Booster Blades?

Booster Blades.

It is like a two in one item, the Booster Blades are worn like skates but pedal to propel forward.

The skate boot is mounted on a hinged frame. When you lift your foot, the wheels move closer together; when you push it down again they move apart and a drive belt turns the back wheel. As you lift your foot again, the wheels move together again and the drive belt re-winds ready for the next stroke. In this way, the up and down pedalling motion propels the rider forwards, building up fast speeds with little effort.

There is a brake operated by tilting the foot back on the heel, which can be operated at any time, even if you are half way through the pedalling motion. There are even plans for a mechanism for changing gear, which the inventor is hoping to introduce on later models.