The Age MechanicsVisit the 3-D niche in the Town Center and watch yourself transformed into a computerized stick figure. Wave, and your figure waves back. Jump up and down, and try not to laugh.
On a simpler scale this is the same technology behind movies like Avatar, in which actors are plastered with body sensors to create lifelike animations on screen. But instead of turning Hollywood stars into otherworldy beings with blue skin, UW–Madison biomechanists are studying human motion to answer scientific questions like why do the elderly lose their balance? What is the best surgery for children with cerebral palsy? How do we treat knee pain in runners?
Motion analysis involves three main steps: 1) Use special cameras and sensors to record how the body moves. 2) Estimate the motions, forces and torque (‘kinetics’) of the bones and joints. 3) Build computer models that simulate movement and forces.
Simulating how healthy people move helps scientists understand changes caused by injury, surgery and aging. So what are we learning? Research taking place at the UW Neuromuscular Biomechanics Laboratory is trying to figure out why we lose mobility with age (consider: 20 percent of people age 65 or older become unstable walking more than a few city blocks).
In a recent study, participants wore sensors and ambled on a treadmill through a ‘virtual hallway’ projected on a screen. Under normal conditions, the young and older adults took about the same steps.
However, when the ‘hallway’ was made to sway, the older adults were more affected. Why? Researchers believe that as we lose physical sensation with age, we rely more heavily on visual cues to keep balance.
Such research could someday help diagnose and combat age-related “balance deficit.” For the one in three elderly people who take a fall every year, that could be more exciting than a movie script.