LIVING WELL RUTHAN BRODSKY Special to The Jewish News Above: Fred Kandel works out at the Kahn JCC Health Club. Right: Lincoln Racey gets his exercise on the JCC treadmills. 12/25 1998 L4 Detroit Jewish News Exercise and strength training will beat the stereotype of frail senior citizens. here's no stopping chrono- logical aging; the longer you live. the higher the number. Biological aging, on the other hand — that physical deterioration of the body and mind — can be delayed by exercise. Research validates that an appro- priately designed fitness program, which includes cardiovascular and strengthening components, can slow and even reverse some physiologic decline. It's never too late. Even frail and sedentary older people can regain through exercise some of the function I lost through decades of inactivity Eighty-two-year-old Sarah Levitsky is proof positive. Some time ago, she underwent bypass surgery but now exercises regularly. "Keep exercising and get yourself a< good doctor who cares about you," advises Levitsky, who finds her joints become stiff when she doesn't exer- cise. "That's incentive enough because it's too hard to move around. Exercise is what keeps me going." Her routine includes walking on a treadmill for 10-20 minutes or riding the bike at her cardiologist's rehab center two or three times a week, and walking at a neighboring shopping mall on other days. Massive amounts of research data on aging keep pointing to a healthy older America. During this century, life expectancy in the United States increased from 47 years in 1900 to 76 today By the year 2050, the aver- age American will live about 83 years. That's good news for the millions of baby boomers heading into their 50s. The population of people 65 and older will double by 2040, and those over 85 will come close to tripling by that time. The not-so-good news is that a