At-home fitness DVDs are a booming market, especially those targeting seniors -- but a new study attempts to find out if they work.
 

"There are tons of DVDs out there, 20 percent of them are purchased by older adults, and with few exceptions there is no evidence that they work," says University of Illinois kinesiology and community health professor Edward McAuley.
 

To find out, McAuley and his team recruited 307 U.S. seniors aged 65 or older for the study. Half of the participants used a fitness video at home, while the other half (the control group) watched a video on healthy aging.

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In the study, the participants worked out to a fitness video called FlexToBa, which the researchers designed to improve flexibility, strength, and balance -- three components that are key to maintaining an independent lifestyle in older adults. Subjects used the video three times a week over a period of six months, with new challenges added each month to keep participants engaged.
 

Participants were asked to complete daily exercise logs and received short support telephone calls with exercise tips every other week for the first two months, and then every month. The control group also received the telephone calls.
 

At the end of the six months, those who stayed with the FlexToBa program saw "clinically important" improvements in scores on a battery of tests of physical function as compared with the control group. Unlike those in the control group, FlexToBa participants saw increases in their upper body strength and balance and were able to maintain their previous level of lower body flexibility.
 

"This has important implications for an increasingly elderly population who are at risk for subsequent declines in function and increased disability," McAuley says. "We now know that this type of program can help to prevent that decline, and possibly reverse it."
 

The study appears in the Journals of Gerontology Series A: Biological Sciences and Medical Sciences.