IGF1 and Alzheimer disease: The findings of the studies reviewed here suggest that exercise boosts these growth factors, leading to improved overall brain health [32,33]; however, in one recent study similar to that of Lee et al. [21], involving loading characteristics that were nearly 75% of maximal HR, with 25–40 min of exercise for 12 weeks, there appeared to be no significant changes in circulating plasma levels of BDNF, VEGF165, and IGF-1 in adults with Alzheimer’s disease [34].