Half Ironman: Predicting Your Run Split Based on Your Bike Split

What run split can you expect in a half ironman based on your bike split? Of course, it depends on how conservative you were on the bike course. But we've done the analysis of several half ironman races to help you define your optimal bike/run splits.

On each chart, a formula defines the average; for example, at Switzerland, Run Split (y) = .67 * Bike Split (x), but with wide variation (higher r^2 = less variation). From there, examine the distribution of the squares; each represents a triathlete's actual performance. When you race, you'll want to be in either the lower left or upper right quadrants; those represent racers who balanced the run and bike well.

Mooseman Half Ironman 70.3 Results Analysis

Looking for a 6-hour half ironman event? Mooseman is the race for you. In both 2010 and 2011, the average finish times were identical, at 5 hours 59 minutes, and a few seconds. Among the 35 events on RunTri's Toughest Half Ironman list, Mooseman's keeps its rank at the upper end of the bottom 1/3.

Kansas Half Ironman 70.3 Results Analysis

It seems that the 2011 edition of the Kansas half ironman was a little bit tougher than in 2010, with an average finish time of 5:58 vs. 5:52. Still, Kansas remains ranked as one of the fastest courses in RunTri's Toughest/Easiest Half Ironman events.