First, Stein and colleagues showed small-to-moderate effects of 12 weeks’ AEx compared to usual-care control on resting plasma BDNF (SMD = 0.31, 95%CI [−0.45, 1.05]) and IGF-1 levels (SMD = −0.61, 95%CI [−1.29, 0.10]) in 34 participants with mild-to-moderate AD dementia [26]. Here, BDNF is linked to Alzheimer disease.