Swan calculated how much TV each step should earn by comparing daily recommended doses of both, and the formula basically works out to one minute of TV for every 100 steps. Cliff Randall, at Bristol University, England says the shoes are a good idea, but the main challenge is making a sensor that will resist tampering or other efforts to thwart the system.
Sports shoes that work out whether their owner has done enough exercise to warrant time in front of the television have been devised in the UK.
The shoes - dubbed Square Eyes - contain an electronic pressure sensor and a tiny computer chip to record how many steps the wearer has taken in a day.
A wireless transmitter passes the information to a receiver connected to a television, and this decides how much evening viewing time the wearer deserves, based on the day's exertions.
The design was inspired by a desire to combat the rapidly ballooning waistlines among British teenagers, says Gillian Swan, who developed Square Eyes as a final year design project at Brunel University in London, UK.
Once a child has used up their daily allowance gained through exercise, the television automatically switches off.
Daily amounts Swan calculated how exercise should translate to television time using the recommended daily amounts of both.
The first prototype has two sensors in the sole - one that record steps and another, in the heel, that can be used to send data to the receiver with a firm stamp.
"It's a good idea for integrating sensors into clothing," says Cliff Randall, at Bristol University, UK, who believes computers will routinely be built into garments in the future.
"It's got to be easy to install and difficult to bypass," he adds.
Existing pedometers normally clip onto a belt or slip into a pocket and keep count of steps by measuring sudden movement.
Swan says these can be easily tricked into recording steps through shaking.
But her shoe has been built to be harder for lazy teenagers to dupe.
"That was one of my main design considerations."