24h movement behaviours in university students compared to working age and older adults: wearable-based evidence and cardiometabolic health implications.
University students accumulated the most sedentary behaviour and lowest physical activity and sleep compared to working-age and older adults, and reallocation of time toward greater PA, less SB, and longer sleep was associated with lower cardiometabolic risk.
Key Findings
Results
University students had the highest sedentary behaviour and lowest physical activity and sleep of all three age groups studied.
University students (mean age 19.9 years, n=500) accumulated mean 633.89 min/day of sedentary behaviour, 320.28 min/day of physical activity, and 431.75 min/day of sleep.
Older adults (mean age 74.0 years, n=1,030) accumulated the least sedentary behaviour (500.86 min/day) and the greatest physical activity (420.28 min/day) and sleep (455.62 min/day).
These findings challenge the conventional expectation that older adults are less active and more sedentary than young adults.
Results
Reallocating 30 minutes per day to physical activity from other behaviours was associated with lower BMI, body roundness index, pulse wave velocity, and a composite vascular health score.
Reallocating 30 min/day to PA was associated with lower BMI (-0.13 kg/m²), BRI (-0.04), PWV (-0.05 m/s), and zComposite (-0.01).
Associations were estimated using compositional data regression models applied across 1,967 adults.
Physical activity, sedentary behaviour, and sleep were measured over 4 weeks using Oura Ring wearable devices.
Cardiometabolic outcomes assessed included BMI, body roundness index (BRI), pulse wave velocity (PWV), and a composite vascular health score (zComposite).
Results
Reallocating 30 minutes per day from sedentary behaviour to other behaviours was associated with lower BMI and body roundness index.
Reallocating 30 min/day from SB to other behaviours was associated with lower BMI (-0.28 kg/m²) and BRI (-0.07).
The magnitude of BMI reduction from reducing sedentary behaviour (-0.28 kg/m²) was larger than that from increasing physical activity (-0.13 kg/m²).
Compositional data regression models were used to estimate these associations.
Data were drawn from three Singaporean cohorts totalling 1,967 adults.
Results
Reallocating 30 minutes per day to sleep from other behaviours was associated with lower BMI and body roundness index.
Reallocating 30 min/day to sleep was associated with lower BMI (-0.21 kg/m²) and BRI (-0.05).
Sleep was measured objectively over 4 weeks using Oura Ring wearable devices.
University students had the least sleep of all three groups at a mean of 431.75 min/day (approximately 7.2 hours).
Associations were estimated using compositional data regression models.
Methods
The study used a compositional data approach with 4 weeks of wearable device data from 1,967 adults across three distinct life-stage cohorts in Singapore.
Three cohorts were studied: university students (n=500, mean age 19.9[1.3] years), working-age adults (n=437, mean age 41.1[10.0] years), and community-dwelling older adults (n=1,030, mean age 74.0[2.6] years).
Each participant contributed 4 weeks of Oura Ring recordings capturing time spent in physical activity, sedentary behaviour, and sleep.
Cardiometabolic outcomes assessed were BMI, body roundness index (BRI), pulse wave velocity (PWV), and a composite vascular health score (zComposite).
A compositional data regression modelling approach was used to account for the co-dependent and time-constrained nature of 24-hour movement behaviours.
Discussion
Young adulthood is identified as a critical and under-recognised period for interventions targeting physical activity promotion and sedentary behaviour reduction.
University students exhibited lower physical activity and higher sedentary time than older adults, contrary to conventional expectations about age-related inactivity.
The authors describe young adulthood as 'a critical, under-recognised target for interventions to promote PA and reduce SB for long-term health.'
Contemporary social, occupational, and educational environments may have altered expected age-related patterns of movement behaviour.
All three movement behaviours (PA, SB, sleep) showed independent associations with at least some cardiometabolic outcomes.
What This Means
This research suggests that university students—not older adults—have the most unhealthy movement patterns among adults, spending the most time sitting and the least time being physically active and sleeping. Using four weeks of wrist-worn device data from nearly 2,000 Singaporean adults across three age groups (university students, working-age adults, and older adults aged ~74), researchers found that students averaged over 10.5 hours of sedentary time per day, compared to around 8.3 hours for older adults. This overturns the common assumption that young people are more active and that sedentary lifestyles are primarily a concern for older age groups.
The study also found that shifting time from sedentary behaviour toward physical activity or sleep was linked to better measures of body composition and vascular health. For example, replacing 30 minutes of sitting per day with other activities was associated with a reduction of 0.28 kg/m² in BMI, while adding 30 minutes of physical activity or sleep was also associated with lower BMI and body fat estimates. These associations were seen even when accounting for the interconnected nature of daily time use—since time spent on one behaviour necessarily comes at the expense of another.
This research suggests that public health efforts to reduce sitting and increase movement should not focus solely on older populations. University students appear to be at particularly high risk for sedentary lifestyles, likely due to the demands of academic study and screen-based activities. Targeting this life stage with interventions to promote physical activity, reduce sedentary time, and improve sleep may have important long-term health benefits.
Ong J, Qin S, Martin T, Chua X, Soon C, Yilmaz G, et al.. (2026). 24h movement behaviours in university students compared to working age and older adults: wearable-based evidence and cardiometabolic health implications.. BMC medicine. https://doi.org/10.1186/s12916-026-05192-1