A bike is certainly possible. But I suspect it's a driver because of the phone he carries. Also, the guy is apparently only capable of running 8:30-9:00 pace when running close to all-out for those sections of the course before the chip mats. He'd have to run/walk back to where he locked the bike, which would eat up time, unlock the bike, and ride a section parallel to the course, which would all take time. Since his actual running is 2-3 minutes slower than the pace he's trying to appear to run, he doesn't seem to have that much time to waste. With a driver, he could be picked up at spots that were prearranged or called in (phone remember,) and then he'd have time to recover between bursts of his fartlek session.