Most people who are severely depressed have a difficult time getting out of bed, let alone getting some exercise. Based on findings from a new meta-analysis, Chinese researchers discovered that sedentary behavior is associated with a 25% increase in developing depression. In other words, if you don’t get much exercise, it could be a significant contributing factor to your feelings of depression.
Meta-Analysis (2014): Sedentary Lifestyle Linked to Depression
A new study published in BMJ Sports Medicine demonstrated that there was a clear link between sedentary lifestyle and depression. The study involved searching throughout a variety of research vaults for studies related to sedentary behavior and depression risk. The journals that the researchers found were archived throughout January 2014. Specifically, researchers pulled studies from PubMed, Web of Knowledge, and Chinese National Knowledge and Wangfang archives to conduct a meta-analysis.
For the meta-analysis, researchers used 13 cross-sectional studies were used with 110,000 total participants and 11 longitudinal studies with over 83,000 participants. The researchers then summarized relative risks (RRs) using a random effects model. The results were not very surprising: sedentary behaviors were found to increase risk of depression by up to 25%.
Of the studies collected, 11 were conducted in Europe, 7 in the United States, 4 in Asia, and 2 in Australia. Individuals who were the least sedentary in general had lower rates of depression. The study detailed more specifics among the sedentary individuals including preferred type of inactivity. Those who preferred to use a computer and/or the Internet while sedentary had a 22% greater depression risk, while those who preferred watching TV had a 13% higher risk.
Relationship Between Sedentary Lifestyle and Depression
Results from this meta-analysis suggest that if you exhibit sedentary behavior, you are more likely to be depressed. It can be assumed that if you get adequate physical exercise on a daily basis, you are less likely to be depressed. Additionally researchers note that promoting physical activity among those who suffer from depression may be beneficial for symptom reduction.
- Sedentary lifestyle could cause depression: Although this study doesn’t necessary prove that a sedentary lifestyle directly causes depression, it does demonstrate a clear link. Based on the variety of mental health benefits that can be obtained through physical activity, it could be assumed that being sedentary may be a root cause of depression for many individuals.
- Exercise can reduce depression: It is already widely known that there are many prominent psychological benefits of exercise, including the reduction of stress and depression. Exercise is known to stimulate neurogenesis (growth of new brain cells), release mood-lifting chemicals called “endorphins,” and release neurotransmitters such as dopamine associated with feelings of pleasure.
- Exercise could cure depression: In cases of severe depression, exercise may not be of much benefit in reducing depressive symptoms. However, for those who are depressed directly as a result of inactivity, exercise may help them feel significantly better. Others who have found exercise to be helpful for their depression even consider it to be a natural cure for depression.
- Exercise improves physical appearance: It’s not rocket science to assume that those who exercise frequently are more likely to be in good shape and have better physiques than those who don’t. Due to the correlation between obesity / being overweight and depression, exercising could help these individuals lose weight. Those who are sedentary are likely to have slower metabolisms and develop obesity, which may result in an unwanted physical appearance and inevitably depression. The improvement in appearance (both objective and subjective) from exercise may contribute to an antidepressant effect in certain individuals. It has already been speculated that improved physical appearance from Botox injections treats depression.
What comes first the sedentary lifestyle or the depression?
It should be noted that the meta-analysis accounted for other factors such as illnesses that may contribute to sedentary behavior. This shows that there is a significant link between sedentary behavior and depression. However, it remains unknown as to whether: sedentary behavior leads to depression, depression leads to sedentary behavior, or whether it is a result of a combination of both.
In any regard, since the two factors are linked, it is suggested that increasing physical activity can be beneficial for those who are depressed. Keep in mind other things that can lead a person to engage in sedentary behavior besides feeling depressed. In many cases there are complex interactions between our brain, environment, and/or any pharmacological drugs (e.g. antidepressants) that could make us sedentary and/or depressed.
Causes of sedentary behavior in depression
It should be noted that there are many potential causes of sedentary behavior including: environmental factors, social influences, your brain, as well as medications (i.e. antidepressant side effects).
- Environmental factors: Many environmental factors such as a busy schedule or relationships can distract a person from getting adequate exercise. It is especially difficult to get proper exercise if a person hangs around others who are sedentary and don’t make exercise a priority. Many people simply don’t make exercise a priority because they view other aspects of life as being more important.
- Dorsal medial habenula: This region in the brain was recently found to contribute significantly to exercise motivation. Those who were highly motivated to exercise had more activity in this particular area of the brain. Those who have deficits in the dorsal medial habenula are thought to engage in more sedentary behavior, and thus could end up becoming overweight and possibly depressed. The dorsal medial habenula influences motivation to exercise, thus contributing to feelings of laziness.
- Antidepressants: It is already known that antidepressants and weight gain are closely linked. Most SSRIs do this by increasing appetite, slowing metabolism, and inhibiting the reuptake of the neurotransmitter serotonin. Treatment with antidepressants, particularly SSRIs can make some people significantly more lethargic and tired than usual – making it nearly impossible to get adequate exercise.
Although there is not a causal relationship between sedentary behavior and depression, there is a clear link. There is also mounting evidence suggesting that moderate physical activity can help reduce depressive symptoms. If you suffer from depression, one of the best things you can do for yourself is get adequate exercise.
Exercise is natural, effective, and best of all – it’s free. Forcing yourself to go to the gym or get more exercise may be uncomfortable for those who are depressed, but it may be just what you need to help get your symptoms under control.