I've seen this discussed a few times

Of course it assumes proper fitness and pacing

I was going to say that LP is likely a much harder course than any open marathon you have done, so a 2:55 at a flattish open marathon likely translates at best to a 3:30 at LP assuming you have the swim and bike fitness AND you pace and fuel well. Best of luck. Of course could sandbag the swim and bike so you run a 3:20, but you'll have to give away a lot more than 10 min on the swim-bike to gain those 10 min on the run.

Your open run times are all very similar to mine though I've never actually run an open marathon, but I'm assuming I'm in the 2:55 range. I raced at IMLP in 2019 and ran a 3:31 on a relatively hot day. I can power through hills pretty well, and power through you must! There main hill section that you do twice is pretty rough. I even saw the amateur winner of the entire race walking a bit at the top of the last hill around mile 24 when I was headed out down the hills for my last lap.

Depending on your bike fitness, you can probably run a 3:24-3:32, but that's still a big range. It's about 1000' of gain FWIW.

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I should have clarified that I did the 3:27 at IMLP in which case you seem to be pretty spot on.

The biggest factor is how hard you go on the bike. I tend to go a bit too hard on the bike, and in my last Ironman (I’m a 2:40 open guy) I had to walk lots and struggled with a 3:23. I think it’s only at the tip of the spear where guys can go less than 30 min from their open times

That chart had been right on for me at the sprint, Olympic and HIM distances.

Also seems to work for the OP :-) Somewhere along the 57VDOT line....

you aren't that far off. I've run a 3:30 (IM) and am a 3:05 ish open. Because I was a swimmer I suspect the swim takes a lot less out of me than you.

seeing that, yeah, you are pretty close.

Everyone on ST always says the biggest factor is how hard you go on the bike. Let me simplify this for all of you. Do 5.5 hrs ride totally fresh followed by a 30 min easy run.

Then next weekend do a hard 90 min swim followed by a 4 hrs ride at the same power as the previous week. Now do the 30 min easy run.

I can guarantee that the week 2 workout will be way more uncomfortable. The swim has a huge drain on energy and everyone acts like it is incosequential when it has huge consequence. If we want to get some perspective, after Lionel Sanders does the swim in Kona he is a top biker, but he just as often struggles. Yet, completely fresh he biked 51.3 kph which is faster than Jens Voigt, faster than everyone in history in Canada. With that level of biking Lionel should be waaaaaay faster biking in Kona, BUT that swim takes so much out of him because he's just not sufficiently swim fit relative to other pros and most age groupers are not sufficiently swim fit for the 3.8km to not have a huge impact on their day and everyone overswims (by the way most people also claim they don't kick in the water, but when you get in every race the people around you are kicking like maniacs depleting glycogen they will need later in the day on the run).

By the way, your 3:23 marathon is not bad for a 2:40 open guy considering you walked. You just have to walk 1 mile and you lose 13 min on your split. (walking is 20 min per mile, running is 7.5 at your speed). So if you walked a mile the rest of the run you did in line with you 2:40 open marathon. I am also guessing with a 2:40 open marathon, you don't have the body composition of a top swimmer and maybe not built like a good TTer (but possible you are). If you are built more like pure runner you will inherently struggle with how much energy you have leaving T2

I'm around the same speed, race wise - 1:20 PB in the half. My best 70.3 run and IM run came in 2019 - 1:27 and 3:22 respectively. In terms of the LP course, I did the race in 2018 and was 1st in my AG and on pace for a run in the upper 3:2x range, but had to pull out with an injury (peroneal tendon issue that had popped up two weeks before the race). That hill, especially on the 2nd time back into town, isn't enjoyable! I think that 3:20-3:25 is do-able if paced correctly on the bike and run (and, as Dev said, you have the swim volume needed to not have it be detrimental for the overall race).

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Thank you for the feedback. I tend to agree with Dev that swim conditioning is big limiter on many triathletes potential....mine especially. I believe I have followed a couple of your posts on here Nate. If i'm thinking of the right guy congrats on Kona.

Mine too for Oly, HIM and IM except 5k sprints are a bit faster, by almost a minute. The IM prediction matches my last IM split exactly although I bonked and had to stop, eat and walk a couple of miles... wasted about 20 minutes. Maybe bonking is included in the calculation :)

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What's your CdA?

I think we have similar run fitness (I used to be faster, but I’m not now) and my time at IMLP was 3:28. I did pace the bike quite well, but I also paced the run poorly and blew the last 8 or 10 ... lesson learned? Pacing the bike well causes you to run too fast, so don’t do it, ha.

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Dimond Bikes Superfan

If you have good swim and bike fitness I would say 12-20 minutes slower than your open marathon time if you pace
correctly.

That’s pretty spot-on! Shows I underperformed my 70.3.

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Aaron Bales
Lansing Triathlon Team

In 2018 I ran a 2:56 open marathon in the spring and went on to run a 3:16 marathon off the bike in Lake Placid. I'm not sure if that says I underperformed my open marathon or not, but I felt like with training as long as I hit my nutrition right that was the key factor in running 7:30s consistently.

I just realized I have my own stats for open marathon + IMLP. 1999 IMLP I ran 3:43 if I recall correctly. 7 weeks later I ran 2:56 at the Toronto marathon on the old course (it was actually equally hilly to IMLP).

For that IMLP I was highly undertrained for the swim and bike. I was barely swimming 4km per week for 4 months before for the swim and for the bike I had one hard 90km ride per week one hard 90km bike on the weekend and I had daily 20km per day of bike commuting.

My run volume was excellent for a triathlete. I ran 60 min per day at lunch time (typically 13-14km of hills and intervals and I ran every Sunday 2-3 hours. So 7-8 hrs of running.

Basically my program was bike commute to work Mon, Tue, Thu, Fri, Ride 90km super early before work on Wed and 3 hrs training blocks on Saturday before 9 am and Sunday before 9 am as my son was 3 years old at the time. On Saturday hammered out another hard 90km and on Sunday the longer run (2-3 hrs). So basically I was getting 90km per week of running, 270km per week of cycling, no long rides, and Tuesday and Thursday before biking to work I could cram in a 30-40 min swim on the way to work (~4km total). So if I look at that 2:56 marathon after the 3:43 run at IMLP it make 100% sense. I had run fitness, but insufficient swim and not enough long rides. I did have one 180km ride on a training day of vacation in lake Placid, and I raced two half IM's that I kind of kicked ass on (faked the swim had a solid 90k ride and ran sub 1:30). Half IM was perfect on that training plan, but not IM. You can't fake a 3.8 km swim and you certainly can't hammer a 180km ride on no riding volume and expect not to bonk. But I had endless run endurance even coming to T2 pretty well depleted (I tried to hold back, but even then, it still hurt leaving the oval). I just needed to top up and go.

I also had a few years when I ran 2:59 to 3:03 range in Boston and ran 3:42/43 at IMLP (I have done IMLP 11 times)...again on the run focused program that worked well with a young family. The swim and bike were just too time consuming. Run was bang for the buck on time.

If I have a chance to get into an IM next year, I think my run will be OK for my age group (now 55-59) and my swim form will be excellent (last year I ran 300 hrs and swam 275 hrs and biked 275 hours). I am hardly doing an biking now, and if there is racing, I will be able to ramp the bike quickly to do well at half IM, but unless I am registered for an IM, I can't bring myself to the requisite indoor biking.