TOPLINE

Lower levels of physical exercise were associated with a higher risk for common mental disorders (CMDs) among students pursuing higher education, a Norwegian prospective cohort study found. Frequent exercise, adhering to weekly activity recommendations, and increased total weekly exercise volume were associated with a reduced risk for CMDs.

METHODOLOGY

• Researchers analysed data from SHoT2022, a national survey of Norwegian higher education students aged 18-35 years, with baseline data collected from 53,362 participants between February and April 2022.
• Physical exercise frequency, intensity, and duration and total weekly exercise hours were assessed at baseline using a prevalidated three-item questionnaire based on the World Health Organization (WHO) guidelines of at least 150 min/wk of moderate-to-vigorous physical activity (MVPA). 
• CMD, defined as a major depressive episode or generalised anxiety disorder during the past 30 days or 12 months, was assessed 1 year later using the self-administered Composite International Diagnostic Interview (version 5.0) in 10,460 participants.
• Risk ratios (RRs) were estimated for subsequent CMDs across exercise frequency, intensity, and duration and weekly exercise hours, stratified by sex and age groups (18-24 and 25-35 years).
• Models were sequentially adjusted for age, immigrant background, parental education, student parental responsibility, and relationship and accommodation status (model 2) and additionally adjusted for baseline psychological distress measured using the 25-item Hopkins Symptom Checklist (model 3).

TAKEAWAY

• Students who seldom or never exercised had a significantly higher risk for CMDs than those who exercised daily (women: adjusted RR [aRR], 1.15; 95% CI, 1.04-1.28; men: aRR, 1.33; 95% CI, 1.06-1.65).
• Low exercise intensity predicted a higher risk for CMDs in women (aRR, 1.31; 95% CI, 1.13-1.52), and short exercise durations of less than 15 minutes (aRR, 1.67; 95% CI, 1.17-2.39) and 15-29 minutes (aRR, 1.22; 95% CI, 1.01-1.48) predicted a higher risk in men. 
• Students who exercised below WHO MVPA recommendations had an elevated risk for CMDs (women: aRR, 1.10; 95% CI, 1.03-1.17; men: aRR, 1.17; 95% CI, 1.01-1.34). 
• Weekly exercise hours showed an inverse curvilinear association with CMDs among women (plateauing at approximately 5-6 h/wk; P < .05 for non-linearity); however, among men, the risk continued to decline across higher weekly exercise volumes, with no significant evidence of non-linearity. 

IN PRACTICE

"[The study] findings underscore the importance of regular and sustained physical exercise as a potential target for student mental health promotion. Promoting consistent and attainable exercise routines, rather than emphasising high intensity or extreme volumes, may represent a pragmatic component of broader student mental health promotion efforts," the authors wrote.

SOURCE

The study was led by Michael Grasdalsmoen, Western Norway University of Applied Sciences, Bergen, Norway. It was published online on August 19, 2026, in PLoS One.

LIMITATIONS

The study was limited by self-reported physical exercise measurements; the observational prospective design with potential reverse causation; modest baseline response rates (35.1%) with follow-up attrition; the absence of baseline diagnostic assessment for CMDs; potential residual confounding from unmeasured factors such as medication and substance use; web-based self-administration of diagnostic tools rather than clinical interviews; and the omission of contextual exercise characteristics such as activity type, social context, and enjoyment.

DISCLOSURES

The SHoT study received financial support from the Norwegian Ministry of Education and Research and the Norwegian Ministry of Health and Care Services. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.