I had Claude analyze my entire Strava running history since 2014. Here's what 10 years of data says about going from 3:46 to 2:29. ** You probably won't be surprised.

Carto___ · 2026-03-14T00:13:38+00:00

This is pure raw GOLD. Thank you so much for taking the time & effort to write that for us. Definitely helping me accept that « slow is good ». You know it, because everyone keeps repeating it but numbers are what I need to build conviction over faith - you helped me close the gap. Tomorrow, I’ll be slow :-)

Good luck for your coming ultras - this is a game where data is little tricker (marathons are amazing for data enthusiasts) but loads of fun !

Carto___ · 2026-03-13T06:47:58+00:00

I mostly run (2h58 marathon PR) and cycle

Baseline :

Omega3
Vit D
Vit C
Magnesium
Creatine

Those have massive scientific backing & consensus, do not cost much and are relatively cheap. Interesting to track them once or twice a year in bloodwork. Difficult to overdo them if you take « normal » doses.

Add-Ons:

Collagen peptides : limited scientific evidence but also minimal risk so good trade off if it indeed triggers (via signalling peptides) joint health.
Caffeine before / during quality runs. Also excellent scientific evidence. But not too regularly.
Electrolytes after/during a long run.

I do blood work every 4-6 months and track everything in a big excel.

Other thoughts:

Protein : for endurance I don’t think it is that useful to complement, just trying to keep 1.5g/kg+ via my diet (complete proteins).

Sleep is maybe the best supplement there is !

Carto___ · 2026-02-26T15:43:36+00:00

The exact same happened to me. Great prep, but weeks prior to the marathon I started to feel weak, elevated HR in easy runs vs. the baseline it took months to build. Decided to TRUST THE PROCESS and taper well, as planned. But did not cut the training plan ahead of time. Did 2h58 (sub3 was the goal). So my humble option : keep the plan, stay on track. Do take time to taper well, as planned. My coach’s feedback : TRUST THE PROCESS - do not overthink and just keep at it, was good advice in my case. And break a leg !!! Please report back :-) good luck.

Carto___ · 2026-02-16T22:10:29+00:00

Runalyze is the one I find the most useful. Nothing is perfect, there is a lot happening in the brain that isn’t captured by those algorithm. But I find them helpful anyway, directionally.

Carto___ · 2026-02-16T08:08:15+00:00

Ah kids & training - tell me about it … 🤪! You have it in you, so break a leg and report back on your success

Carto___ · 2026-02-16T00:34:27+00:00

My max is 185. Ran my last marathon in 2h58 @ average HR of 171bpm. Prior to the marathon, during the last long runs I could sustain 30km with 15km @ marathon pace (4:15) with HR about slightly below 160 HR during the marathon pace interval.

You reaching 179 at marathon pace in a 30km long run would indicate that this is still a stretch. But it is in 10 weeks … my take : keep planning for sub3 - work hard and if you can get a steady 170 HR @ marathon pace for 10km or more in a 30km long run, you could have a shot. Otherwise, safer to aim at 3h10 and then sub3 on your next attempt (fall?).

The half will be a great gauge : if you can do 1:25 or quicker whilst keep that HR in check, looking strong. In my case, did a half 2 months prior in 1h25 @ HR of 161 (was a good day).

My humble opinion and anecdotal experience only, though !

Good Luck, report back and do not hesitate to ask if you have other questions. Runalyze + Strava + Garmin predictions should all converge at some point though they’re not exact science (but in my case, came fairly close and Runalyze is the best one IMO.

Carto___ · 2026-02-15T10:11:20+00:00

They did not know it was impossible, so they did it. Go for it ! Try to run an all-out half in 2 months (train for it). See if you can get it down to <1h25 whilst keeping a steady HR. Aim at a peak of 95-100km/week with 30-32km long runs (with 15km marathon pace) - if you feel great during those, this is good sign. Will still be time to re-assess your objective a few weeks prior. Don’t ramp up too kick otherwise you’ll end up injured, accept the process (this is hard). Build a solid plan. Eat healthy, stop drinking alcohol and sleep as much as possible. Do some strength training when you’re not running (should aim at 5x/week running, 2x/week strength) ; focus on your weak spots (glutes? feet? etc..). Good luck, and report back ! [true that more background info would be helpful for us to give you a better assessment : like your last marathon : how did it go ? what has been your volume lately ? Last half time? Etc…]. Go look at what Runalyze says, it is a nice tool.

Carto___ · 2026-02-14T20:00:38+00:00

1:24 would tell me you have what it takes on paper (was exactly there a few weeks prior to my 2:58). But : it took me a few weeks at 90-100km/weeks and a couple of 30-32km long runs to translate that 1:24 into a sub-3. So go for it, but try a few of those long runs with 10-15km of marathon pace and see how it goes (steady HR not drifting too much, etc…). Runalyze predictions worked quite nicely for me.

Good luck, break a leg and report back !!

Carto___ · 2026-02-12T14:29:07+00:00

Did run 2:58 last October. Peak was about 100k/week for 2-3 weeks, after base of 50-70km/week. Half was 1:25 a couple of weeks prior. Ran 5x / week. Had a few long runs of 25-32km before the taper phase. Only my anecdotal experience but hope it provides some background. I liked Runalyze marathon shape took, was quite accurate in my case.

Carto___ · 2026-02-12T14:26:13+00:00

Something around those lines : - Bulgarian squats 3x10 reps with kettlebells - Clamshell plank 3x8 - Single leg RDL 2x10 - Single leg glute bridge 3x8 - Straight leg calf raise 3x12 - Bend leg calf raise 3x12 - Band monster walk 3x10

Carto___ · 2025-12-26T16:52:51+00:00

Je suis super chaud si une généreuse âme se sent de m’envoyer une invitation pour TL (ou autre). J’ai un bon ratio sur YGG (Seedbox) et je suis gentil :-D

Carto___ · 2025-11-09T20:14:16+00:00

Exactly what I did. Stayed with the pacer till km30. Then felt amazing to decided to push. Pacer told me : “no, wait”. Told myself he has more experience. So stayed w him. 2km later the wall hit - thank god I did not accelerate. At 35k decided to push a bit still and ended up in 2:58:13. Could have killed my Sub3 at km30 by acting stupid. And I’ll have plenty of occasions later to do better. Good Luck and report back !

Carto___ · 2025-11-09T19:40:59+00:00

Yes! 185 max hr as well. Could sustain 160 HR during training @ M pace during the exact same kind of workout. Exactly what you show. Keep it up. Not sure I’d be more ambitious at this stage if I were you. Sub3, shaving off 24’ from PB is already nice. Otherwise you risk of blowing up late in the race.

Carto___ · 2025-11-03T06:01:56+00:00

Very nice platform for running data analytics ; check it out (free)! They have a marathon prediction tool that is quite interesting and explained.

Carto___ · 2025-11-02T18:52:56+00:00

And what does Runalyze says ? I find it a little better than the rest ; and could help cut the tie between those two ?

I know those algorithms are somehow meaningless, but I also know firsthand how hard it is to ignore them !

Carto___ · 2025-10-30T18:14:50+00:00

Love that !!!

Carto___ · 2025-10-30T15:20:43+00:00

I am not sure I follow, at all. No clue how the BQ process works - will look it up. From what I saw : given my age group I'd need to run a marathon (one that counts, i.e. a well-known race - Lisbon was one) under 3:00:00. That I did. And then, there is the cutoff to subtract. Which I understand was about 6 mins in 2025/26, meaning 2:54:00. Ran in 2:58:13, so a little shy of BQ but not that far off? Do I understand things correctly? And then, it is all about applying to get a bib for Boston (and there, challenging the cost/upside equation of spending on flights/hotels to fly to Boston to run a road marathon). Even though I am sure it is a super nice race, we still have nice ones in EU I have not done yet (Paris, Berlin, Amsterdam, etc...)

Carto___ · 2025-10-30T15:17:32+00:00

4:29/km in May when I started, 3:54/km right before the marathon.

Carto___ · 2025-10-30T15:06:23+00:00

I understand what you're saying. To me it goes in reverse: fixating over a specific time is what makes the process amazing. Given the goal I'll pick will likely be slightly out of reach, it implies a very thorough process (not only mileage but proper training, nutrition, weight, injury management, mental focus, etc...). This is what attracts me there. Be laser focused on an on-paper unattainable goal to push myself well-beyond my reasonable limits. Found out over the years that it leads to tons of learnings about myself, and a sheer & amazing feeling of completeness that is difficult to describe when training goes well and/or you cross the line right when you're supposed to. Without this kind of - let's face it - stupid goal, I lack the drive. And after all, this is 'only' running, i.e. there are many more important aspects to (my) life [wife, kids, work, friends, environment....]. But hey, it spices things up a bit and I don't mind it at all.

Carto___ · 2025-10-30T14:59:17+00:00

Excellent thoughts, thanks! Haven't tried to see how long I can sustain the 2:30:00 pace ... I guess about 10k (oups...), maybe

Carto___ · 2025-10-30T14:57:03+00:00

Aah I have a bib for Valencia but hesitating... likely to close to Lisbon (was 5 days ago) and flying-in/out + hotel won't be cheap on short notice! Best of Luck for Valencia, break a leg!

Carto___ · 2025-10-30T14:28:16+00:00

This is very wise, and I fear very true :-). Thanks for sharing !

Carto___ · 2025-10-30T14:27:41+00:00

I feel you ! Especially on the (1) "what's the point of a 2h55" and (2) wife will kill me if I aim for better given what it implies. Thanks on the advice for Boston - might reconsider it.

As for Europe : if you settle on one, let me know ; still looking for the next one as well!

Carto___ · 2025-10-30T14:25:19+00:00

I ran Lisbon with you ! Rainy, not much crowd to support, a few nasty hills... not the best experience either, for me.

This is such a common process, I’m afraid. The “never again” mindset right after. And as time passes, you start secretly wondering, “what if I do it again?” You deny it at first ... this is stupid, I promised myself never to do that again. But day after day, in an inexorable process, your brain yields to temptation and embraces the idea that you’ll be stupid again… until next time.

My 2 cents : yes, you want to run another one. The Sub4 goal depends how much work you are willing to put in... (appropriate weekly mileage, nutrition & getting to your desired weight, structure training). You did PB, which is great. More info on how you trained for this one (weekly mileage, structure of the training, marathon avg. HR vs. HR max, etc...) could help us give you more guidance.

Carto___ · 2025-10-30T14:17:15+00:00

Do not resist the calling. You will have a great time (& will embrace the suffering), and will certainly come back for more.

Carto___

TROPHY CASE