42 Ultras including 3 100 milers 3 100km’s and a dozen 50 milers, 60 standard Marathons and 11 IM’s over a 30+ year time span.
It’s a different sport for starters. It is a tough comparison frankly. If you mean which event is harder on you mentally or physically that is one thing. If you mean which event is more difficult to train for that’s another. If you mean which event is more competitve that is yet another.
IMHO IM racing is every bit as tough as a 100km road race, RACED. Key here is raced. 100 milers are another thing entirely. Few people are in a position to actually race this distance. For most it’s survival. As such, it could equate to a 15-17 hour IM finish depending on the athlete. But, here again, we’re trying to compare to rather different beasts.
100 milers and all Ultras are in some ways easier to train for because you are only concerned with one movement pattern. IM’s get very difficult to train for for those who are attempting to maximize their God given potential because of the puzzle of putting three sport training together. 100 milers are extremely hard mentally and tear you up real good physically. My recovery from an IM is nothing compared to the 100’s. But, when I did them, I raced them. I was looking to win or place highly. I gambled evertything. In fact, the only Ultra I ever dropped was a 100 miler at 80 miles. After a100 miler my legs were shot for a couple months. After an IM I’m ususally able to train more or less normally about three weeks later If so motivated. Mentlaly wiped out, but physically not too bad. The cross training effect applies to IM racing too I suppose.
I don’t like these comparisons because it misses the critical point that they are very different. Yes, they are both endurance events, but the transitions in an IM are very challenging and the drawn out duration of one movement pattern in an Ultra is very challenging on it’s own merit.
I know for sure, that the competition in a high profile IM is much greater and much deepr than almost any Ultra save perhaps, the World 100km road championships or something like Comrades in S.A. The depth in a high profile IM is much greater. There can easily be as many peopel in a single AG as ther are in an entire Ultra field.
As with anything it’s what you prepare yourself for. If an IM athlete jumps in to an Ultra without sufficient specificity, then they are going to have a tough go of it. And so woutd be the case with an Ultrarunner trying to wing it in an IM.
Graham Cooper winner of the '06 Western States 100 and 3rd this year, is entered at Canada Sunday. Take him aside and see what he says.