companies, universities, local authorities, sports associations, etc.). Results Physical activity is embedded in all lines of health promotion activities in local planning documents. Sustainable and active mobility activities have been implemented in companies and schools with a comprehensive approach. Validated regional programs (Pedibus, Walking Groups, ecc.) have been implemented in the local community, along with the construction of permanent local laboratories for physical activity, structured through the development of specific territorial networks and providing for integration with the socio-sanitary setting. Lessons Promoting physical activity becomes an opportunity to both consolidate territorial networks and to develop evidence-based health promotion actions able to meet the different health needs of the population and to produce a structural change in living contexts. Key messages • Physical activity is both a protective factor for health promotion and a tool for implementing intersectoral and equity-oriented system actions from a life-course perspective. • Promoting physical activity becomes an opportunity to consolidate territorial networks.