If exercise helps fight off depression as we’ve heard time and time again of late, it would make sense that stopping to exercise would then bring on depression or depressive symptoms in those with a prior history of depression, wouldn’t it?
Yes and no, according to a new study in the Journal of Affective Disorders which found that depressive symptoms arise two weeks from when a person stops exercising.
But here's the kicker. What’s baffling researchers is that acquiring depressive symptoms post exercise could actually be a distinct subtype of depression.
That’s because, right now, the prevailing theory is that inflammation in the body causes depression. But in this study, which went over previous studies on exercise and depression, people who stopped exercising who developed depressive symptoms did not have an increase in inflammation in the body.
Depression is a term thrown out a lot these days but what is depression really? According to the Diagnostic and Statistical Manual of Mental Disorders, the clinical term is Major Depressive Disorder (MDD).
The symptoms of MDD include a loss of pleasure in daily activities, biological symptoms of appetite, weight and sleep changes, reduced libido, cognitive symptoms such as poor attention, concentration and memory, and somatic symptoms that can include fatigue and an increase in the sensation of pain. In order to qualify for a diagnosis of MDD, these symptoms need to persist for at least two weeks.
Unfortunately, medication for MDD is only 50-60% effective so researchers are always looking at alternative types of therapy including exercise and have found that it can reduce and prevent depressive symptoms as well as MDD. Doctors have even started prescribing exercise in order to get their patients to take it seriously.
The American College of Sports Medicine defines exercise as “a subclass of physical activity that is planned, structured, and repetitive bodily movement done to improve or maintain one or more components of physical fitness.”
It has been shown that exercising three times a week for at least eight weeks can improve MDD significantly. People who exercise have a 45% lower chance of having depressive symptoms that those who live a sedentary lifestyle.
There are different types of exercise: aerobic, strength training, and flexibility. Studies have shown that any type of exercise works in reducing depressive symptoms, however, a combination of different types of exercise is more efficacious.
How does exercise reduce depressive symptoms? Biologically and technically speaking, exercise improves monoaminergic function (the function of neurotransmitters), neurogenesis, and immunity. When someone exercises, their muscles are increasing the production of interleukin which prevents inflammation in the body.
In the current study, researchers also found that in those that stopped exercising, the incidence of depressive symptoms was higher in females than in males. Researchers are interested in looking at the biological causes of this discrepancy.
Interestingly, previous studies have found that women low in the amino acid, tryptophan, suffer from depressive symptoms, while men low in tryptophan do not. Researchers in the current study theorize that women who have stopped exercising may have disrupted tryptophan levels but more studies are required to test this theory further.
The cessation of exercise has also caused an increase of anxiety symptoms as well as depressive symptoms. Despite the interesting findings, the authors of the study admit they weren’t happy with the quality of studies they examined and encourage more trials on the subject that include more female participants.
Julie A. Morgan, Andrew T. Olagunju, Frances Corrigan, Bernhard T. Baune, (February 2018), Journal of Affective Disorders, Does ceasing exercise induce depressive symptoms? A systematic review of experimental trials including immunological and neurogenic markers, https://www.ncbi.nlm.nih.gov/pubmed/29529552
Patricia Tomasi is a mom, maternal mental health advocate, journalist, and speaker. She writes regularly for the Huffington Post Canada, focusing primarily on maternal mental health after suffering from severe postpartum anxiety twice. You can find her Huffington Post biography here. Patricia is also a Patient Expert Advisor for the North American-based, Maternal Mental Health Research Collective and is the founder of the online peer support group - Facebook Postpartum Depression & Anxiety Support Group - with over 1500 members worldwide. Blog: www.patriciatomasiblog.wordpress.com