so after lots of debate i decided to take a break from Ironman this year and focus on running.
I know i will lose a bit of ftp until I start picking training back up, but how do I lose as little as possible while riding as little as possible
Honestly I wouldn’t worry about it much. As someone who has taken varying breaks from the bike for injury or motivational reasons, it always comes back in a matter of months. The first couple weeks are always rough but the legs remember pretty quickly.
Getting on the bike once a week at all would save you a week of awkwardly pedaling around when you go back to a bike focus. Tempo efforts once a week might save another couple weeks of slowly ramping power back up. But either way, it doesn’t take long to get your ftp back where it was. Legs remember.
The marathon training alone will do a great job maintaining your aerobic fitness. I don’t think it would take more than 1-2 short hard sessions each week on the bike to maintain most of your bike-specific fitness - I think the key is making sure those don’t derail your running workouts
I did this back in 2013. Spent 7-8 months with almost a total run focus, marathon was absolutely my A race that year, but I also had a 100 mile cycling sportive/gran fondo event 10 weeks after the marathon which I wanted to be in good enough shape for to hang with (aka try and drop…) my cycling buddies.
Approach I took worked pretty well. That was to focus on building run volume by running 6 days/week, but with very little speed work or intensity (basically the BarryP plan). I got my intensity on the bike e.g. at a minimum I’d do one bike session per week, and it would typically be 2 x 20 minutes of threshold work. I’ve found that to be the single best workout for maintaining FTP (though at the time I wasn’t training with power, so it was an RPE/HR threshold session).
My experience was that I didn’t lose much in the way of cycling power, and once I’d got through the marathon and started doing some decent bike miles again the fitness very quickly transitioned across, plus I had a renewed enthusiasm for bike training after such a long period of pounding pavement. If my marathon training had involved more speed and intensity I might have struggled to find the energy to do high quality cycling sessions, but I know from bitter experience that I need to be very careful of high intensity work when running as I’m injury-prone.
+1 Don’t worry about it. Pick up the bike 3 months out from your next tri and it will all come back. 2x 1 hour FTP work on the trainer, and 1x long weekend ride, weekly, and you’d be back.
Same experience for me as the others…I’ve dropped the bike completely, and it took about 8 weeks to recover FTP. I’ve also kept a single bike Sweat Spot session (2x20) per week, and lost virtually nothing. I found the SS (90% effort) session to be more compatible with the run training, than a full FTP (100% effort) session which kinda wrecked me for downstream running.
YMMV.