Am I ready to take on Ironman 70.3? Bike training questions

Cycling is the easiest of the three to build fitness. If you think that cycling is about leg strength in general, then you are using the wrong gears. You can easily build up to 56 miles, especially if you are as young as I think you are. You might have to cut back on running in the beginning, though. Not only will there be an overlap of muscle usage, the amount of time/energy spent training could be a bit much. You might also just plan on doing shorter rides 2-3 times a week when you start or you will become well acquainted with the term saddle sore.

As a personal example, I went from barely being able to ride 10 miles to doing the MS150 (150 miles in two days) in about two months, and I wasn't running more than 5 miles at the time. You can definitely do it, but ease into it a bit more than slowly than you are thinking.

Yes. You have plenty of time. I doubt you have "appalling" leg strength. Do you currently own a road bike? You already sound fit so building up to 56 miles won't be a big deal IMO. Building your leg strength/endurance to go fast will take a little longer. Short runs off the bike I found useful when I first started training for triathlons just to get used to the feeling but that feeling always ends up being pretty much the same off the bike. But it doesn't hurt.

You should have time. A standard beginner 70.3 training plan is about 20 weeks - sometimes 24. But that starts with a premise of some cycling.

My question is actually that based on your statement that you have zero cycling experience ... do you have also zero triathlon experience? Do you have a bike? There is a learning curve with road cycling if you've never done it that might eat up some of your training schedule. Not undoable but I wouldn't leave that to the end if you have a choice.

Given that you have a stronger swim and run background than a lot of people who do full IM, I don't think this is a poor life decision at all. I also come from a strong distance running and swimming background and, to be honest, did not find that it was all that difficult to build up bike mileage to finish a HIM. I think I'd never done a training ride of over 90 minutes until about five months before that race. But a few caveats--you do need to have a bike, and preferably a bike that's reasonably comfortable and that you enjoy riding for 3-4 hours. Spin bikes are okay for occasional workouts, but you really should get a road or tri bike (if you don't have one already) and spend lots of time riding it on the trainer and on the road, if nothing else to work on handling skills and confidence, and iron out any comfort issues with fit, saddle, or position well before the race.

I think with your endurance background, assuming your butt is happy with your bike/saddle, it won't be hard to build up to 56 miles of cycling. You do need to realize that a 13 mile run after that long a ride is a different animal than a stand-alone half-marathon. The better your bike fitness is, the better your run will turn out.

You are right about one thing--distance running and cycling do work somewhat different muscles. Biking FAST requires more glute and hamstring power than typical skinny marathoner types with no bike background bring to the table. I've really struggled with the bike--going slowly from BOP (123rd out of 136th on the bike leg of my first Oly--and it didn't involve any mechanical problems!) to MOP to (jn a good race) finishing in the top 1/3 of the overall field (both genders) and maybe the top 10-20% of my age group. It still holds me back from winning my AG in many of my races. If you have the goal to be competitive in triathlon and have little cycling background, it's in building bike speed/power where the "brutality and extreme discomfort" are going to come in. If your goal is just to finish a HIM, though, that's probably not the case.

I was wondering the same thing.

I'd suggest to the OP to plan on an olympic, at the appropriate time, to get a sanity check on the progress and doing at least 1 real triathlon midstream.

Same as everyone else.

Do you have a road bike? Have you rode your bike for any kind of distance?

Sounds like you have the physical tools and plenty of time to get this done. Look into some of the training plans I think your going to need to adapt your plan to be more balanced. 2-3 of each per week.

Thanks for all the feedback! I will be getting a road bike in September and intend to try and do my longer rides on this. Also no, I have never done a triathlon, and I am not trying to compete, I'll be thrilled if I cross the line even one minute before cutoff :')

You might want to see if you can find a Sprint Tri in your area yet this fall. It would be a fantastic experience for you to work out a TON of stuff as you start prepping for the HIM. But like everyone said, you can certainly do the 56 biking with your current fitness and that much time. Others have said it, but I would also caution to start more gradually on the bike. Maybe a couple short rides the first week, maybe three the second week, a little longer for a couple of the 4th week rides and so on . . .let your body adapt