Phil Clark wrote:

Cycling's too efficient, it takes all the hard work out and is
therefore not an excellent form of exercise. Walking and running are
much better...

Maybe you should switch up a gear - the hard work will suddenly be put
back in!

I'm wondering what can be done to bikes at a reasonable cost with
semiconductors these days. ISTM they'd be a lot more pleasant to ride if
instead of having to adjust gears to suit the terrain you could control
how hard the resistance force is. Does anyone yet make bikes with
electric transmission that sophisticated yet? And if so, how much do
they charge for it?

--
Aidan Stanger
http://www.bettercrossrail.co.uk