RunTri: Ironman Wisconsin 2015 Results Analysis: Overall, by Division, by Splits; Correlation b/w Bike and RunTimes

By Raymond Britt

Despite a beautiful day with ideal race conditions, our results analysis indicates the 2015 edition of Ironman Wisconsin was, counterintuitively, the slowest/toughest since 2009, with an average finish time of 13 hours 33 minutes. By contrast, the 2013 IM WI averaged 13 hours, 14 minutes.

Fast Facts, with detailed charts below:

Finishers: 2,558; DNS = 16%, DNF = 6%
Average Finish Time Overall: 13:33; Compare vs avg time for all Ironmans = 12:35
Average Swim: 1:21 = 10% of average total time
Average Bike: 6:42 = 49% of average total
Average Run: 5:09 = 38% of total
Average Transition: 0:20 = 3%
Correlation Between Bike and Run r-squared: 0.24 = low correlation = more than normal difficulty for many athletes seeking to find the right balance between bike and run effort
Finishers in Final Hour: 239, vs 165 in 2013, further indicating more suffered on the run

Our theory regarding the slower average time is one you might not expect: that because conditions were optimal, athletes may have unconsciously felt encouraged to ride the bike course faster than normal.

I've finished Ironman Wisconsin 5 times, and know very well: the bike course is deceptively difficult, and those who go out too fast tend to suffer on the run. That's what we saw in 2015, indicated by the lower correlation between bike and run splits. (also see our analysis of finishers per hour, further below).