Department of Medicine, Division of Cardiology, Johns Hopkins Bayview Medical Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224, USA
Address for correspondence: Kerry J. Stewart, Ed.D,, Professor of Medicine, Johns Hopkins Bayview Medical Center, 4940 Eastern Avenue, Baltimore, MD 21224. Voice: 410-550-0870; fax: 410-550-7727. kstewart{at}jhmi.edu
Most human beings experience peak physical performance in their
late teens and begin a slow decline in their early 20s, whose
course is greatly affected by the activity levels undertaken
by individuals in the years that follow. Many studies provide
evidence that in developed nations such as the U.S., a sedentary
lifestyle contributes significantly to development of the major
risk factors for age-related disease, prominent among them obesity,
diabetes, and hypertension. Conversely, numerous studies document
the benefits of physical activity, and in particular structured
exercise programs, not only for reducing disease risk and improving
physical performance, but also for enhancing substantially the
quality of daily life. Aerobic and resistance training have
complementary benefits, and can be undertaken at almost any
age and physical condition, given appropriate medical clearance
and supervision as warranted.
