The finding is based on a study by Abby King, PhD, professor of health research and policy and of medicine at the Stanford Prevention Research Center, who found that specially programmed PDAs, or personal digital assistants, can prod middle-aged and older people exercise more.
"Portable computer devices are useful because they can be carried around throughout a person's day. Such devices represent one kind of strategy for being able to provide individuals with the help and support they need, in a convenient, real-time context," King said.
37 volunteers took part in the study. They were randomly assigned to an eight-week program in which they either received a Dell Axim X5 PDA, or traditional handouts related to physical activity.
The Dell Axim X5, chosen for its large-sized, easy-to-read screen and good contrast, was fitted with a program that asked participants approximately three minutes' worth of questions.
Among the questions: Where are you now" Who are you with" What barriers did you face in doing your physical activity routine" The device automatically beeped once in the afternoon and once in the evening; if participants ignored it the first time, it beeped three additional times at 30-minute intervals. During the second (evening) session, the device also asked participants about their goals for the next day.
After eight weeks, the researchers found that while participants assigned to the PDA group devoted approximately five hours each week to exercise, those in the control group spent only about two hours on physical activities-in other words, the PDA users were more than twice as active.
"The PDAs can really keep on you," King said.