They're a crafty lot, these University of Pittsburgh researchers who take pride and pleasure in their ability to knock people down -- and the older the victim, the better.

Tony Tye, Post-Gazette Carol Lydon is participating in a study at the Human Movement and Balance Laboratory at Pitt that has her harnessed to prevent injury while researchers study her motion as she slips or tumbles on a slippery substance smeared on the floor. Click photo for larger image. Related article: Projects will educate about fall prevention

True, they're not overtly sadistic about it as they plot Carol Lydon's tumble in a Benedum Hall laboratory. The graduate students' mischievous smiles are nonetheless evident as they spread soapy, slippery liquid on the floor the grandmother will soon cross. She faces a wall oblivious, wearing headphones that play classical music to drown out their conversation.

The scheming is in the interest of science, not elder abuse. The researchers in the Human Movement and Balance Laboratory make people fall in a safe environment, hoping it will someday help others avoid falling to the sound of bone fractures.

"I want you to walk as if you're going somewhere," laboratory manager April Chambers tells Lydon, 64, who strides face-forward across the room in a spandex outfit covered with 79 sensors that resemble Ping Pong balls.

Unlike the prior 10 times she walked just fine on dry tile, she slides now on the glycerol. It's not a big stumble, just a stutter, recorded by video cameras and computer software that measured the pressure of her steps. The healthy Lydon probably didn't even need the harness to which she was attached, which prevents actual tumbles to the floor among research subjects.

"We would call that a slip and recovery," said Rakie Cham, an assistant professor of bioengineering heading a National Institute for Occupational Safety and Health study of how strength and flexibility -- or actually, the lack thereof -- factor into falls. She works with Mark Redfern, a Pitt bioengineering professor who has been studying balance difficulties.

The Pitt research is among a range of studies increasing in scope around the country to address falls and how to prevent them, or how to reduce the likelihood that the "fallee" will be seriously injured when they occur. The problem is attracting more attention because of the growth of the elderly population and the high cost of medical care for injuries that are often avoidable.

The U.S. Centers for Disease Control and Prevention and other government agencies report that more than half of the fractures resulting in hospitalization occur among people 65 and older. The risks increase steadily as people age, with bone and muscle strength declining naturally. Older adults also react more slowly to unexpected stumbles, or have more difficulty with multiple tasks that can affect concentration.

Hip fractures among the elderly number some 338,000 annually, typically requiring hospitalization for a week, with an average cost of about $20,500 for treatment. A fourth of those turn into long-term institutionalization, and risks of mortality and isolation increase even for those who aren't forced into nursing homes.

"It touches so many families, and if we could become more proactive, I think that is to the advantage of the entire community," said Mary Esther Van Shura, assistant director of Pittsburgh's Department of Parks and Recreation, who remembers her grandmother falling at home, breaking a hip and entering a nursing home permanently.

The department, for which she oversees senior centers, hopes to collaborate with Mercy Hospital next year on a falls prevention program for center attendees. Foundation or corporate funding is being sought for that.

Leg and arm strength

James Ashton-Miller, a University of Michigan research professor in mechanical engineering, said anyone with the ability to exercise both their lower and upper body should be doing it to reduce falls and injuries. If people walk a lot, it puts them in the practice of taking quick steps needed to rebalance themselves when stumbling unexpectedly. If they improve arm strength, it can be valuable in using hands and wrists to cushion blows from falling sideways or forward.

A wrist injury is preferable to those of the hips or head, he noted. But if a person has "toothpick arms," from lack of any regular use, the instinctive, defensive reaction of thrusting hands to the ground first will be of little value.

"It's use it or lose it," Ashton-Miller said.

Bone density plays a part in rates that show women over 65 are three times as likely as men their age to experience fractures, which isn't the case when they're younger. Women more commonly have the brittle bone disease of osteoporosis than men, and the CDC reports that women's rate of fall-related injuries increases rapidly after age 55. Women experience 80 percent of hip fractures.

Dr. Kelly Krohn, a Mercy Hospital rheumatologist, said an aerobics and stretching program that the hospital and Highmark Blue Cross Blue Shield sponsor at a Bethel Park health club has proven effective in improving strength and balance among a group of older, suburban women. It presumably reduces their fall risk, said Krohn, a researcher of osteoporosis who has been discussing with Van Shura how to extend such preventive programs to the city senior centers.

Even without such organized efforts, Krohn said, many people could avoid falls just by taking vitamin D supplements. Pittsburgh's lack of sunshine most of the year reduces the population's natural levels of vitamin D, which Krohn described as an important resource for seniors trying to maintain strength and a steady gait.

"When you're vitamin D-deficient, you get weak, have trouble getting up from your chair, you're wobbly on your feet, and will fall easier," he said.

Even though there's a lot of research about falls and ways to prevent them, not enough of that information is available to the public, said Thurmon Lockhart, director of Virginia Tech's Locomotion Research Laboratory.

Part of the problem, he said, stems from researchers' failure to collaborate nationally on data that separately examine the physical, psychological, environmental and medical factors related to falls. He knocks down people in the laboratory, as the Pitt researchers do, trying to find out which muscles are activated in recovery from falls, and are therefore important for people to strengthen.

He and other researchers said what's known about factors in falls could go a long way if disseminated nationally, similar to what the Yale group is doing in Connecticut. The potential value will increase as the researchers at Pitt, Virginia Tech, Michigan and elsewhere figure out more precise connections between the body's aging process and falls. Physical therapists and doctors could put that information into practice with specific exercise prescribed for older clients.

The potential benefit made enough sense to Forest Hills resident Kay Koch, 62, to make her volunteer to take a controlled spill in the lab for the Pitt study. She was protected from injury, unlike her 92-year-old mother, who fell at home and spent two days on the floor before anyone knew she needed help.

"This is good prevention," Koch said of the research study. "So many of us have older parents we're taking care of. ... So many have fallen and broken hips. It's not like when a child falls and picks himself right back up."