the question wasn't who is more dominant- it's who's been working harder? and being a physics major, the definition of work can be seen as a.) calories burned, or b.) the distance a mass is moved, so i agree with the poster above as far as looking at pure work done.
i also wasn't saying that other athletes don't put in as much time preparing year around and everyday for their particular event, but when it comes down to the start of the race(or whenever isinbaeva feels ready to start), bekele spends 12 minutes more than either of the other two with his heart rate probably up around 170-190 bpm most of the time. even if richards or isinbaeva's heart rates get that high, and i would imagine richards' does, their heart rates aren't that high for 13 minutes.
and the fact that bekele was the 5k/10k world champ means he's that much more tired for these last 2 5k's he has to win in order to share the million. it's not like it takes the same amount of time to recover from an afternoon of pole vaulting as it does to recover from a 10k.