One of my biggest fears when I was training for my first Ironman triathlon last year was that I might not finish. Initially that I wouldn’t make the bike cutoff, but then potentially with the run depending on how things had gone thus far. So exactly how slow can you complete an Ironman without getting disqualified?
So I actually mapped it out, and I want to share the information! Each race is a little different in terms of its cutoff times, so use this as a guide but check your Athlete Guide for more specifics as to your race. I was looking at Ironman Louisville and Ironman Wisconsin guides when I wrote this. For your race, please check the most up-to-date Athlete Guide on the race website.
Ironman- How Slow Can You Go?
You have to swim 2.4 miles in 2 hours and 20 minutes. This translates to a 3:37/ 100m pace. If you swim in a yards pool, then your slowest 100 pace is going to be 3:18/100yd.
Swimming for 2:20 will get you out of the water at 9:20 AM (assuming a 7 AM start, the standard at most Ironmans).
Let’s just assume a 9 AM start. You have to be at 60 miles by 2:45 PM —> this translates into a 10.43 mph pace.
If you have to hit 112 miles by 6:20 PM, then you need to ride at an overall 12 mph. If you have to complete 112 mi by 5:30 pm, that’s an overall 13.1 mph bike pace.
If you took your whole 2 hours and 20 minutes on the swim, and don’t get onto the bike until 9:30 AM (you got out of the water at 9:20 and then took 10 minutes in transition to get to the bike), then you have the following times:
- Get to the 60 mile cut-off by 2:45 PM –> you need to ride at 11.43 mph for the 5.25 hours
- Go the full 112 miles and arrive back by 5:30 PM –> you need to ride at 14 mph for the 8 hours
- Go the full 112 miles and arrive back by 6:20 PM –> you need to ride at 12.67 mph for the 8 hours, 50 minutes
Assuming a 6:30 PM start onto the run course, and a requirement to pass the 13.1 mile mark by 9:45 PM, you’d have to run at a 14:53 min / mi pace to complete that 13.1 miles. To get to 26.2 by midnight (having started at 6:30 pm), you need to run an overall 12:35 min/mile pace.
My goal in this is not to scare anyone, but to put the paces/speeds out there for the bare minimums. These are assuming you are taking all of your time on each of the disciplines.
What should I do?
Gather up your training paces, or benchmark tests. Be honest with yourself about the Ironman and where you are in training:
- What was the speed of your average long ride?
- What about your average long run?
- What’s your average swim pace?
- What sport are you most nervous about?
Play out the scenario with your conservative paces — remember what you do in training is likely what you’ll do on Ironman race day. So for me last year, I predicted a more realistic timeline that I was able to share with friends and family of what I thought I’d do. This helped my fan club with knowing when they might expect to see me. I shared with them all of the scenarios so that they’d have that information.Just how slow can you go in an @IronmanTri ? Figure out if you'll finish in time! #Triathlon Click To Tweet
Some calculators you can use once you get your benchmark paces:
I took my paces and turned them into estimated times:
Swim: 2:10/ 100m —> 1:23:41
T1: 10 minutes
Bike: 14.5 mph —> 7:43 15.5 mph —> 7:13 16 mph —> 7:00:00
T2: 10 minutes
Run: 12:30 —> 5:27 total.
I then translated those estimated times into “Time of Day” predictions that I could share with my family and friends to help with them spectating – both at the race and virtually:
7:30 AM Start:
Swim out/Bike Out: 9:33 AM
Bike In: 4:33 PM (16 mph)
Run Out: 4:43 PM
Finish: 10:15 PM.
While that didn’t happen (unexpected things always come up on race day!), this did give everyone involved with race day a better idea of what was going to happen when! I periodically did my check-in on paces starting a few months out (hey, I’m a planner), and then shared with my family & friends a week or two before IMLOU.
I hope you found this informative and helpful!