FNDC5 and stroke disorder: Post-stroke high-intensity interval training reduced ischemic brain damage and upregulated pTrkB (a major cascade of BDNF actions) and FNDC5 expression in the cortex of rats (Pin-Barre et al., 2021), which underscores its role in neuronal survival, hippocampal neurogenesis, synaptic plasticity, and functional recovery (Liu and Nusslock, 2018; Cohan et al., 2019; Luo et al., 2019).