A review of recent studies of people 64 and older showed that the benefits of this kind of walking routine increase the longer it is performed, said Roy Shephard, M.D., Ph.D., of the University of Toronto, author of the review.
Past studies by Dr. Shephard suggest that keeping up aerobic fitness is key to delaying the onset of dependency in the elderly.
"There seems good evidence that the conservation of maximal oxygen intake increases the likelihood that the healthy elderly person will retain functional independence,"...
To assess the current state of knowledge on the subject, Dr. Shephard reviewed 30 studies published since 1990.
However, the studies reviewed showed a clear trend toward greater gains in aerobic fitness with a longer training regimen. Average gains, as measured by maximal oxygen intake, were 12.9% in an eight- to 10-week program, 14.1% in a 12- to 18-week program, and 16.9% with 24 to 52 weeks of training.
Studies that used a high-intensity regimen reached gains of 25%, which equals an increase in maximal oxygen intake of 6 mL/kg/min — equivalent to losing about 12 years of biological age.
Dr. Shephard noted that aerobic fitness can also help prevent a variety of conditions that diminish functional capacity, including obesity, diabetes, hypertension, myocardial infarction, stroke, some forms of cancer and osteoporosis.
Exercise also hastens recovery from injuries. Any additional muscle power gained from walking may prevent falls, he said.
These findings are reported online in the April, 2008 British Journal of Sports Medicine.