Lack of specialist equipment and top-class competition are almost insurmountable barriers to even the most physically gifted athlete such as Niyonshuti, but by finishing fourth in last year's African Mountain Bike Championships he booked his place on the starting line at Hadleigh Farm.

CNN: August 10, 2012 -- Updated 1021 GMT (1821 HKT)

She is the person up in Juneau, Alaska who's planning to ride 350 miles on a mountain bike through the snow on the same trail that's used by the sled dogs.

NPR: Got Snow? Add Bicycle.

Mr Moore-Robinson, from Coalville, Leicestershire, was taken to the hospital's accident and emergency department after a mountain bike accident in Cannock Chase.

BBC: John Moore-Robinson Stafford Hospital death: No charges

He'd visited the U.S. as part of Team Rwanda, a fledgling race team sponsored by benefactors including mountain bike pioneer Tom Ritchey.

WSJ: Adrien Niyonshuti: A Long, Amazing Ride to the Olympics - Jason Gay

"The more you know your teammates, the less likely you are to take comments made in the midst of sleep deprivation personally, " says Sara Ballantyne, 38, a professional mountain-bike racer who helped lead Team Vail to victory in last year's Eco-Challenge in Morocco.

FORBES: Hypothermia for Fun and Profit