i saw this box in the rubbish outside a sports shop and i was quite shocked. they have exercise bikes for 4 to 8 year olds ! You can buy it here if you are interested. but don't tell your child it was my idea.

the great thing about this bike is you can put your kid in front of the telly, give them a can of coke and chocolate bar in your nice warm house so they can get fit, instead of running around in the garden/local park.