We recently published a study in the International Journal of Mental Health and Addiction, “Physical Activity Moderates the Relationship Between Frequency of Past 90-Day Cannabis Use on Psychological Distress Among a National Sample of College Students”. This study sheds light on the interplay between cannabis use, physical activity (PA), and psychological distress (PD) in college students. We used data from over 157,000 students collected from the American College Health Association’s National College Health Assessment III (2019–2023), which includes responses from 127 universities across the U.S.

The aim of the study was to explore whether physical activity could act as a buffer against the psychological distress often associated with cannabis use. Cannabis use has been linked to increased PD, while regular physical activity has consistently been shown to reduce stress and improve mental health. Given the high rates of both cannabis use and psychological distress among college students, this study sought to determine if higher levels of physical activity could mitigate the mental health challenges linked to frequent cannabis use.

Participants were surveyed on their frequency of cannabis use over the past 90 days, which was categorized into three groups: “never,” “once-monthly,” and “weekly-daily.” Psychological distress was measured using the Kessler 6 Non-Specific Psychological Distress Scale (K6), a widely used tool that assesses symptoms like nervousness, hopelessness, and sadness. In addition, physical activity was assessed based on time spent on moderate or vigorous activities, as well as the number of days per week dedicated to strength training.

Key Findings

We found that higher frequencies of cannabis use were linked to increased psychological distress. However, students who engaged in more physical activity consistently reported lower levels of psychological distress, even when cannabis use was frequent. This suggests that physical activity may serve as a protective factor, helping to reduce the negative mental health effects of cannabis use.

More specifically, those who reported higher levels of physical activity (both moderate and vigorous) were less likely to experience the psychological distress typically associated with cannabis use, compared to those with lower levels of activity. This protective effect was particularly noticeable in students who used cannabis once monthly.

The Role of Cluster Analysis

To better understand how physical activity levels interact with cannabis use and psychological distress, we employed a Two-Step Cluster Analysis. This statistical method grouped participants into two clusters based on their physical activity patterns: a “High PA” group and a “Low PA” group. The High PA cluster included participants who engaged in significantly more moderate and vigorous exercise and strength training, while the Low PA cluster consisted of those who reported less activity.

The results showed that individuals in the Low PA cluster had higher psychological distress scores across all levels of cannabis use, while those in the High PA cluster exhibited lower psychological distress scores. This cluster analysis provided a clearer picture of how physical activity moderates the relationship between cannabis use and psychological distress, with the High PA cluster consistently demonstrating lower distress levels.

Implications

The findings suggest that promoting physical activity could be an effective public health strategy to reduce psychological distress, particularly among cannabis users. As cannabis legalization becomes more widespread, understanding how lifestyle factors like physical activity can buffer against mental health challenges is crucial.

By incorporating exercise into harm-reduction strategies, universities and public health officials could help students manage both their cannabis use and mental health more effectively. Future research should explore the long-term effects of physical activity on cannabis users, as well as investigate other factors, such as the role of social support, that might further influence the relationship between cannabis use and mental health.