by Alex Hutchinson
I don't really have any definitive physiology to determine the exact distance at which Mo Farah and Usain Bolt would be evenly matched. As Ross Tucker explains over at the Science of Sport blog, Bolt and Farah represent two extremes of physiology with very different characteristics, and it's very difficult to know exactly where the crossover would occur. That said, I think this graph is interesting to consider:
What it shows is the relative contribution of aerobic versus anaerobic energy at various distances, based on calculations by Rob Duffield and his colleagues in Australia in these three papers. So, for example, a typical male 100-meter runner gets about 21 percent of the energy he needs from processes that require oxygen, whereas a 3000-meter runner gets 86 percent of his energy aerobically.
A couple of other things to note:
- The curve is a bit sigmoid: flat at the sides and steep in the middle. That tells us that there's not much difference between 100 and 200 runners, and not much difference between 1500 and 3000 runners (and there'd be even less difference between 5000 and 10,000 runners if we extended the graph out that far). In the middle, though, there's much bigger differences between, say, 400 and 800 runners. That means the range of distances where Bolt and Farah would be evenly matched is relatively narrow: if you choose a distance that's just slightly off, you may end up with one guy totally dominating the other.
- 600 does indeed look to be very close the middle. The 50-50 aerobic-anaerobic point looks to be a little shorter than 600. (It used to be that the mile was considered to be the 50-50 point for aerobic energy -- which, as a miler, I liked! -- but more recent calculations have revised upward the amount of aerobic energy used at all distances.) On the other hand, Mo's best distances are much closer to 100% aerobic than Bolt's are to 0%, so 50-50 isn't necessarily the right breakpoint anyway. And of course, energy systems aren't the only factor that will come into play to determine the outcome.
So my predictions? First of all, I don't think the race will happen. Much as I believe they both mean well, they both have unbelievable demands on their schedules, and I just don't see it working out. If the race is at 600, I believe Bolt has the tools to win. He's not a typical 100-200 guy, having shown the ability to run world-class 400s without specific preparation. However, I think maintaining the longer distance would be much more unfamiliar to Bolt than dipping down to a shorter distance would be for Mo, who after all does exactly that over and over and over in training. So assuming neither of them plan their season around such a race, I pick Mo over 600. If I was organizing the race and aiming for a 50-50 outcome, I'd pick somewhere between 550 and 580. Call it 565 -- and somebody call Mo and Bolt's agent to let him know that I've got it all figured out!