Inverted-U association between daily steps and WHO-5 in university students: non-linear modeling and robustness...

Area of Science:

• Exercise Science
• Mental Health Research
• Public Health

Background:

• Physical activity is recognized for its mental health benefits, but the precise dose-response relationship is not fully understood.
• The impact of varying physical activity levels on subjective well-being (SWB) requires further investigation, particularly in student populations.

Purpose of the Study:

• To investigate the non-linear association between daily step counts and subjective well-being (SWB) in Chinese university students.
• To identify the step threshold beyond which the benefits for SWB begin to plateau.

Main Methods:

• A cross-sectional study involving 820 university students who wore accelerometers for 7 days to measure daily steps.
• Subjective well-being was assessed using the WHO-5 questionnaire.
• Restricted cubic spline models were employed to analyze the dose-response relationship, adjusting for potential confounders.

Main Results:

• A significant non-linear association was observed between daily steps and SWB (p<0.05).
• SWB increased with step counts up to approximately 8,650 steps/day, after which it plateaued around 19,300 steps/day.
• No tested step count significantly exceeded the minimal clinically important difference compared to 4,000 steps/day.

Conclusions:

• Daily step counts are associated with improved SWB in university students, with benefits leveling off between 8,000-12,000 steps.
• These findings suggest that range-based, progressive step recommendations can support student mental health.
• The study highlights diminishing returns beyond a certain step count, indicating no harm from higher activity levels.