- Regular exercise and staying in good shape has the potential to lower depression risk and keep anxiety at bay.
- People with better cardiorespiratory fitness buy fewer anxiolytics and antidepressants, a linkage study found.
- The link between being in good shape and buying fewer mental health medications is correlative, not causative.
- Exercise isn't a panacea or a substitute for doctor-prescribed medications that treat clinical disorders.
In 2019, an international team of researchers led by Linds Ernstsen of the Norwegian University of Science and Technology published a study that identified a correlation between higher levels of cardiorespiratory fitness (CRF) and lower risk of depression.
For this cross-sectional study, data from 26,615 people who participated in Norway's Nord-Trøndelag Health Study (HUNT) showed that being in good shape was correlated with lower odds of depression depending on someone's level of fitness—indexed as low, medium, or high CRF.
For example, Ernstsen and colleagues found that among those who participated in the HUNT study, people with "medium" levels of cardiorespiratory fitness had 21% lower odds of depression. Those with "high" CRF were 26% less likely to experience depressive symptoms than those with "low" CRF.
This 2019 cross-sectional analysis of HUNT data didn't unearth a link between higher levels of fitness and less anxiety but her team's latest (2023) research suggests that higher CRF is linked to buying fewer anxiolytics (anti-anxiety drugs).
Higher CRF Is Linked to Fewer Anxiolytic and Antidepressant Purchases
A follow-up study (Havnen et al., 2023) led by Ernstsen examines how being in good shape (as indexed by CRF) might affect someone's risk for experiencing anxiety and depression based on prescription purchase rates for anxiolytics such as benzodiazepines and antidepressants such as selective serotonin reuptake inhibitors (SSRIs). The peer-reviewed findings of this linkage study were recently published in the Journal of Affective Disorders.
Based on a linkage comparison between the Norwegian Prescription Database and HUNT participants' cardiorespiratory fitness levels, Ernstsen and coauthors found that, on average, increasing CRF by one metabolic equivalent of task (MET) was associated with a 4% lower rate of filling prescriptions for antidepressant or anxiolytic medication.
On a continuum, MET-measured improvements in cardiorespiratory fitness were associated with purchasing fewer antidepressants and anxiolytics. Based on these findings, Ernstsen and coauthors speculate that increasing CRF may protect against the need for anti-anxiety or antidepressant medications.
"We [found] that people who are in better shape fill fewer prescriptions for anxiety and depression medications. Being in better physical shape appears to reduce the need for anxiolytic drugs and antidepressants," senior author Linda Ernstsen said in an August 2023 news release about her team's latest findings.
Correlation Doesn't Imply Causation
Because correlation does not imply causation, it's important to note that all of the findings from this type of research are correlative. It's impossible to know with 100% certainty if doing cardio and being physically fit reduces depressive symptoms and lowers anxiety or if people who are less depressed and less anxious tend to exercise more and stay fit.
Another limitation of this study is that the researchers based their findings on sales information from the Norwegian Prescription Database and could only establish that someone had purchased anxiolytics or antidepressants. However, they couldn't confirm that someone had taken the prescribed medication. As the authors note, "Only information about medication purchase and not actual use was available."
Physical Fitness May Lower Your Odds of Anxiety and Depression but Isn't a Cure-All
Mountains of evidence-based research show a correlation between regular exercise, improved fitness, and fewer depressive symptoms. Accumulating science-backed evidence also indicates that physical activity helps keep anxiety at bay. Additionally, anecdotal evidence based on people's lived experience suggests that staying active and getting in shape lowers one's risk of getting depressed and reduces chronic stress.
That said, exercise is not a panacea. For many people with clinical depression, major depressive disorder, or crippling generalized anxiety disorder, doing cardio and getting in shape isn't a magic bullet that will eradicate mental health issues. Being fit may lower the odds of getting depressed or experiencing acute anxiety; however, working out shouldn't be viewed as a substitute for taking doctor-prescribed anxiolytics or antidepressants.
Disclaimer: This blog post is not intended as medical advice. If you take any prescription medication, always speak to your prescribing doctor before altering your dosage or going off your meds.
Audun Havnen, Ekaterina Zotcheva, Ottar Bjerkeset, Xuemei Sui, Linda Ernstsen. "Cardiorespiratory Fitness and Incident Use of Anxiolytics and Antidepressants in Adults. A Linkage Study Between HUNT and the Norwegian Prescription Database." Journal of Affective Disorders (First published online: July 10, 2023) DOI: 10.1016/j.jad.2023.07.029
Rajesh Shigdel, Brendon Stubbs, Xuemei Sui, Linda Ernstsen. "Cross-Sectional and Longitudinal Association of Non-exercise Estimated Cardiorespiratory Fitness With Depression and Anxiety in the General Population: The HUNT Study." Journal of Affective Disorders (First published: April 11, 2019) DOI: 10.1016/j.jad.2019.04.016