An estimated 60% of U.S. adults fail to participate in regular
physical activity, and nearly one in four arenít active at
all -- despite
the established associations between exercise and the risk
of coronary heart disease (CHD), cancer, and numerous other
If time and/or energy constraints keep you from exercising,
take note of the results of the Harvard Alumni Health Study.
More than 7,000 healthy men reported the number of city blocks
and flights of stairs they walked each day, and their weekly
participation in recreational activities (frequency and duration).
Follow-up questionnaires were used to determine how many men
had developed CHD or related heart conditions.
Exercise duration had little or no effect on CHD risk, after
adjusting for total energy and other variables. Specifically,
longer sessions of exercise were no more effective than shorter
sessions in reducing risk, when total energy expenditure remained
constant. So get off that couch and start exercising! If multiple
short exercise sessions are as efficient as a single long
session, youíve got no excuse for staying inactive.
Ask your doctor to help outline a fitness regimen suitable
to your needs.
Lee I-M, Sesso HD, Paffenbarger Jr. RS. Physical activity
and coronary heart disease risk in men: does the duration
of exercise episodes predict risk? Circulation 2000:
Vol. 102, pp981-96.