The human brain can show remarkable experience-induced plasticity under conditions such as aging and pathology. However, the mapping of changes provided by many imaging approaches often lacks specificity with respect to biological tissue properties, which is relevant for treatment optimization and the evaluation of health-promoting lifestyle factors. Training-induced structural changes in cortical and subcortical gray matter likely reflect a mixture of various microstructural processes. In order to non-invasively map these different microstructural contributions, we used quantitative magnetic resonance imaging (qMRI) to measure clinically-relevant brain tissue property changes (such as iron, myelin, and water) in response to 4 weeks of motor balance training in 26 healthy young adults. Training resulted in a regionally-specific decrease in myelin-related magnetization transfer saturation (MT