Training Commitment

It honestly depends on how efficient you are.  Don't get me wrong, IM training takes up a good bit of time, but it's not 20+ hr week after 20+ hr week.  Done right, IMO, you will have some 18+ hr weeks here and there, but they are not all the time.  Plus, the bulk of that comes with long rides on the weekend.  Again, you can be done and back home by 12 -1 if you do it right.

Can you cross the finish line on light training...sure.  But really look at your schedule and I would wager there is time there.  I am normally done with my training by 7:30 each night.  So, in short, it can be done.

If it makes you feel any better, I did my first Ironman on a max of 12 hours/week (only twice) and most of the time was around 7-10 hours a week.  I finished in 11:24.

What I did have was an excellent base for 2 years, especially in cycling.  I also trained consistenly and frequently focusing on building exceptional skills for efficiency.  For instance, I had no time for 2 hour bike rides during the week.  But I did ride during the week (on an indoor trainer) for anywhere from 30 minutes to 1 hour three times per week.  Add the long ride on the weekend and I biked 4 times per week.  I consistently swam 3 times per week.  I ran three times per week with one run being a brick.  I alternated long run weeks and long ride weeks.  Every workout had a purpose with quality being of utmost importance.

I am very injury prone due to some anatomical "anomalies" so a lot of weekly hours just wouldn't work for me.

So, it can be done!

Andi

Forgot to mention, in Gale Bernhardt's Training Plans for Multisport Athletes there is a plan "13 weeks to a 13 hour Ironman" and the peak weekly training is 13 hours.  Going into the plan I think you need to have a base of around 8 hours a week of training, but don't quote me on that.

Andi

I'm currently using the BT intermediate IM plan.  So far it seems to be about 13-15 hours a week.  That is about the max I felt comfortable giving to it...  I have seen some plans that call for weeks of 20hrs or more, and felt like I wouldn't be able to do it, and then I knew I would feel bad (like I fell short of the goal or cheated myself).  I wanted a plan that I KNEW I could complete, and feel a sense of accomplisment week after week.

However, this is my first IM and my goal is, first and foremost, to finish strong.  I could have probably gotten away with less training, and still survived, but I do want to be a little competitive.  Check in mid Nov. and I will be able to tell you how it went.

Yeah, no doubt, you want to go sub 11, you do that.  You're just fast on the bike and run (and swim) if you got all that done in 18 hours a week

Comparing my hours to say someone like Fred it is totally different as he is much faster at everything so his 110 mile ride may take 1-2 hours less than mine.

So it kind of tough to compare hours from one athlete to another unless you are pretty close to your paces.

I think Fred brought up great points.

Why do an IM next year? They will always be there but your child will be a baby and a toddler just once. With young children it is the most time intensive time parenting. I have 5 kids and never could train like I do when they were little..time wise sprints and Olys would have fit. 

The highest training hours are really only about 2 month before your IM taper so about 10-11 weeks out from the IM.  

I coached an athlete last season who averaged about 11hpw and peaked just over 14, IIRC (it's close to those numbers anyway) and he was able to finish with a solid time so it is definitely possible in the range that you are considering.

However, if you are going to attempt this, I would hope that you either have a very solid understanding of endurance training or you should hire a coach.  The reason for that is in order to train effectively for IM on reduced training hours you are going to need to manage your training load (through intensity) very carefully and will probably be flirting with injury as a result.

Shane

I bolded the VERY important part.