I don t exercise enough, like many of you. (Far too many, in fact: Of Americans 50 and older, 46 percent don t exercise at all, according to a report in the journal Preventing Chronic Disease.) Sure, we realize that a sedentary lifestyle, especially when coupled with bad eating habits, adds extra pounds. And that being overweight can lead to disabling diseases such as cardiovascular problems, diabetes, osteoporosis and even cancer. But for many years, Americans could take comfort in the fact that the costs of neglecting our health were outweighed by the benefits of improving medical technology.

But recently, the number of seniors developing disabling health problems has begun to rise. And as more individuals tragically lose their personal freedom to illness, more families will have to grapple with crushing long-term-care bills. So will the federal budget. Already, about two-thirds of Medicaid spending and more than one-third of Medicare spending are associated with disability. If even more seniors get sick, those costs will soar.

Two recent studies bear the gloomy but important details. According to research published in The Journals of Gerontology in December, the proportion of people older than 65 and living on their own who had trouble with basic daily activities such as dressing, bathing or moving around their homes, jumped 9 percent from 2000 to 2005 (the latest year for which data was available). And according to a paper published in the American Journal of Public Health in January, folks 60 and up showed significant increases in nearly every kind of disability when comparing the period 1999 to 2004 with 1988 to 1994. We see these data as extremely worrisome, says Teresa Seeman, professor of medicine and epidemiology at UCLA and coauthor of the latter study.

Seeman s research found disability rates jumped most for 60- to 69-year-olds, who entered adulthood in the 1960s, when obesity first started becoming a serious health problem in the U.S. The boomers coming up behind them have spent even more of their lives under conditions that prompt people to gain too much weight which could drive disability rates even higher.

That s the bad news, and it s pretty bad. The good news is that there are steps we can take to prevent disabling illness, or at least to minimize its financial impact. The first piece of advice experts give, of course, is to get in shape. Ride a bike, find a walking buddy, get a dog; the long-term financial benefits will be huge.

Further, you may not realize just how much Medicare has expanded its emphasis on prevention since 2005. Medicare now fully covers diabetes screenings up to twice a year and one cholesterol test every five years. And it will pay for 80 to 100 percent of the cost of bone-mass tests, colorectal exams, glaucoma screenings, mammograms and Pap tests. If you re 65 or older, take advantage of these offerings, and if you re younger, use this list as a road map for checkups with your doctor.

Beyond these standard tests, you should stay alert for signs of illnesses that can be crippling but are underdiagnosed. These could fill a book, but here we ll look at four important examples. Sarcopenia is a loss of muscle mass, which can weaken you and restrict your mobility as you age. Scientists and most seniors have paid far less attention to it than osteoporosis (the loss of bone mass). In fact, there is no approved definition of what sarcopenia is, and therefore, there are no standards for it like there are for, say, blood pressure and hypertension, says Christy Carter, professor of geriatrics at the University of Florida. But muscle loss is one of the leading reasons people end up in nursing homes, and sarcopenia might affect 40 percent of Americans age 80 and older. It s crucial to get your muscles tested.

Generalized anxiety disorder is chronic, uncontrollable worrying. And it may be more than twice as prevalent among seniors as depression, afflicting up to 7 percent of people older than 60, according to research by the University of Pittsburgh School of Medicine. Of course, it s common to be concerned about health, money and family issues as you age. But if you find yourself fretting constantly about everyday activities for more than six months, tell your doctor.

One medical journal has called kidney failure a silent epidemic among seniors because of how often renal trouble goes unrecognized. Indeed, a study published in 2006 in the Annals of Internal Medicine found that 22 percent of research participants 65 or older had chronic kidney disease, while another 39 percent had preclinical kidney disease or the early stages of renal malfunction. At whatever stage, kidney disease puts you at greater risk for cardiovascular problems and death. Especially if you re being treated for other health problems, check with your doctor that you re not overloading your kidneys.
And contrary to myth, sleep problems aren t a natural consequence of aging. Instead, if you can t sleep well for seven hours a night, it may be a wake-up call, if you will, that you have arthritis, cardiovascular trouble or other problems. For example, a 2003 study by the Mayo Clinic of patients who had impaired heart function but who had not yet developed full-blown heart failure found that 66 percent suffered from sleep apnea. Such problems tend to grow worse over time, because sleeplessness in turn interferes with your body s attempts to heal illnesses naturally.

But if you re diagnosed with a chronic disease such as arthritis or diabetes, don t despair. Projects around the country are helping patients navigate illnesses and stave off disability like the Chronic Disease Self-Management Program, developed by the federal Agency for Healthcare Research and Quality. The program, offered at churches, libraries and senior centers, teaches patients how to eat, exercise and use medication properly; handle the emotions of chronic illness, such as fatigue and frustration; and evaluate new treatments. And it works: Participants report improved symptoms and energy and spend less time and money on doctor, hospital and emergency-room visits, according to evaluative research. For classes in your area, see http://patienteducation.stanford.edu/organ/cdsites.html.

Remember the old saying An ounce of prevention is worth a pound of cure ? With disabilities, it s more like a ton.