1 | 39 Synthesis to provide a high level of flexibility and autonomy and hence the opportunity to practise sport where, when, how often, how long and with whom suits best, as the major life events generally cause a decrease in temporal resources. “Light” individual and unorganised sport activities as well as informal group activities meet these conditions best. A lot of these sport activities take place in public spaces and can therefore be promoted by investing in an attractive and safe sport infrastructure. For example, green areas (e.g., parks, woods, riversides) with drinking fountains and good lighting, workout facilities (e.g., a calisthenics or fitness park), pitches suitable for practising field sports like football, basketball and volleyball, and cycling paths and running tracks with signposted routes within and between these green areas. Local sport providers could also make use of these facilities or create “do-it-yourself” sport tutorials or courses (e.g., online videos or information signs), to empower people to practise sport in these public spaces. Sport providers who normally offer more “heavy” and organised activities, like commercial health and fitness centres and sport clubs, could also offer such “do-it-yourself” tutorials or courses as more flexible and autonomous alternatives. Further, they might offer various and more flexible contribution and membership options, like paying-per-session, a ten-session credit card, subscriptions for specific times (e.g., for off peak hours) or periods (e.g., a summer or winter subscription), and memberships that can be “paused” and “resumed” at any time. Secondly, as young adults commit to their new, more adult roles and the related responsibilities and activities are generally prioritised over sport participation, it is important to provide sport concepts that do not impede and preferably even facilitate or incorporate these new roles, responsibilities and activities. From this perspective, sport activities that are tailored to be easily or intelligently combined with or linked to new event-related activities and responsibilities (e.g., studying, work, childcare and quality time with significant others), can empower people to sustain sport participation during the transition to adulthood. These activities do not only fit the decrease in temporal resources (i.e., as they are very time-efficient), but also the reconfiguration of other resources during the transition to adulthood; social resources in particular. Making such “smart combinations” can be facilitated and promoted, by making study and work environments “sport friendly”, and by making sport environments “study, work and family friendly”. Universities already seem to succeed in this, with on-site sport facilities, a wide range of sport activities, and beneficial sport arrangements, privileges and discounts