A study published in the Journal of Affective Disorders has shown that healthy adults who stop regular exercise can experience depressive symptoms as a result, with females displaying a stronger tendency toward depressive symptoms than males.
Of the 6 studies that met the criteria for this systematic review, 2 were randomized controlled trials and 3 others examined immune and neurogenic biological indicators of depressive symptoms. This provided a sample of 152 healthy adults, with 50 females comprising 32.89% of the population. Depressive symptoms increased in both sexes after exercise cessation for periods of 3 days, 1 week, and 2 weeks when compared with baseline; however, cessation affected females significantly more than males.
At week 1 after stopping exercise, participants showed reduced levels of C-reactive protein (CRP) and interleukin 6 (IL6) was reduced at week 2. There were no detectable changes in either tumour necrosis factor (TNF) alpha or brain derived neurotrophic factor.
This systematic review examined 7 databases for studies conducted in English that analyzed the effects of exercise cessation on depressive symptoms. Though researchers also extended their search to major depressive disorder in healthy adults who may or may not have shown depressive symptoms or major depressive disorder symptoms previously, there were no studies that had explored this topic.
Limitations do affect the confidence in these results, including quality concerns such as reporting bias and risks for attrition.
These results suggest that “[ceasing] regular exercise increases [depressive symptoms] in healthy adults, with greater [depressive symptoms] in females than males. Contrary to the cytokine/inflammatory hypothesis of depression, DS were associated with reduced CRP and IL6 and without increased TNF.”
Morgan JA, Olagunju AT, Corrigan F, Baune BT. Does ceasing exercise induce depressive symptoms? A systematic review of experimental trials including immunological and neurogenic markers [published online February 24, 2018]. J Affect Disord. doi: 10.1016/j.jad.2018.02.058.