Martin’s report. The short: I did this on the vapors of bike fitness from RAAM, without any significant run training. The result was better than my 2014 IM WI! Nonetheless, my advice is not to run a marathon without run training. I felt SORE after that run!
The long: IM Wisconsin takes place in Madison, with a 2.4 mile single loop swim in Lake Monona, a 112 mi. bike ride on rolling hills with 5000 ft of climbing, and a marathon through town that has 2 steep climbs in it. Because of my crash at IM Chattanooga, I had not been able to run and swim for a couple of months, and when I started training for RAAM, I continued bike-only training to maximize my bike time. So I went into this race with just a few weeks of training short runs.
With nothing to lose, I decided to race “by feel” for the first time ever - no heart rate monitors or watches - and to run at a slow pace because my training pace at aerobic threshold, normally 6:55/mile, was a miserable 8:45/mile due to lack of running. Throughout the race, I went at a pace where I felt just faintly sick to my stomach, but could still digest what I ate.
My swim and bike were both faster than in IM WI 2014, when I did 10 IM for the season and was well-trained for it. The bike almost 15 minutes better! I chalk it up to improved fitness from RAAM training and to Superbike. Running a marathon unprepared is a whole different game. I was worried I might fall apart and start walking halfway through, so I jogged at a conservative 10 minute mile (estimated, since I had no watch) instead of my usual 8:30 pace. At that pace, I was able to eat a gel every few aid stations, drink plenty of ice-cold water from my trusty hand-held bike bottle, and to my pleasant surprise, ran all the way through the race, even up hills and through aid stations, without a stop. My marathon was only 7 minutes slower than in 2014, so I ended up doing better this time without IM-specific training! To be fair, IM WI was one of my worst races in 2014, coming as #8 of the season on the heels of IM Lousiville and IM Boulder.
Still, the word is out: you can do an IM and run the marathon even on 6 weeks of 10 mile/week run training, with no running for 9 months prior! Just make sure you ride 1000-2000 miles a month! The price: my legs were SORE as hell the next day.