Abstract
<sec> <title>BACKGROUND</title> <p>Diet and physical activity (PA) are commonly considered together in public health guidance, with unhealthy diets and physical inactivity recognised as major modifiable risk factors for noncommunicable diseases. Time is central to the everyday practice of these behaviours, with lack of time often cited as a barrier to both being physically active and eating well. While 24-hour time-use diary data have been applied in public health research to examine health-related behaviours across the day, there is limited synthesised evidence on how food- and PA-related behaviours have been examined, operationalised, and situated within the wider 24-hour day.</p> </sec> <sec> <title>OBJECTIVE</title> <p>This scoping review aims to i) map the range of food- and PA-related behaviours examined using 24-hour time-use diary data, ii) characterise how these behaviours have been operationalised, and iii) examine how they have been situated within the wider 24-hour day, including alongside other daily activities, contextual factors and health-related variables.</p> </sec> <sec> <title>METHODS</title> <p>The review protocol is registered with OSF Registries and follows JBI methodology for scoping reviews. The completed review will be reported using PRISMA-ScR. A comprehensive search will be conducted across five databases: MEDLINE, Embase, PsycINFO, Scopus, and Web of Science Core Collection. Eligible studies will include published, peer-reviewed empirical studies of free-living individuals using diary-based activity records covering at least one complete 24-hour day to examine food- and/or PA-related behaviours. Two independent reviewers will screen titles and abstracts and subsequently assess full-text articles against the eligibility criteria. Data will be charted and summarised in tables and a narrative summary.</p> </sec> <sec> <title>RESULTS</title> <p>The literature searches, conducted in June 2026, identified 2,082 records, of which 825 remained after duplicate removal. Title and abstract screening is ongoing. Full-text assessment, data charting, and synthesis will be undertaken according to the methods described in this protocol.</p> </sec> <sec> <title>CONCLUSIONS</title> <p>This review will be the first to synthesise current evidence on how food- and PA-related behaviours have been examined, operationalised and situated within the wider 24-hour day in time-use diary research. The findings will clarify existing methodological approaches and evidence gaps, providing a foundation for future empirical studies using time-use diary data in this area.</p> </sec> <sec> <title>CLINICALTRIAL</title> <p>OSF Registries osf.io/xaryp; https://osf.io/xaryp</p> </sec>