As of today we know: 1) adults 65 and older are the fastest growing demographic group, reaching 20% of the world population by 2030; and 2) maintaining a sharp mind is a top priority for them. The idea that a healthy mind lives in a healthy body dates back at least 2,000 years, and the benefits of exercise beyond physical health is not a new idea either. The New England Journal of Medicine said this in 1887:
Exercise sustains and improves bodily health by expanding the lungs, quickening the circulation, and promoting growth in muscles and bones. But we know that besides doing all these things, exercise may be made to contribute to brain growth and to the symmetrical development of the mental faculties.