Here is a guy who was a double amputee who competed in rugby, water polo and tennis and only took up running seriously in 2004 after being prescribed it as part of his rehabilitation from a rugby injury.

Pistorius holds three sprint world records for disabled athletes Oscar Pistorius has run the 400m qualifying time for both August's World Championships and the 2012 Olympics.
The South African double amputee, who runs on carbon fibre legs, clocked 45.07 seconds in Italy.
Pistorius, known as 'Blade Runner', was 0.18 seconds inside the 'A standard' time and could be selected by South Africa for the London Olympics.
A congenital condition meant Pistorius was born without fibulae - lower leg bones - and led to the decision to amputate both legs below the knee when he was 11 months old.
Oscar Pistorius closer to fulfilling Olympic dream
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