Exercise Intensity and Brain Neuroplasticity with Special Emphasis on Lactate-BDNF Molecular Pathways: A PRISMA-Compliant Focused Systematic Review

Abstract

Context: Exercise training exerts differential effects on brain neuroplasticity depending on its type and intensity. This review aimed to evaluate recent studies examining the effect of exercise intensity on neuroplasticity-related outcomes. Evidence Acquisition: A comprehensive literature search was conducted across international databases, including PubMed, ScienceDirect, and Scopus, and was supplemented by manual searching of reference lists. Keywords included “Exercise,” “Neuroplasticity,” “BDNF,” and “Lactate” in various combinations. Studies published between 2004 and 2024 were considered. Of 120 initially identified articles, 8 met the inclusion criteria. Results: Exercise intensity modulates neuroplasticity through distinct molecular pathways, including the upregulation of neurotrophic factors (e.g., BDNF, VEGF, IGF-1) and increases in circulating lactate. Lactate, a metabolite closely associated with exercise intensity, appears to act not only as an energy substrate for the brain but also as a signaling molecule that enhances neurotrophic factor expression and activates pathways involved in synaptic plasticity and neuroprotection. Collectively, these adaptations promote enhanced brain plasticity and cognitive function.