Multicomponent physical exercise is the most recommended type of physical intervention in older adults. Experimental data suggest the relevance of the muscle-brain axis and the relationship between muscle contraction and release of brain-derived neurotrophic factor, however, the impact of this relationship on cognition remains unclear, especially in people with diagnosis of cognitive impairment. This study assesses the effect of multicomponent physical exercise on global cognition in people with mild cognitive impairment or dementia.