BDNF and major depressive disorder: Although it has been proven that exercise in MDD patients reduced depressive symptoms (Herring et al. 2012; Ota and Duman 2013; Schuch et al. 2016), neuroplasticity per se has not yet been monitored in patients in these conditions, due to the limitations mentioned in section “Neuroplasticity changes in MDD.” However, a meta-analysis has suggested that acute aerobic, but not strength exercise, increases basal peripheral BDNF concentrations, although this effect was only transient (Knaepen et al. 2010).