This bicycle is based on a conventional electrically assisted bicycle, capable of about 15 km/h on a level road, but with a more powerful motor and larger battery.
The difference is in the control unit, which incorporates a system for slowly and subtly decreasing the amount of electrical assistance
When the rider first uses the bike, it provides 100% of the tractive effort, but will obviously slow down somewhat on up gradients. A green light indicates that the bike is traveling at "target" speed; to keep it on, the rider has to pedal up hills - using the gears if necessary - but gets a free ride on the flat.
However, over a period of weeks, the control system very subtly reduces the amount of assist provided by the motor. So the rider has to pedal ever so slightly harder on gradients to keep the green light on. A chestband monitors the pulse rate which is recorded by the control unit.
Eventually, the rider will need to pedal slightly to keep the green light on when traveling on level roads.
As time goes on, they will pedal more and more, but since they will gradually become fitter, they won't notice just how much more effort they are inputting.
Eventually, they won't actually need the electric assist at all.
By this means, even very unfit and overweight individuals can experience a low impact exercise regime, and also cover short distances quickly and efficiently.