In individuals with major depressive disorder (MDD), researchers found no evidence that resting plasma concentrations of peripheral brain-derived neurotrophic factor (BDNF) increase after aerobic exercise, according to meta-analysis results published in the Journal of Psychiatric Research.
Researchers analyzed 6 previous studies and 176 participants with MDD (mean age 42.9±6.6, 67% female, mean body mass index 28.3±2.5) were included in the meta-analysis. The mean aerobic exercise intervention included 47.2±7.2 (42.5-60) minutes per assembly at 57.5%±10.3% (50% to 70%) of maximal oxygen uptake, 2.6±0.89 (1-3) times per week for 7.5±3.9 (3-12) weeks. Among the participants, 75% were taking one or more antidepressants during the aerobic exercise intervention.
Of the 6 included studies, researchers noted that resting concentrations of plasma BDNF did not significantly increase following the exercise intervention (SMD 0.43, 95% CI, -0.06 to 0.92, P =.09)
Researchers concluded that “Results from this meta-analysis did not reveal an increase in resting concentrations of BDNF in the blood of individuals with MDD after a chronic aerobic exercise intervention.” They pointed out the lack of studies in this area, making it difficult to reach a strong conclusion and stressed the need for larger studies in the future.
Dinoff A, Herrmann N, Swardfager W, Gallagher D, Lanctôt KL. The effect of exercise on resting concentrations of peripheral brain-derived neurotrophic factor (BDNF) in major depressive disorder: A meta-analysis. J Psychiatr Res. 2018;105:123-131.