Complex sentence: The first three athletes to finish the Prologue were each rewarded with a five-minute headstart in the Red Bull X-Alps race start on July 5 and an additional Led Lenser Nightpass to journey through the night, which is normally a mandatory rest period.
Split into simpler sentences: The first three athletes to finish the Prologue will each be given a five-minute headstart in the Red Bull X-Alps race start on July 5. They'll also be rewarded an additional Led Lenser Nightpass to journey through the night, which is normally a mandatory rest period.