New research from the University of Illinois at Chicago suggests that the simple training exercise of catching a weighted medicine ball can improve balance and may help prevent falls in the elderly.

When someone is jostled by a bump or a stumble, the brain uses two strategies to maintain balance and prevent a fall, said Alexander Aruin, principal investigator of the study.

"When the perturbation is predictable, for example, if when walking down the street you see someone about to bump into you, you brace yourself," Aruin said.

The brain activates muscles in anticipation of the jolt.

The second strategy is corrective -- the brain engages muscles after the perturbation to prevent us from losing our balance, he said, which might involve taking an extra step, or changing body position.

As people age, they lose their anticipatory postural control, the ability to ready ourselves to maintain balance. As a result, there is no preparatory activation of muscles. This leaves them with only compensatory action. In effect, their resources for maintaining balance become more limited, and they become less stable and more prone to falls.

"We know a lot about the elements of postural control," Aruin said.

For the study, he and his coworkers began to investigate whether special training or exercises could enhance anticipatory adjustments and help people to utilize them.

In one of the new studies, Aruin and his colleagues asked a group of healthy young adults to stand and catch a medicine ball. In the second study, they asked the same of a group of healthy older adults.

The researchers measured the electrical activity of leg and trunk muscles to look for differences in the two age groups' ability to generate anticipatory postural adjustments both before and after the single short training session.

Training-related improvements were seen in both groups. In older adults, the researchers found that not only can they improve, but they also improve at performing a task that was not part of the training.

"There was a transfer effect," he said. "It tells us that -- potentially -- what people learn in the training might be helpful with other activities.

The findings are detailed in two journals: Electromyography and Kinesiology, and Experimental Brain Research.