The ActivitySnippets study will investigate the effects of short activity snippets on the sedentary behavior of bus and tram drivers. The main research question is: Do activity snippets increase the amount of time bus and tram drivers spend in a physically active state and reduce the amount of sedentary time during working hours? This research question will be investigated with a randomized controlled trial.

Physical inactivity is a global health burden and a major risk factor for noncommunicable diseases, which imposes a significant economic burden on health systems (Polo-López et al., 2024). On average, adults spend between 50 and 60% of their waking hours in sedentary behavior, with prolonged sitting significantly associated with increased all-cause mortality (Varela-Mato et al., 2015). Bus and tram drivers are particularly affected, spending up to 12 hours per day sitting, while also being exposed to work-related risk factors such as poor posture and strict schedules (Brodie et al., 2021; Varela-Mato et al., 2015).

Despite the availability of numerous health-promoting interventions for office workers, there is a lack of specialized, evidence-based health-promoting interventions tailored to the specific needs of bus and tram drivers. Research suggests that even short and low intensity physical activity can have health benefits (Koemel et al., 2024).

This research project aims to address the existing research gap by evaluating the effectiveness of short, simple and practical 'activity snippets' in reducing occupational physical inactivity among bus and tram drivers through a randomized controlled trial. Specifically, the study will investigate whether the implementation of activity snippets leads to a significant redistribution of sedentary time towards more active behavior compared to current World Health Organization (WHO) recommendations for physical activity.

A total of 75 bus and tram drivers from "Stadtwerke Krefeld", a public transport company in North Rhine-Westphalia (Germany), will be recruited to participate. At baseline, participants will wear an activity tracker for 10 days to measure acceleration, heart rate and other relevant parameters. Standardized and validated methods will be used to assess body composition, physical activity levels, strength and mobility. Participants will then be randomly assigned to either the intervention or control group.

The intervention group will receive a set of activity snippets for 16 weeks, consisting of a series of short exercises designed to improve muscle strength, increase activity levels at work and reduce stress. The control group will receive the latest WHO recommendations for physical activity. Throughout the intervention period, the research team will provide regular telephone support to ensure adherence, and both groups will wear an activity tracker for 10 days. Following the 16-week intervention, all baseline measures will be repeated, and user experience and acceptability of the activity snippets will be assessed. At the end of the study, participants in the control group will also be given access to the activity snippets. To assess potential long-term effects, a voluntary follow-up assessment, including 10 days of activity tracking, will be conducted three months after the end of the study.

This study aims to provide robust scientific evidence on the effectiveness of activity snippets in reducing prolonged sedentary time and increasing physical activity, and to assess their feasibility in the everyday working lives of bus and tram drivers. In addition, the findings could provide a basis for wider implementation in other inactive occupational groups. Ultimately, this research contributes to the advancement of both occupational and public health promotion strategies and supports the development of sustainable, evidence-based workplace interventions.

Inclusion criteria:

• men and women
• Employees who are actively working as bus or tram drivers for the company "Stadtwerke Krefeld".

Exclusion criteria:

• Persons who work in other areas of the company "Stadtwerke Krefeld".
• Persons who are not actively employed as bus and/or tram drivers.
• Bus and/or tram drivers employed by other companies or subcontractors
• Persons who have not agreed in writing to take part in the study.
• Persons who have not signed the loan agreement for the activity tracker.

Upon reasonable request, selected study data will be shared.