Many studies have provided evidence on the link between exercise and good mental health. Those studies had suggested that people who exercise more are less likely to experience mental illnesses.
However, those studies rely on people self-reporting their activity levels, which can be less reliable than objective physical fitness measures.
A new study by the University College London, which used objective physical fitness measures, has suggested that people with low aerobic and muscular fitness are nearly twice as likely to experience depression. There is a 60% greater chance of anxiety as well.
The study included 152,978 members aged 40 to 69 of the UK Biobank study. At the beginning of the study, their baseline aerobic fitness was tested using a stationary bike with increasing resistance. In contrast, their muscular fitness was estimated with a grip strength test. They also completed a questionnaire gauging depression and anxiety symptoms.
After seven years, when tested again for depression and anxiety symptoms, scientists found that high aerobic and muscular fitness at the start of the study was associated with better mental health seven years later.
People with the lowest combined aerobic and muscular fitness had 98% higher odds of depression, 60% higher odds of anxiety, and 81% higher odds of having either one of the common mental health disorders than those with high levels of overall fitness.
Senior author Dr. Joseph Hayes (UCL Psychiatry and Camden and Islington NHS Foundation Trust) said: “Our findings suggest that encouraging people to exercise more could have extensive public health benefits, improving not only our physical health but our mental health too. Improving fitness through a combination of cardio exercise and strength and resistance training appears to be more beneficial than just focusing on aerobic or muscular fitness.”
Lead author, Ph.D. student Aaron Kandola (UCL Psychiatry), said, “Reports that people are not as active as they used to be are worrying, and even more so now that global lockdowns have closed gyms and limited how much time people are spending out of the house. Physical activity is an important part of our lives and can play a crucial role in preventing mental health disorders.”
“Other studies have found that just a few weeks of regular intensive exercise can make substantial improvements aerobic and muscular fitness, so we are hopeful that it may not take much time to make a big difference to your risk of mental illness.”
- Aaron A. Kandola et al., Individual and combined associations between cardiorespiratory fitness and grip strength with common mental disorders: a prospective cohort study in the UK Biobank, BMC Medicine (2020). DOI: 10.1186/s12916-020-01782-9