Editorial: Advancing physical activity behavior change: the potential of serious digital health technologies

The Global Action Plan on Physical Activity (PA) targeted a 15% relative reduction in physical inactivity levels by 2030 [1]. Yet despite widespread PA guidelines, the global prevalence of insufficient PA remains high and continues to rise [2]. This persistent gap shows that generic recommendations alone are insufficient to trigger lasting behavior change [3]. Given the major individual and societal consequences of physical inactivity [4], this Research Topic addresses a central question: how and under what conditions can DHTs (i.e., an umbrella term for digital technologies applied in the context of health, including eHealth, mHealth, telehealth, and artificial intelligence (AI) [5]) that are purposefully designed promote lasting health behavior change?A central message emerging from this Research Topic is that DHTs are best understood not as behavior change interventions in themselves, but as delivery vehicles whose effectiveness depends on how they are designed, embedded, and supported.Baumann et al.'s bibliometric trend and network analysis of 2,981 articles anchors this Research Topic. They document the rapid expansion of mobile and wearable DHTs for PA promotion in the 2010s, reflecting accessible PA self-monitoring advancements. However, more structured support is required, as Adorni et al. demonstrated with appropriately timed, user-sensitive, and interactive communication grounded in the Health Action Process Approach [6] that produced more sustained PA increases than self-monitoring. This finding aligns with broader evidence that DHTs can support habit formation at scale [7,8] -provided they offer clear cues, immediate rewards, and repeated opportunities for action [9], for which DHTs offer practical appeal via behavioral prompts, continuous feedback, and remote monitoring and tailoring.Initiating habit formation is a challenge. Sustaining improved health behavior is arguably even more challenging. Hart et al.'s protocol addresses this challenge methodologically through a two-stage randomization, allowing examination of both initial habit formation and the role of personalized digital support grounded in the Behavior Change Wheel [10] in maintaining PA after moderate-to-severe traumatic brain injury. For sustaining general PA over ≥ 1 year, Li and Dong's findings on psychosocial mechanisms in adolescents reinforce that lasting behavior change cannot be reduced to behavioral prompts and rewards alone; programs must also foster perceived control, self-confidence, and social support. Glatt et al.'s "brain gym" integrated these principles in a community-based senior living environment grounded in Self-Determination Theory [11]. By combining gamification, graded task progression, real-time feedback, and social facilitation, 67% met criteria for sustained adherence over 12 months. Although program frequency was low -<1x/week -this contribution is notable because long-term engagement persists as challenge while evidence on feasible community-based solutions remains rare 45 [12]. This fragmentation is reflective of the wider literature, where overlapping concepts are pursued under separate labels with limited 71 cross-referencing across these silos. This is especially prevalent for different DHT subconstructs [5] and gamified DHTs (i.e., 72 exergames) that are referred to under various terms [12]. 73 Therefore, the field's next maturation step may be less about continuing to produce isolated studies and more about conceptual 74 and methodological consolidation across these silos. Efforts toward shared taxonomies (e.g., [12,15]