A meta-analysis of the effects of physical exercise on peripheral levels of a brain-derived neurotrophic factor in the elderly.

Context: The BDNF levels in the elderly are important in several health-related aspects. However, despite the increasing literature on the effects of exercise on BDNF levels, little is known about this issue in the elderly.

Objective: To perform a meta-analysis on the effects of physical exercise of different intensities, duration, and frequency on peripheral BDNF levels in sedentary elderly without cognitive impairment.