Need advice on what to wear in my first IM

I have always raced an entire race in a single outfit.  I have raced in one piece tri suits and 2 piece.  I prefer the 2 piece for the reason you mentioned.  I like a top which has pockets in the back.  Recently, I have been using shorts which have a little pocket in the back, which I really like (great for a gel flask on the run).

For IM racing, it's a long day, so comfort is important.  If you think you can handle the comfort of the same clothing all day, you should do it.  If you think it will just be too uncomfortable, than think about a change.

Just my 2 cents.

I'm having some of the same questions.  I normally race in a tri suit the entire time (up to the HIM distance), but sometimes my sleeveless tri top causes an abrasion on my right under arm.  In the shorter races, it gets rubbed raw a little and hurts a little.  I fear that in an IM, it could really start to hurt a lot and/or bleed.

My plan is to wear a two piece tri suit for the swim and bike, then just change tops to a loose dri fit t-shirt that I know is comfortable in my long training runs.

What do you wear when you train? Do the same! Nothing new on race day.

I would skip tri suit option as it is a pain to use porta potties.

I'd sugget trying peeing on your bike...saves time and when you are racing against the clock can be a huge time saver..really I'm serious. Lots of folks do it..use a water bottle to squirt to clean yourself off. Some race reports folks report losing 15' in porta potties..huge when cut offs are looming.

I wore my sports bra and tri shorts for the bike under my wetsuit. I had practiced my IM distance swims in the same clothes under my wetsuit and worked well with no chaffing.

I just put on dry bike jersey in T1 and had a great helper who would take the ziplock of stuff for my pocket and would ask which pocket and put the stuff in Left, middle or right pocket.

I changed my tri shorts to different tri shorts (both were oomph) for run...it has built in race belt and has 5 pockets which are great for running when I had to carry everything with me unlike on the bike where I have bento box ect. I changed to my BT tri top for run. I changed my socks as well but silly as I had to go through 4 inch huge puddle to exit women's change tent so my feet were soaked within 1 minute of changing. The idea of wearing same tri shorts for 18-19 hours as a women seemed gross and not so healthy since I knew I'd be peeing in them as well.

What have you TRAINED in?

For a woman, I'm thinking a 2-piece TRI SUIT would be better suited for the one big "challenge" - port-a-potty visit.  Or better yet, have you tried learning to pee on the bike and run?  Serious question only you can answer and feel comfortable with.  The tri suit doesn't have as much padding as bike pants/shorts so you are better for coming off the bike and into the run.

If you are worried about cutoff times, make sure to have something that will be more "wick-free" so as to keep the sweat off better and is more breathable and comfortable.  BUT, if you haven't been training in it, then NOTHING NEW ON RACE DAY!

I wore a singlet tri suit last year and loved it, except for one thing - it didn't have any pockets.  Next year for IM Moo I'll be training and wearing a 2 piece that has pockets.

I do believe it is tradition to do your first one naked

Seriously I didnt know what I was really going to wear until I got into transition.  I didint know what the weather would be like so i had a few things in both bags.  I did wear bike shorts- then changed shorts for the run.  It takes like 20 seconds to change- not a big deal.

 I was covered in salt after the bike...and it wasn't from the ocean   you won't even notice, I don't think.  I wore a one piece and was fine.  Unless you have to doody during the race, it's not a big deal...to pee, just pull the leg up and over.  My suit fit like a glove and I didn't have to worry about a binding bike jersey or the elastic from shorts cutting me in half.  I threw a long sleeve tech top n for the 2nd loop of the run.

However, you have to do what you feel comfy in...Get what you think you might like now and try it on some long training sessions....and be prepared for all sorts of weather-hot, humid, cool, dry, rainy.