Effects of Exercise on Structural and Functional Changes in the Aging Brain

Abstract

A rapid increase in the elderly population has raised social awareness for maintaining the health of the elderly and initiated intense research in neurodegenerative diseases. Exercise can improve not only cardiovascular and musculoskeletal fitness, but also suppresses the symptoms of depression and anxiety, suggesting a possible role of exercise in the regulation of brain function. Based on a substantial body of literature, here we introduce the effects of exercise on the structural and functional changes in the aging brain, and also discuss the molecular and cellular effects of exercise and motor learning. Studies show that regular exercise in the elderly promotes neurocognitive function, prevents loss of brain tissue, and reduces the risk for neurodegenerative diseases and brain injury. Although the molecular mechanisms, by which exercise regulates brain function, has not been fully understood, recent cell biological and biochemical studies reveal that exercise increases neurogenesis in the hippocampus, elevates the levels of neurotrophins such as BDNF and IGF-1 to promote the survival of newly generated neurons. Exercise also induces angiogenesis in the motor cortex and cerebellum to enhance delivery of glucose and oxygen to neurons. Furthermore, complex motor skill learning increases the number of synapses to improve cognitive and motor function. Taken together, these findings clearly demonstrate that exercise serves as a behavioral intervention to prevent cognitive decline as well as neurodegenerative diseases. Thus long-term regular exercise in parallel with various learning experiences will be required to prepare successful aging. This study will provide fundamental insights into research in neurodegenerative diseases and a better understanding of the exercise effects in brain function.