Background: University students may remain sedentary for large parts of the day, spending >9 hours per day sitting. Prolonged sitting is associated with increased risk for adverse health outcomes in adulthood. Light-intensity physical activity (LIPA) can be integrated into university students’ daily routines to counteract the negative effects of prolonged sitting on cognitive function and musculoskeletal health. Objective: This protocol describes a trial conducted in Singapore to evaluate the acute (immediate) and short-term delayed effects of two 5-minute LIPA modalities (sit-cycling [S-C] and stand-twisting [S-T]) on neurocognitive and somatic outcomes (prefrontal cortical oxygenation, cognitive performance, subjective sleepiness, and back pain) in physically inactive university students compared to a modality-matched passive control condition. Methods: The study comprised a main study (N=22) and a methodological substudy (n=6, 27.3%). In the substudy, students’ oxygen uptake was measured during 5-minute bouts of S-C and S-T to verify that both modalities meet the operational definition of LIPA. In the main study, physically inactive university students were allocated in a 1:1 ratio to either S-C or S-T (between-participant factor). Each participant completed two laboratory visits within their assigned modality: an experimental LIPA visit and a corresponding modality-matched passive control visit of equal duration (passive sitting for S-C and S-T), enabling within-person intervention-control comparisons. The primary endpoint is the change in bilateral dorsolateral prefrontal cortex (DLPFC) oxygenated hemoglobin (O2Hb) from baseline to immediately after the intervention during cognitive task performance (intervention vs control), measured with functional near-infrared spectroscopy (fNIRS). Secondary outcomes include O2Hb persistence at 20 minutes postintervention, cognitive performance (n-back test and Stroop Color and Word Test [SCWT]), subjective sleepiness, and back pain. Results: The study was funded by the Sendai University International Collaborative Research Grant in April 2023, and the trial was registered with ClinicalTrials.gov on November 21, 2024. Participant recruitment and data collection were completed in December 2024. The substudy results showed that both 5-minute S-C and S-T bouts fell within the LIPA range of <3 metabolic equivalents (METs) and could be implemented as brief, standardized LIPA breaks in the main trial. For the main trial, data cleaning and preliminary analyses are ongoing, and the outcomes will be reported in a subsequent outcomes paper (anticipated in late 2026). Conclusions: This protocol provides a prespecified framework to test whether brief 5-minute LIPA bouts may be a practical strategy to interrupt prolonged sitting and acutely improve prefrontal oxygenation and related neurocognitive and somatic outcomes in physically inactive university students. Trial Registration: ClinicalTrials.gov NCT06703424; https://clinicaltrials.gov/study/NCT06703424 International Registered Report Identifier (IRRID): PRR1-10.2196/82510

BACKGROUND University students may remain sedentary for large parts of the day, spending >9 hours per day sitting. Prolonged sitting is associated with increased risk for adverse health outcomes in adulthood. Light-intensity physical activity (LIPA) can be integrated into university students’ daily routines to counteract the negative effects of prolonged sitting on cognitive function and musculoskeletal health. OBJECTIVE This protocol describes a trial conducted in Singapore to evaluate the acute (immediate) and short-term delayed effects of two 5-minute LIPA modalities (sit-cycling [S-C] and stand-twisting [S-T]) on neurocognitive and somatic outcomes (prefrontal cortical oxygenation, cognitive performance, subjective sleepiness, and back pain) in physically inactive university students compared to a modality-matched passive control condition. METHODS The study comprised a main study (N=22) and a methodological substudy (n=6, 27.3%). In the substudy, students’ oxygen uptake was measured during 5-minute bouts of S-C and S-T to verify that both modalities meet the operational definition of LIPA. In the main study, physically inactive university students were allocated in a 1:1 ratio to either S-C or S-T (between-participant factor). Each participant completed two laboratory visits within their assigned modality: an experimental LIPA visit and a corresponding modality-matched passive control visit of equal duration (passive sitting for S-C and S-T), enabling within-person intervention-control comparisons. The primary endpoint is the change in bilateral dorsolateral prefrontal cortex (DLPFC) oxygenated hemoglobin (O2Hb) from baseline to immediately after the intervention during cognitive task performance (intervention vs control), measured with functional near-infrared spectroscopy (fNIRS). Secondary outcomes include O2Hb persistence at 20 minutes postintervention, cognitive performance (n-back test and Stroop Color and Word Test [SCWT]), subjective sleepiness, and back pain. RESULTS The study was funded by the Sendai University International Collaborative Research Grant in April 2023, and the trial was registered with ClinicalTrials.gov on November 21, 2024. Participant recruitment and data collection were completed in December 2024. The substudy results showed that both 5-minute S-C and S-T bouts fell within the LIPA range of <3 metabolic equivalents (METs) and could be implemented as brief, standardized LIPA breaks in the main trial. For the main trial, data cleaning and preliminary analyses are ongoing, and the outcomes will be reported in a subsequent outcomes paper (anticipated in late 2026). CONCLUSIONS This protocol provides a prespecified framework to test whether brief 5-minute LIPA bouts may be a practical strategy to interrupt prolonged sitting and acutely improve prefrontal oxygenation and related neurocognitive and somatic outcomes in physically inactive university students. CLINICALTRIAL ClinicalTrials.gov NCT06703424; https://clinicaltrials.gov/study/NCT06703424 INTERNATIONAL REGISTERED REPORT PRR1-10.2196/82510

The COVID-19 pandemic has significantly disrupted the lives of pre-primary school children in Singapore where increased infection rates prompted lockdown measures that altered children’s daily routines. This study aimed to evaluate the impact of the pandemic on the lifestyle behaviours and health quality of 3134 children aged 5 to 6 years across three periods: pre-COVID, COVID-19 lockdown, and COVID-19 endemicity. Data were collected using the Surveillance of Digital Media Habits in Early Childhood Questionnaire (SMALLQ^®) to measure on- and off-screen media habits of children and the Pediatric Quality of Life Inventory (PaedQL) to assess children’s health quality. Adherence to physical activity (PA) guidelines dropped from 32.7% pre-COVID to 27.4% during lockdown but improved to 34.4% in endemicity (p < 0.05). Sleep (SL) adherence followed a similar pattern, decreasing from 33.4% to 27.9% before rising to 40.6% (p < 0.05). Screen time (ST) adherence significantly declined during lockdown (16.7% to 10.8%, p < 0.001). Weak positive correlations with all PaedQL metrics were observed across periods, except during endemicity (p < 0.05). Concerted efforts involving key stakeholders must be made to mitigate the negative effects of the pandemic on children’s lifestyle behaviours and QoL, ensuring they are better prepared for the transition to primary school.