Physical Activity, Depression and Inflammation
Physical activity is commonly prescribed for the prevention and treatment of depression. While an abundance of research has consistently outlined the improvements that physical activity has on psychological symptoms, the specifics around what facilitates these improvements on a cellular level remain unanswered and continues to be a focal point in ongoing research.
One area that continues to receive a lot attention is the often-associated high levels of inflammation in those diagnosed with depression, which is hypothesized to influence both psychological symptoms and cardiometabolic health. Furthermore, physical activity has been found to reduce levels of inflammation in healthy populations and those with poor cardiometabolic health, however the effectiveness in those with depression is not fully understood.
A group of researchers recently conducted a study consisting of 8,048 adults, investigating the association between levels of physical activity, depression symptoms and blood levels of low-grade inflammation (C-reactive protein). Their findings suggested that both depressive symptoms and physical inactivity are associated with increased levels of inflammation. Additionally, physical activity explained approximately 13% of the association between depression and inflammation levels.
In summary, this study has supported one of the many theories that aim to explain how exercise can be attributed to improvements in psychological and physical heath in those with depression. However, it is important to note that inflammation is only one area that was focused on within this study and we know through other research that over 8,000 molecular changes occur during exercise, which are likely to contribute to the overall benefits of physical activity.
André O. Werneck et al. 2020. Does physical activity influence the association between depressive symptoms and low-grade inflammation in adults? A study of 8,048 adults. Physiology & Behavior.