I set a conservative ftp target for the first long race prep session, then bump it up each week while monitoring decoupling. Also helps dial in hydration.

I think 73-77% is still relevant as a starting point. I see this chart referenced a lot also.

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My Strava | My Instagram | Summerville, SC | 35-39 AG | 4:41 (70.3), 10:05 (140.6) | 3x70.3, 1x140.6 | Cat 2 Cyclist

I agree! Been using this a lot too. I wonder if, now that bikes and positions have improved so much, if the numbers in that table are still 100% reliable. I think bike splits have become 10-15 mins faster over the last 10 years for AGs, at the same watts .. just a thought..

Watts and IF don’t care how fast you are going…

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My Strava | My Instagram | Summerville, SC | 35-39 AG | 4:41 (70.3), 10:05 (140.6) | 3x70.3, 1x140.6 | Cat 2 Cyclist

No, but you can always hold slightly more watts for less time, or slightly less watts for more time.

So time is a critical input. And since distance is fixed... Speed is implied.

So time is a critical input. And since distance is fixed... Speed is implied.//

Thanks for mentioning this important factor in the equation. Just like in swimming, there is a metabolic cost for each and every minute you swim longer than your competition. So it is with cycling too. In my day, a 5 hour ironman ride was the state of the art, and now that has gone down to 4 hours. There is a lot of extra eating and drinking that has to go on in that extra hour, and the metabolic cost is certainly going to show up in the run times too.

Reminds me of the hard heads that say power is power, never mind anything else when riding..

Estimated Bike Finish Time (i.e. how fast you are going) is literally the input side of your TSS table. Obviously it matters

I use a mix of lactate and testing in training. During the IM prep (last 12-14 weeks) I like to start 20 watts below my LT1, and do maybe 3x40 minutes in the TT position. If that feels good and I can hit 100 grams of carbs pr hour, next longer session I bump it up 5-10 watts. With 2 sessions of TT training around IM pace a week, it gives me around 20 sessions in the build up - to hit the right intensity. I try to get 2 sessions with 4 hours of specific intensity before the race - to get a feel for going fast and hitting my nutrition.

I coach some athletes without access to lactate - but it's almost the same thing. When they go too hard in training (they almost always do at some point in the build) we know they hit above target. Also X x 30 minutes starting conservative and then adding 10 watts every interval, you can almost feel where your limit is.

To make sure - try to swim hard in the morning, bike 5 hours including 4x50 minutes @ racepace and then run your long run the day after. How did the run feel? If it takes more than 4-5k to feel "normal," then you went too hard on the bike the day before (or didn't fuel enough during or after the bike).

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Long Distance PB: 8:25
Instagram: larsschmidttri

I would say that a good way of testing if you're in the right ballpark is 1-1.5 hour at goal pace at the end of a long ride and seeing how your body responds and if you have any HR drift.

This is the answer. It's not fun because it involves doing very hard training sessions (which you should be doing anyways if you're looking at setting opportunities IM pace).

Going off FTP (especially from a ramp or 20min test) amd Training Peaks TSS (which is calculated off FTP is going to have divergent results. Someone doing 1h Zwift workouts everyday are going to absolutely explode. Their anaerobic strength will skew the FTP result upwards and they'll set it at a pace far too high. Likewise someone who only does 4h Z2 rides and 'doesn't need speedwork' will have an artificially low FTP (especially in a ramp test) and leave a lot of pace on the table.

Ultimately you can guess within a 40-50 watt range, but until you get it there and start trying long hard efforts it's just guesswork.

I'm not understanding your question, especially when you acknowledge anticipated time is a key input. If you're 15 minutes faster, move down a row. For the same TSS target, you roughly move to the right 1 column (or increase power by 0.01 IF).

I don't see the difference between 0.72 and 0.73 or a drop in time of ~5% necessitating a significant change in TSS target. The YMMV aspect of that chart and the uncertainty in determining what FTP to base it on is much much much bigger than the bike tech impact.

I have personally determined race day target power from RPE and power on long rides. That said, I've probably over-biked in all 3 of my IMs based on my run performance compared to open marathon performance (~+30 minutes vs +15 rule of thumb), despite targeting the low end of IF on that chart. A combination of race excitement + an overestimated FTP.

Just remember that HR drift could also be a sign of dehydration and not overpacing :)

That's why I like the longer run the day after, to make sure I'm good.

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Long Distance PB: 8:25
Instagram: larsschmidttri

Good point!

I think that's because the AG ranks suck at managing bike effort during the race (myself included). After the taper, it's way too easy to over-push for the first 75% of an IM and the difference between +40' IM run and a +15' IM run is a knife edge.

OK, I just don't know anyone in AG ranks that actually does it. The pros seem able to do it, but not because they are pacing the bike better. If anything, they are doing more surges and riding harder overall. Perhaps total training volume or bike training volume are the big key factors.

I was curious about someone who won my AG at a recent IM in an outstanding time. Turns out they have been a world-class AGer, if that's a thing, for many years. Google shows me a calendar year 1:16 half vs their IM run time of 3:07, which was the fastest run split by a lot. 1:16 probably equates to very low 2:40s open marathon time, i.e. +25ish minutes. Could they have ridden 5min slower and run 10min faster? Maybe, I don't know, just doesn't seem anyone actually does it.

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Dimond Bikes Superfan

Both of these things can be true-the pros can be pacing the bike better and riding harder/surgy-er if their ability is high enough to handle it. Which is kind of borne out by their IM run times. I would imagine the biggest cause is that pro's need to be honest about their pace as a matter of income, and AG's have more of a tendency to overestimate their ability, which isn't evident until the run.

Not doubting the very good AG guy, but comparing a 1:16 half to a 9h IM is at best half as good a comparison as a marathon to an IM. It's equally possible that his endurance drops off such that his open time is closer to 2:50 which is only a 17min drop off.

It's a really hard concept to test because you can do 2-3 IM's in a year if you really press it, and it's much easier to bike too hard than bike too easy.

But if you're prepared for the last block of race specific training - you can "test" the bike maybe 3-4 times before the actual race. Yes, sometimes the truth is hard on the ego, but better failing in training than at the race. I guess if you never fail in training, you never know where the limit is. Then you taper - and think your can go from 70 grams pr hour and 240 watts in training to 110 gram pr hour and 260 watts in the race.

My best bike/run combo was in 2021. 10 days out from the race I did 2x50+2x30+2x20 minutes @ 8-10 watts higher than in the race on a flat course in the TT position with TT-helmet. The day after my long run was "good" - but not great like the week before. I knew I got the carbs before, during and after the ride = the power was just a bit too much. I ran exactly 20 minutes slower on the marathon in Almere (September), than a stand alone in April the same year. Almere was a bit hotter than the 10 degrees celcius marathon in April - which should be the 5 minutes longer than the "15 minutes rule"

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Long Distance PB: 8:25
Instagram: larsschmidttri

Lars how are you fueling your long run the day after the hard swim / long ride with IM power?

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http://www.tri-monkey.co.uk

Everyone's power curve / fatigue curve is a different shape, determined by training. Any correlation between say 20min power and IM power is not there because they're linked but because an experienced athlete tends to have more watts.
If you train a lot at 250 watts, you'll push the curve out and last longer at that power. Whether you last long enough to ride 180k and still have run legs depends on whether 250w was a realistic & specific training target. If 230w for six hours sounds doable, then 250 is probably a good target for training.
Rubbishing these ideas that you should only do intervals and a bunch of long 'recovery/base' spins then pull a percentage out of a hat and try to race it on the big day.

I fuel like in a race - around 50-60 grams pr hour. I run loops or have my girlfriend on a bike with bottles :)

I eat full breakfast before and I don’t try to limit carbs, as I think my limiter is my muscular Endurance and not my ability to ‘turn over energy’ <—- sorry I don’t know the english explanation/words

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Long Distance PB: 8:25
Instagram: larsschmidttri

Couldn't agree more with your first paragraph. I think the issue is that a lot of participants look at the 'last block of training' as the only block of training. People often expect a small miracle to occur on race day. A summer full of 1hr Zwift VO2 workouts leading to a 300w FTP ramp test does not mean you're able to do an IM bike at 250w. The problem of course is these 2x50+2x30+2x20 workouts are really hard. They prepare you well and give you a great idea of what to expect, but its SOOOOO much easier for people to just look at a graph.

. A summer full of 1hr Zwift VO2 workouts leading to a 300w FTP ramp test does not mean you're able to do an IM bike at 250w. The problem of course is these 2x50+2x30+2x20 workouts are really hard. They prepare you well and give you a great idea of what to expect, but its SOOOOO much easier for people to just look at a graph.

Had to flag an error in your math: 250 W translates to 0.83 IF on 300 W FTP. That's more like 70.3 intensity for 99% of AG athletes and is not a realistic IM IF.

2x50+ 2x 30 + 2 x20 @ IM power or just above is not hard at all if you really are in IM shape. Anyone struggling to complete this building into an IM really has to assess if their 5 hour power goal is realistic.