Distance runner looking to do a Triathlon - what should I know?

i haven't done one but ive kicked the idea around a lot. I swim a lot for cross training whenever i have a niggle that im nursing, so ive looked in to doing them. It seems to me that people say the swimming is the hardest for a beginner but it seems like the most time is lost on the bike. I wouldn't focus soley on swimming because its "harder" Just .02 from someone with no experience

I've done a few sprints and trained for my first Olympic Distance this spring. Learned quite a few things this spring, during the race.

As mentioned above, your running background will be a huge advantage on the bike and (obviously) run sections, especially in a sprint distance race.

Move up to the Olympic and half iron distance races though, you'll need to get a decent amount of bike and swim time in. I did about 5 months of ~2x weekly swimming (building up from 0 to swimming about 1600-1800 yards comfortably) and built up to doing 4 bikes a week, 2 of which were ~10 miles as a double and 2 of which that were 25-35 miles.

That said, even though I got through the race OK, I do think I could have been another 5-8 minutes faster if:

- I did actual swim workouts. I was just swimming for total time/yards. Never did any 'speed' in the pool. I got through the swim without issue, I just was in the middle of the pack.

- Did longer 'tempo' bike workouts. Although I did do a number of 30s sprints and 3-4 minute fartlek workouts on the bike, I didn't do any 2-3x 10-20 minute "tempo" workouts where I would average 120-130% of race wattage. Although I averaged just under 200W and 21MPH, I didn't have the power overhead on the hills and lost decent time to others there.

- Did more bike-run bricks after long bikes. I had decent success off the bike on the sprint tris I did running 17:xx 5k's. Moving up to the Olympic distance though, my legs were just plain dead after that bike and I ended up running a 41:xx 10k instead of the 38-39 I wanted to. This was especially apparent the 2nd half of the 10k where my leg were struggling to maintain 6:45's

You're going to feel gassed after the swim if it's something new for you, but you will recover some on the bike. Hammer the shit out of the bike and trust your running fitness to get you through the run. The run will feel weird because your legs will feel like spaghetti for the first mile, but just remember that you will be running much faster than you feel. You will think you're running slow b/c you were going 20 mph on the bike, but trust me, keep your cool for the first mile of the run. All you need is a entry level road bike for now, but if you can rent or borrow some Zipp racing wheels, do it!

Bike isn't so bad. You can transition easily into it.

Can you swim? That will make a big difference. Helps if you can swim efficiently too.