Whatever you do decide on doing, post back after the race. I'm very curious how it turns out if you decide your target race wattage on this tool.

I don't mind to do that at all. I figured that others could maybe benefit from the info so that's why I made a thread versus just PM'ing a couple of ST gurus.

I rented a Powertap wheel at Muncie and the numbers/times from BBS and actual were very close. I had never raced with a PM or used BBS before. I had an okay run, but was admittedly a little slower than I had hoped for. I do think that heat and rollers played a bit of a factor there. Muncie bike was just under 2:28 and my run was 1:35. As we all know, a half and a full IM are two different animals, though...

Now I own a PT wheel and I will cover it for IM Chattanooga. I am renting an 808 front.

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

 
So this is what BBS suggests I ride for a NP model of 75%. This is the old version, not 116mi. Seems like decent speed (for me) without much work. FTP is 178 ish. Seems too easy.. but then, I'm tapering off of JonnyO coaching... :OP
Race OverviewCourseIronman ChattanoogaDistance181.02 kmTime 5 hours 49 mins 27 secsAvg. Speed31.08 kphAvg. Power127.94 wattsNormalized Power®130.37 wattsVariability Index1.02Intensity Factor®0.74Training Stress Score®321Watts/Kg2.13Avg. Yaw9.50 °BikeP2Public Link bestbikesplit.com/public-race?r=605Cheat Sheet bestbikesplit.com/watt-hin

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formerly but still a Run Snail...

I just updated to the 116 mile version today; I had been using the 112 mile one prior. I'd like to ride a higher IF, but I really want to set up for a good run (I'm not saying that you won't at 0.74). I'm wondering if I'm being overly cautious and that is a big part of why I posted here. Muncie that I mentioned above was right at 0.8 and 201W NP.

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

oh, my pic. didn't show up.
well you're a zillion times faster than me on the run, so you behave on the bike.... and I'll have fun - just kidding...

I recently did an iron swim/bike at 70% FTP, and felt like I had legs after. I'll probably behave myself, especially since we have all of those extra miles :OP
I'm interested in what others on here have to say too.

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formerly but still a Run Snail...

Is the extra four miles at the beginning or the end of the bike? Was that ever clarified??? ;)

Since I'm not certain I better play it safe and stick to 0.70 as to not mess up my run...

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

We have near identical numbers (245W & 155lbs). I used BBS for IMWI planning. I hit the AP target and was a little high on the NP but still below 75%. (I was very disciplined, but w/o a compact crank there was no way I could hit the projected variability index.) The BBS projection was only 90 seconds faster than my actual moving time (i.e. accurate to one half of one percent). The BBS cheat sheet is a great guide for different situations/terrains. It set me up for a very good run on the run fitness that I took into the race.

Saying whether it will work for you though is hard without more context. Biggest key: it should still feel easy 5 hours into the bike.

Side note: Assuming other inputs are similar, IM CHOO 116 mile is ~4 minutes faster than IM WI 112 mile. Good luck!

I had a really nifty plan to ride a certain wattage and low VI at IMWI. Didn't happen. I let myself get sucked in to riding harder up the hills early on when following the leader in my AG. I figured hell, he's a 4x veteran on this course if he's not going slow up the early hills, then screw it, I'm not either. Worked out OK, but I wonder if I gave up some time be riding a little less even on pacing. It was my 1st IM so I can't really say for sure if it hurt my run, having never run more than 13.1 off the bike.

All I'm saying is ... good luck with that. I'm nailed pacing on 70.3's where you're riding a lot harder. But when things slow down it's harder to back off on all those climbs and rolling hills.

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TrainingBible Coaching
http://www.trainingbible.com

I think that number is a good conservative plan. Keep in mind that if you last build went well and you've tapered, you FTP might be a little higher, so don;t be afraid to ride just a tad higher. Also don't be surprised if depending on wind, it takes you just a little longer than predicted. Wind can change over 5+ hours.... and it's often not favorable.

My reminder on the run is to go out slow. Go out in a 7:30... no faster, maybe even a tad slower in mile 1-2. Then lock it in. It will get harder, but if you don't start cramping up, I think you can battle it out and maintain it to the end and even speed up a bit the last 5k. I didn't believe you could do negative splits, but looking at my limiting factors and how my pace slowed less that it felt like it dropped, I think it's very possible. But maybe I also over biked a little and under performed on the run a little too. Hard to say for sure. I know I'd love a "do-over" on those first 3 miles.

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TrainingBible Coaching
http://www.trainingbible.com

I used BBS for IMWI and it's almost spot on. Definitely within 90 seconds of accurate.

I'm sticking with .70 IF as well for IMCHOO (first IM). I'm ~158lb and 280W FTP. Below is a screenshot of my bestbikesplit (happy to compare notes afterward). I redid my bestbikesplit based on the longer course (uploaded it as a public course on the site)



http://www.bestbikesplit.com/public-race?r=8633

edit: oh on review, I see you used the course file uploaded

22.4 mph on 196 watts? Seems fast for that number of watts. What did you put in for CdA and rolling resistance?

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Proud Member of Chris McDonald's 2018 Big Sexy Race Team "That which doesn't kill me, will only make me stronger"
Blog-Twitter-Instagram-Race Reports - 2018 Races: IM Florida 70.3, IM Raleigh 70.3, IM 70.3 World Championships - South Africa, IM North Carolina 70.3

Hey guys sorry for the delay on a verified course for this. I was told they changed it up a bit in some sections and will update it tomorrow (still 116 miles...) Have you tried the TSS target model for running well off the bike. A couple athletes used this method at St. Criox and IM MT with really good results (good runs off the bike that is).

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Founder: BestBikeSplit
Amazonian

I used BBS for IMMT and was within 1.5%. I use it for training to calibrate the coefficients and you get pretty good results. I think it is also good for setting realistic long term goals for IM distance races.

Seems reasonable to me.....I averaged 23 mph on 195w @ Racine. Guess it depends on rider size, etc.

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Chicago Cubs - 2016 WORLD SERIES Champions!!!!

"If ever the time should come, when vain and aspiring men shall possess the highest seats in government, our country will stand in need of its experienced patriots to prevent its ruin." - Samuel Adams

I averaged 22.71 at Muncie this year on 190W so, yeah, that seems legit to me, too.

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

22.2 on 219AP... on a very hilly course. Very possible for a smaller rider. How close is is for your other races? Have you gone back and plugged in the same average watts?

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TrainingBible Coaching
http://www.trainingbible.com

That sounds solid to me. Thanks for your input. I was already thinking about going out easy the first couple of miles, even if I'm feeling great. I agree that 7:30-7:45 would be good just to get a feel for where my legs are at. Basically all of my run training, long runs, etc. leading up to this has been in the 7:20 range which is my "all day" pace. I love to negative split (who doesn't?) so that will be the goal. I hope to start out conservative and just keep turning the screws a little tighter mile by mile.

To your more recent post, Muncie was the only time I've used power so that is the only data I have to go by.

Also, I enjoyed reading your recent race report, congrats! Unfortunately, I'm a slow swimmer so I don't have to worry about KQ and such!

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

Went back and looked at your original post.....we are clearly in the same ballpark as it pertains to FTP, weight, etc. (I'm a few lbs under you @ 150).

Not familiar with the Choo course, but know it is supposed to be hilly. If it is similar to IMWI, your numbers look pretty good. I road 180NP @ Wisconsin and went 5:27. BSS had me @ 180w for 20mph avg, but the wind was lighter than my model (5 mph vs 10 in the model). I'm using my NP because I coasted quite a bit on the hills, so my avg power was quite a bit lower (155).

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Chicago Cubs - 2016 WORLD SERIES Champions!!!!

"If ever the time should come, when vain and aspiring men shall possess the highest seats in government, our country will stand in need of its experienced patriots to prevent its ruin." - Samuel Adams

It's not IF or NP that you should be looking at, but rather TSS. You should budget 250-270 TSS for the bike leg.

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AndyF
bike geek

Hmmm... Okay. How can you forecast that? I rode a century three weeks ago (no aero gear) at 172W (182W NP, .0724 IF) that netted a TSS of 255.7. Can I assume that adding 16 more miles to that I would still be in that 250-270 TSS range? By looking at the HR and power data from my ride you can clearly see that I started pushing harder the last 40 minutes of the ride and that is where the NP (and TSS I assume?) creeped up. I obviously wouldn't do that during an IM...

http://connect.garmin.com/activity/578735995

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

You might ask MrCooper to add that as a constraint in BBS. He's really keen to do anything to improve BBS, I'm sure!

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AndyF
bike geek

Just wondering what IF are you targeting on your long rides? I'm doing IMFL and I'm 14 weeks in. All of my long rides so far I've done IF .73 and 7-8 of those were > 100mi. I'm also 154 lbs and my FTP is 248 though I haven't tested in a while.

I'm using BBS to project my race time and I should be able to go 5:07 at IF .73. I actually rode a flat 112 TT at those watts and did exactly 5:07 with race wheels (no disc) and road helmet and kit. I also back tested BBS on my last 70.3 race this weekend where I rode .81 and went 2:26 which was 3 seconds faster than the BBS race plan. Conclusion, I believe BBS is legit :)

I'm considering "sand bagging" the bike and ride .70 or .71 during my race just because this is my first IM and my first marathon so frankly I'm a little creeped out by it. I do think it's a good idea to train at a higher IF though. Is there anything to gain by going even higher e.g. .75 in training?

I just saw your post. I am new to BBS so I'll have to plead ignorance here so I do apologize. Where is the "TSS target model"? I am currently only signed up for the free/trial account if that matters in regard to my question. Also, are you saying that there will be an updated Chattanooga course listed today? BBS has my current projected TSS at 274 it appears.

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

It's in the race plan screen:

Thanks. I see where it is now. It looks like I can't access it since I only have a trial/free account. I'm thinking it's probably worth $20 since I don't do an IM that often...

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

Use this coupon (25% off) BBSTREK

On it. Thanks!

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

The problem is, if you don't stick to the plan or the model is off, your TSS will be higher.

I had a goal of 260 at IMWI and rode 285TSS because I rode a little hard on the hills so my VI was high.

I'd love to know how close I have been if I paced it perfectly to their model.


Too bad you can't work the model backwards, and put in your AP, NP and and have it spit out a time based on less than ideal pacing... just to benchmark the aero model and then to see how much faster you would have gone if paced better.

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TrainingBible Coaching
http://www.trainingbible.com

Whew saw you post last night and got a little worried, didn't have time to look into it till now. Glad to see that based on some others feedback it doesn't sound *too* off.

I left the CdA and rolling resistance values as the defaults. This is on a P3C with with all aero goodies.

With an IF of .70 I have a projected TSS of ~250 which seems right about inline with where I want to be.

TSS is in the system. It's just on the paid version...

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Founder: BestBikeSplit
Amazonian

In the works :) Well taking actual ride file in and doing some different metrics than garmin, golden c, etc (don't want to recreate the wheel).

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Founder: BestBikeSplit
Amazonian

Getting a better course up this evening will post here when I get it on the system. Most pros tend to stick to the cheat sheet. You can also do some adjustment on it try at various 10 watt increments up and down from target and come up with a baseline with plus and minus watts for various conditions. We used that tactic for a couple pros, so they could get a feel out on the course then adjust accordingly.

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Founder: BestBikeSplit
Amazonian

Awesome. I look forward to it. I went ahead and subscribed to take advantage of the TSS model.

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

This probably needs to be in another thread but I am set up for Chat as well.

When it says get weather, it starts the ride at 53 degrees. Does the model take into account rising temps or should an average be put in there?

Also I have it set on poor roads. What is everyone setting their road conditions for to get as close as possible to accurate with correct pacing?

We are working on taking in up to 8 hours of forecast data for now I would use the average. I know it is a big deal at windy races (especially for coastal races). I usually say choose the road conditions you see across the majority of the race. For most it would be average (poor would be mostly cracked or light chip seal for most of the race).

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Founder: BestBikeSplit
Amazonian

I have it set on poor, wind 10mph from the west, and it still says I can ride 5:01 for 116 on 240NP, 274 TSS, and I'm 6'3" 80kg. For reference, I did a lap of the course a few weeks ago (out stick, one loop, in stick) at 21mph on 240NP with no aero toys, stopping at lights, stop signs, taking a couple wrong turns, flat tire, etc. 22mph with toys sounds more reasonable, 23mph no way.

FWIW it predicted my Muncie and Steelhead times about 3 minutes faster than I went. I must be a human sail.

We do find that many triathletes (including me) tend to over estimate how aero they are. Especially in full IM setup. My hope is to be able to fine tune the CdA variables much easier with actual ride test data soon. Testing with TFR data to see how close our method comes to the wind tunnel and velodrome testing. If I had spare development time it could go much faster. Right now though time to make sure our course is good for you guys.

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Founder: BestBikeSplit
Amazonian

I'm riding a 2014 Speed Concept but selected "standard TT/Tri bike" and "aerobars/advanced." I changed the "advanced" to "midpack" and it brought it down to 5:13 which seems more reasonable. Anyway you guys do a fine job and I know it's not perfect but it's fun to play with.

Sorry for the delay finally got a "verified" course in the system, meaning it follows the correct roads though. I think I start it a bit out of transition and end a bit before so 115.9 miles :)
It's called
2014 Ironman Chattanooga (update)

and you can filter on verified courses. Working on speeding up the queries on the courses page.

http://www.bestbikesplit.com/public-course?c=10271

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Founder: BestBikeSplit
Amazonian

I added the updated verified course. Thank you for that. I have a question on the TSS model. How should one determine what TSS to use? Is there any rhyme or reason to it such as a stronger runner should be able to run off of a higher TSS, etc.? Or is it typically pretty much an even trade off. Bike easier/run faster, bike harder/run slower (in theory)? I think that the range AndyF stated was 250-270.

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

Here's a nice article to read: http://home.trainingpeaks.com/...-meter-in-an-ironman

Thanks Sp1ke. I was about to post the same thing :)

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Founder: BestBikeSplit
Amazonian

Thank you for the link. I will read it now. I realize that there are books for all of the questions I am asking since I have seen posts about them many times. Since I just got my power meter very recently I don't have time to go that route this time so that is why I'm just trying to get the Cliffs Notes. I will look into the books once this IM is finished.

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

To summarize, if you are:

a) beginner, unsure of your run then target TSS 249 - 262
b) decent athlete and trained consistently 260 - 286
c) the real Starky then 281 - 309

I actually just read that article and looked at the chart earlier this week. I think I was just researching so much that I was doing laps around myself, but now I will stop! I believe I've found my number/s...

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

I'm also going to work on many more support docs in the off season as well as some new automated features to help each athlete fine tune input parameters for specific environmental conditions (racing in hot temps / high humidity / different altitudes etc). The current model takes all of these into consideration for the physics but expand it to the physiological side as well.

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Founder: BestBikeSplit
Amazonian

Couple of questions on inputs. For example how do you determine the difference on position? You could get drastically different results in output on that single variable alone. Further explaination or guidance there would be helpful.

Yes that is the biggest source of variation. We are working on a way to hone the number in much better, but in the mean time you can use a previous race and adjust the 0 yaw value (which will calculate drag at other yaw angles) so that the average power (not normalized power) match your average power and the times match closely to what you actually did. While this is of course not perfect our users who do this tend to get very good results. Going forward we have what I think is a slick solution that in testing has gotten really really good results. I wanted to have it out this month, but Interbike threw a week delay in my time-table.

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Founder: BestBikeSplit
Amazonian

I dialled in some figures for the new Chatt course. My estimated Ironman Canada was pretty accurate, within 2 minutes. I adjusted my NP to match my actual NP at IMC and that got the figures a touch closer.

Having done that I used exactly the same setup for bike and rider, swapped out the course to Chattanooga and made the course 'Average Suburban' or whatever that option is (I used Mountainous for Whistler).

The Chatt Course is around 8 or 9km longer than Whistler but I am getting around 12 minutes faster than Whistler. Happy with that obviously but it seems like a lot. Are others getting figures that seem solid?

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https://www.pbandjcoaching.com
https://www.thisbigroadtrip.com

Should be a lot less climbing over the course.

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Founder: BestBikeSplit
Amazonian

No kidding, just didn't think it would make that much difference bearing in mind there is a lot less downhill too. More than happy though ... I'll hold you to it! :)

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https://www.pbandjcoaching.com
https://www.thisbigroadtrip.com

Haha crap pressure is on now!

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Founder: BestBikeSplit
Amazonian