This video comes from inCycleTV and it gives some insight into the reality of the difficulty of Professional Racing.

The race is this week's Tour de Suisse, a 9 day stage race. This is from Wednesday's Stage 5 which has two Cat 3 climbs, two Cat 4 climbs, is about 110 miles, and the riders have been in the saddle for about 4 hours. This is the final couple of minutes:

http://www.youtube.com/watch?v=QE97iUvSHk0&feature=share&list=UUgy3VdQYAYm33C57aFUfki

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