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How fast can a human go? The answer, up to now, has been an average
of 68.73 miles per hour (about 110 kilometres per hour) over a test run
of 200 metres. Such feats can be achieved only in a ‘human powered vehicle’
– an odd-looking bicycle covered with an aerodynamically shaped shell within
which the cyclist reclines and pedals like crazy.

But Doug Boyer, a student of mechanical engineering from California
State University believes he can push the record higher still to surpass
even the elusive 70 mph barrier. According to Boyer, the answer lies not
with better, sleeker vehicles, but in calculating the best biking strategy
for the rider.

Boyer says he has worked out such a strategy. A series of computer simulations,
calculated using figures for the strength and stamina of world-class cyclists
and the physical characteristics of one of the best HPVs ever built, suggest
that riders could achieve a speed of 70.1 mph if they obey Boyer’s rules.
That is faster than the current world record set in 1992.

Boyer derives his strategy – which has yet to be tested on the track
– by juggling factors such as the vehicle’s air resistance and the rolling
resistance of the wheels at different speeds. He suggests that the rider
should start off pedalling at the highest level of aerobic exertion. This
would get the HPV up to a speed of 49.7 mph within 3 minutes.

At that stage, the biker should quickly increase the amount of exertion
in a smooth curve until reaching a maximum level of effort – with an output
of 1500 watts – in 27.6 seconds. By Boyer’s calculations, this should take
the biker up to the desired 70.1 mph.

Other strategies, such as pedalling as hard as possible at first then
tapering off the effort later, would not achieve as high a speed, Boyer
reckons. A rider who pedals as fast as possible at the start quickly runs
out of steam at the higher speeds when the drag of the vehicle is higher.
With Boyer’s strategy, the pedaller has power in reserve to counter the
drag at higher speeds.

‘At least from my research, it looks as though 70 mph is possible,’
Boyer says. He believes that improving the human factor is more important
than trying to build better HPVs. ‘Right now, we’ve got composite materials,
aerospace glue, titanium hubs, aluminium frames: we’re already pushing the
cutting edge of mechanics to build these things,’ he says. ‘From here on
out, it’s going to be a matter of making the engine – the person – perform
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