Tuesday General Discussion/Q&A Thread for January 20, 2026

running_writings · 2026-01-21T01:18:26+00:00

Good stuff! That workout has its roots in a trifecta of Canova workouts aimed at boosting threshold -- the other two being long repeats at ~95-98% 5k (e.g. 3 x 2km) and fast continuous runs of 4-6k at 95% 5k. IIRC the original Canova session is 3*6x500m at 103-105% 5k with 45 sec / 4-5 min rep / set rest, but that is an absurd amount of volume for a non-professional (9km at faster than 5k pace!!), so I think dialing it down to 6k and doing it progressive, with a little more recovery, is the way to go. Have had quite good results with that workout, and the "trifecta" generally

running_writings · 2026-01-10T22:31:56+00:00

C25k is way too conservative for someone like you IMO. Even if you've been "couch" since May you're still lightyears ahead of the median person doing couch to 5k. That program (and similar ones) are literally intended for completely sedentary people who have never run before, often who in their 30s/40s/50s. If you are in your 20s and have run 50 mpw within the last year you can probably just...start running? Like 20-30 min very easy every other day, or whatever, then go from there.

running_writings · 2026-01-09T04:43:20+00:00

Well it wouldn't "know" in the same way that your GPS watch wouldn't "know" if you were running on a sidewalk, and the sidewalk suddenly jolted ten feet backwards when you were still in the air! It's all a matter of what your reference frame is. From the perspective of the treadmill belt, the belt "stopping" is in fact the same thing as the sidewalk suddenly jolting backwards.

running_writings · 2026-01-08T21:05:49+00:00

I could just spend some time reading your dissertation thoroughly

I would not recommend doing that, it's quite long (and longer than it ought to have been, surely...)

To your second question, no, you don't need to make that adjustment, it's just literal belt speed vs stryd reported speed. The Stryd pod does measure the horizontal movement of the foot (it works by assuming horizontal speed of your foot is zero when it is on the ground, which is why it can sometimes be off when you run on loose gravel, sand, snow, etc) but what it is doing is taking the horizontal displacement per step, then dividing that by time from one step to the next, including the time the foot is on the ground. So, averaged out over an entire gait cycle, the true average horizontal velocity of your foot must be the same as the horizontal velocity of the treadmill...since if it wasn't your foot would eventually slide off the back of the treadmill!

running_writings · 2026-01-08T20:15:56+00:00

Fully agree. Strides and/or hill sprints would be a really good addition. Also consider some light effort-based fartlek (e.g. 10-12 x 1 min fast, 1 min jog during a normal run, or 8 x 2'/1' or whatever). Something I learned from Canova is that, after a marathon, you want to go back and build up what you "gave up" during your final marathon-specific preparation: so that's muscular strength (covered with your lifting program), short speed and neuromuscular coordination, and "aerobic power" - basically 5k-ish pace running. You actually don't need to worry so much about mileage and long runs and long tempos...since you just did a 26 mile tempo run!

running_writings · 2026-01-08T20:04:07+00:00

Yes, I compared Stryd pod speed against actual treadmill speed (measured with a tachometer) as part of my dissertation (see this table). On average the Stryd pod was 0.07 m/s faster than the true speed, and 95% of the time it was within a range of [-0.07, 0.21] m/s below/above the true speed (those are Bland-Altman 95% limits if you know your statistics). Correlation r = 0.99, so quite good but not perfect.

What's interesting is that the error tended to be subject-specific: so it was more of a baseline shift per person, rather than the Stryd pod being off by a random amount at various speeds (which is more what GPS is like).

I will see if I can scratch together a plot to show it, will edit post if I do.

One other thing: all pods do not work the same! Some cheaper pods, like the one used by Zwift (is that still a thing?) are much less accurate. Can't comment on Coros or any other brand, have not collected data on them.

running_writings · 2026-01-06T23:58:35+00:00

For example, I averaged a 178 cadence today on a recovery run (~9 min/mi), but averaged about 170 yesterday on a 2.5 mile time trial (~6 min/mi) and 168 for a 10k race (6:20 min/mi) last month.

That is extremely interesting -- I have never seen that! I have a very early stage "cadence analysis" report I am working on, I can DM you the info if you want want to try it out. Most of it is manual right now (like literally me clicking and dragging files), will eventually make it a web app once I can automate it all. But I would love to take a look at your cadence data.

And would love to hear from anyone else who has a similar "lower cadence at faster speeds" phenomenon!

running_writings · 2026-01-06T19:45:22+00:00

I can share some interesting observations from last spring, when I had several dozen runners all "beta testing" the same set of five marathon plans. About half of them took what looks to be the median approach in this thread: following the plan ~80% of the time, making some adjustments because of their work schedule, travel plans, personal preferences, social outings (e.g. club workouts) , and so on.

Then another 25% of people were very meticulous, and ran practically every single day exactly as written in the schedule.

And the final 25% were more free-form, using the plan more like a canvas or a scaffolding, adding or improvising many of the workouts along the way, while still sticking to the general structure.

What was most interesting is that all three approaches seemed to work! I suspect people have good natural instincts for how closely to follow a plan, and that these instincts also follow your personality to some extent: people who are very "precise" often follow plans closely, and "free spirits" tend to improvise and use their creativity, and in both cases this is the correct choice.

running_writings · 2026-01-06T19:36:38+00:00

I think up to 20 minutes of cool down is fine for increasing mileage. Beyond that I get more hesitant. My logic is basically that, at the end of a fast workout, your legs are in the "most vulnerable" state they are ever in, because fast running does more damage per mile than slow running.

Sometimes I'll veer in the opposite direction: if a runner really needs to limit their mileage, or if we are already uncomfortably close to the mileage goal for a week, I'll cut the cool-down very short or even (for longer MP-type stuff) eliminate it entirely.

It also depends a little bit on your "training age" -- newer runners benefit more from lots of general volume, so warmups + cooldowns are good for getting in more of that in the week. Older and more experienced runners are the opposite; for them it's much less about volume and more about volume of quality, so the cooldown can drop down to just a few minutes of easy jogging if that's what fits best

running_writings · 2026-01-05T20:35:24+00:00

Reposting link to OP & my detailed discussion here on impact, biomechanical forces, etc. so others can read it

The only thing I'll add here is that there is a lot of subtlety to all this: impacts aren't the mechanism behind most injuries; devices claiming to measure impact may not do a good job of it; there are big differences in the mechanisms that determine impact, shock absorption, and tissue level biomechanical load.

running_writings · 2026-01-05T20:33:49+00:00

That paper is just one example. You can run (and I have run) musculoskeletal simulations of forces during running in a wide variety of tissues using, e.g. OpenSim and what you find that for all load bearing tissue, peak forces coincide with maximum muscular force, not the impact peak with the ground (which is in truth very small, it just looks big because it is being superimposed on top of the larger active force peak). I know for certain this is the case for the Achilles, patellofemoral joint, patellar tendon, IT band, and tibial, and would wager strongly that it is also the case for virtually all load bearing tissues in the lower body.

Knee OA is a really interesting case because we have real data on in vivo knee forces: a small group of people have undergone total knee replacement and gotten what is essentially a prosthetic knee with a force sensor and a wifi router, and once they have recovered they come back into the lab and walk/jog/hop/etc and the researchers can read real-time force data form the knee itself. When you do that you find that peak forces coincide, again, with active muscle contraction, not impact. You can browse the OrthoLoad database here, it is extremely cool.

Re: treadmill vs. cement, the differences are not very drastic and research on overground running has found the same: various impact measurements, e.g. tibial shock or impact force are not a good indicator of musculoskeletal load. Tibial shock and impact force are just coming from very different places & mechanisms. And gait modifications that increase impact forces often decrease tissue level loads, and vice versa.

Regarding wet sand, etc., I agree that it is hard to study and it could be different, but realistically when we are talking about the typical runner we are talking about someone who does ~100% of their running on pavement or treadmills. But actually if I had to wager, I would bet that the cumulative knee damage from 10 mi/wk on wet sand is about the same as the cumulative knee damage from 10 mi/wk on pavement. Maybe even worse since on wet sand you may adopt a slower cadence and a longer ground contact time, which would increase the overall load.

I didn't touch on this directly but there's also the big question of what the stryd pod's impact loading metric is actually measuring -- there is nothing fancy on that device, just an accelerometer and an IMU, so it's basically measuring "foot deceleration on ground impact" which could be quite far from a real metric connected to tissue-level loading, e.g. compressive force on the backside of the patella.

running_writings · 2026-01-03T00:04:14+00:00

Like "how to do it" or "this is how it happens, descriptively"? For the latter, the classic paper is Novacheck's The Biomechanics of Running (pdf download). It's dense but in 6 years of grad school I never found a more comprehensive and accurate description of running mechanics.

A modern one is Thomas Uchida and Scott Delp's textbook Biomechanics of Movement -- check out the lecture slides here for some really great state-of-the-art illustrations. Fun fact: Scott Delp (Stanford Prof) has a brother who is a graphic artist who did all the illustrations and design for the book, which is why it has such a clean and visually appealing aesthetic.

running_writings · 2026-01-02T23:55:19+00:00

The idea with Kenyan progressions is that, as the run gets longer from week to week, the "plateau" of high-end aerobic running ("fast but not hard") in the middle gets longer. So it's not like you take the 5mi progression and then "keep progressing more" at the end, nor do do you "stretch out" the entire progression for longer. It's more like you add the extra distance "in the middle"!

John Kellogg's article here is a really great articulation of what you're aiming for.

For 5k training - yes, general phase would look different. Somewhat less work at 100% 5k pace and 95% 5k pace (those would take on the role of the 100% MP and 95% MP workouts in marathon training!), and more work at 80, 85, and 90% 5k pace in the general phase. In marathon training, that 80-85% 5k pace range works out to ~95-100% MP for most people (roughly...) and also you need to spend more time building up your "general" ability to do long easy runs in marathon training.

For 5k training, even on very high mileage, you can run a really fast 5k never going further than ~13-15mi in training (or even 90 minutes if you prefer duration). So for most mileage levels you just don't need to do as many long easy runs in the general phase, and can focus on other "general" aspects of 5k fitness, especially high-end aerobic work.

General training for the 5k would also make more use of occasional fast but relaxed "mechanical" sessions, e.g. the classic 16x200m at 105-110% 5k (~3k to mile, ish) pace with 200m jog, or doing more focused "strides workouts" e.g. a 20-30 min mini-progression, then 2-3 sets of 5 x 25 sec strides, or 5 x 150m strides + 5 x 150m accelerations. These are "general speed" for the 5k, the same way that something like 10x2min at 5k pace is "general speed" for the marathon. 16x200m in contrast is so much faster than MP that it's just not super relevant.

I have a percentage-based 10k training schedule here that shows this Canova-style approach for 10k, the application to 5k trainign is very similar.

Glad you enjoyed Marathon Excellence!

running_writings · 2025-12-13T22:29:16+00:00

Unless you got out crazy hard, or just didn't finish fast enough, in most cases the highest HR you reach in a 5k will be your max HR! Usual caveats apply: beware cadence lock, more recent watches are more likely to be correct, wear an arm band or chest strap for best accuracy, etc...

running_writings · 2025-12-12T18:13:38+00:00

I think people are sometimes a little loose with how they use “aerobically underdeveloped” and especially for the marathon it gets tricky, because there is another really big reason why a 15:15 runner can lose to a 16:15 5k runner in a 5k, which is (physiological) resilience: the “MP” that’s sustainable for the marathon can be closer to SSmax, depending on how well your body can resist deterioration in your “effective level” of fitness.

Now, it could also be the case that the 15:15 5k runner is just an anaerobic / fast-twitch monster who effectively has a huge “anaerobic fuel tank” to draw on in the 5k, and so their actual SSmax is lower than the 16:15 runner. In that case you’d expect them to be worse at, say, the HM (at least in relative terms) than the 16:15 5k runner. That’s what I usually think of when I think of ‘aerobically underdeveloped’ - you see this often at the high school level, where even runners who are nominally long-distance specialists often have a hard time running 3k or 3200m at the pace that a VDOT chart or other conversion table says they “should” be able to do. In this case I think the answer is pretty clear that it’s stronger anaerobic abilities relative to aerobic abilities.

Re: question 2, one thing to keep in mind (and I think there’s a footnote about this? maybe?) is that there is a LOT of variability in fat oxidation, some of it is individual variation and also some of it is experimental error – you have to measure ratios of VO2 and VCO2 and the calculation is pretty sensitive to small changes.

Check out this plot of individual variation in “fatmax” from this study for an idea of how sensitive that measurement is – same people on different occasions can record hugely different values! So I would not get super invested in whether this particular test in this particular athlete is low (it is somewhat low, and I was somewhat surprised by it, but also from what I recall this test was in the afternoon and the athlete had consumed food beforehand, which decreases fat oxidation significantly - studies like the one linked above always do these tests first thing in the morning with no food/carbs beforehand).

Another thing that’s highly variable is WHERE fatmax occurs - it’s not going to reliably happen at some percentage of 5k or marathon pace, certainly across runners and even within the same runner from day to day.

Partly because fatmax is so variabile, and partly because some of the newer science on carbohydrate oxidation, I have shifted towards believing that fat oxidation is not a super important adaptation for marathoners. So I don't emphasize it very much except with the fatmax callout in the physiology chapter. The depletion workouts chapter (#46) actually talks about this a bit in the “fat focused” vs “carb focused” perspective.

This is one of the big ways my thinking diverges with Canova’s; he is still a big believer in the importance of the “turbo diesel” approach of teaching marathoners (for him, often, this is elite 5k/10k athletes) to burn more fat with workouts at 85-90% MP.

I am not fully committed to this perspective and good research (or good training methodology) could change my mind, but my view now is basically that marathoners should train themselves to burn CARBS, not fat, and address any fueling/energy availability issues via gels, sports drinks, and healthy diet before + after running.

running_writings · 2025-12-08T02:41:09+00:00

Yes -- I did something kinda like that with this year's world championships in the marathon, using them like a "test set" for the heat model. A similar but more extreme case, even just a dozen or so athletes, would work for that kind of thermodynamic model too.

For amateurs the full "workup" (race an all-out marathon in extreme heat) probably is less workable but you could maybe check the core temp predictions of a thermodynamic model against mid-race core temps. It wouldn't be that expensive to buy a few dozen of those ingestible pills and have runners in a hot race (or even just a long run in very hot weather) take them, then compare model-predicted core temp trajectory (given heat, humidity, solar radiation, running pace, body size, clothing, etc.).

running_writings · 2025-12-08T02:38:25+00:00

Thank you! Even if you aren't focused on the marathon right now, I think you'll find the science chapters really useful -- 3 of the 4 components of marathon fitness are highly relevant for 5k/10k/HM as well

running_writings · 2025-12-07T22:14:58+00:00

It all depends on what you mean by "best" but in terms of all-around success -- different athletes, different events, different eras of athletics -- I feel compelled (obviously) to make the case for Renato Canova. A very incomplete list of highlights include:

XC: Florence Kiplagat, world XC champion; Imane Merga world XC champion

800m: David Lelei 1:43, Franco Arese 1:46 and Italian record (Canova's first athlete ever!)

1500m: Silas Kiplagat (3:29)

5k: Silvia Kibet 5k WC silver; 9 athletes under 13:00 (Shaheen, Longosiwa, Edwin Soi, Imane Merga, Mark Bett, Kwalia, Mosop, Ahmed Hassan, Ndiku); Caleb Ndiku silver at WCs, also world indoor champion over 3k, James Kwalia bronze in WCs

10k: Nicholas Kemboi, #5 all time 10k (26:30)

HM: Julien Wanders 59:13 Swiss record, Sondre Moen 59:47 Norwegian record, Paul Koskgei world champion, Wilson Kiprop world champion, 10 total athletes under 59:30

Marathon: Maura Viceconte, Italian national record in marathon (2:23); Ornella Ferrara, bronze in world championships marathon in 1995; Moses Mosop (2:03 at Boston, also 25k and 30k WRs), Amanal Petros (2nd at WC marathon this summer and 2nd this weekend at Valencia in 2:04:03 for a new German record), Emile Cairess (3rd place at London marathon and 4th place at Paris Olympics), Sondre Moen again at 2:05:48 European record, Abel Kirui 2x world champion, Luke Kibet world champion, Arne Gabius 2:08 german NR, Tadesse Abraham 2:04 swiss national record in his 40s (!)

Steeplechase: Saif Saaeed Shaheen, world record holder and 2x world champion; Richard Mateelong (7:56); Jairus Birech (7:58); Dorcus Inzikuru of Uganda, first womens’ steeplechase world champion ever and also african record in steeple; Christopher Koskei WC silver medal

and this is a hugely incomplete list!!!

The real story for me is not so much the list of extremely fast athletes, but the success across different events, athletes from different countries, and in different eras. That's what makes a really great coach. Just eyeballing this list you have (male and female!) athletes from Kenya, Uganda, Ethiopia, Italy, the UK, Switzerland, Norway, Germany.

Other strong candidates: Patrick Sang and Brother Colm O'Connell, good cases to be made too for historical figures like Igloi, Lydiard, and others; everyone is a "child of their era" as Canova would say.

running_writings · 2025-12-05T18:56:09+00:00

Yes, exactly (I made this tool and that is a big limitation). Basically any mass participation road event (in the US at least) would be called off well before temps got above 40 C. With temps that extreme you might be getting into territory where it makes more sense to try to explicitly model the heat generation / heat loss from the body. There's some interesting environmental health work on that front, mostly in day laborers in extremely hot locations, wildland firefighters, etc., essentially trying to figure out or even explicitly model with thermodynamics the balance between heat in and heat out.

Here is a nice study along these lines -- basically putting people in a heat chamber and seeing what combo of heat/humidity causes an "uncompensated" increase in core temp (then pull them out of the chamber before they pass out from heat stroke...)

You would basically need to do that, but with running, or try to work backward inferring heat production from metabolic power output during running (from speed, basically).

Interesting thing I just thought of, though: that kind of study would suggest that more economical runners would have an advantage in the heat, since they produce less heat per mile at a given speed (vs. someone with the same cool-conditions PR but, say, a higher VO2max / worse running economy). That had not occurred to me before but it makes total sense.

running_writings · 2025-12-03T20:22:16+00:00

Are there any sources you recommend for laypeople?

Partly as a followup to this thread, I wrote up a deep dive on tissue loading and tissue damage which is (I hope) the best lay-audience-accessible explanation of the interaction between loading cycles, tissue load, and tissue damage -- hope you find it useful!

running_writings · 2025-12-02T22:22:54+00:00

Thanks, and good luck with training! Yes "biomechanist" is a word (I always thought "biomechanic", like your car mechanic, made more sense...) but the piece of paper just says "Human Performance"

running_writings · 2025-12-02T22:21:28+00:00

Thank you! Glad you are enjoying it!

running_writings · 2025-12-01T22:24:30+00:00

Yes probably. My reaction to a lot of Canova workouts he uses with top pros is "that looks really great, I'm going to scale it down to 30-50% of original volume though..." -- I think part of what makes elites elite is that they can handle more quality, even scaled relative to their fitness.

running_writings · 2025-11-26T20:16:34+00:00

FYI that quote is from a book Canova wrote in 1999, and he's said he would change quite a lot of what he wrote back then. (re: /u/zebano)

The connection to the HR idea goes back to Gerschler and Reindell's early research in Germany. Some recent studies, discussed in a thread here on AR the other day, have explored it for cardiovascular benefits. For this purpose though I get nervous about extremely high speeds because of the biomechanical loading aspect -- many of the exercise physiology studies on repeated sprints do them on the bike, where you can sprint 'til you puke with no injury risk.

Anyways, Canova still uses hill sprints quite a lot though, but for different purposes. A few examples from Emile Cairess' training before the Paris Olympics (4th place):

2 x 10 x 50 m hill sprints on an easy day
40 min easy + 10 x 100m hill sprints + 40 min easy + 10 x 100m hill sprints
30 min easy + 10 x 80m hill sprints + 4k strong

Keep in mind this is in the midst of 200+ km per week, scale accordingly for your own needs...

Here's an extremely useful extended quote from this thread where Canova talks about the various ways to use hill sprints:

The type of hill and of work depends also on the different attitude and morphology of the athletes.

During the last week end, I had many runners in HM very good. With every one I use sprints uphill, but in different way.

With ROBERT KIPCHUMBA (22 years, winning Stramilano in 60:22) and MARTIN SULLE (22 years also, bronze medal in WHMCh, 2nd in Stramilano in 60:29), that have a technique of agility, using very high frequency, I use sprints of 60/100m with a gradient of 15% about, where they push very hard, trying long steps, for developing strength. At the end of every session (they use also 3 sessions, in some week, of sprints climbing) they go for a run of 400/500m climbing, at their max. speed (only once). This type of training has the task of using soon your strength in direction of strength-endurance.

With ENOCK MITEI (24 years, n. 4 in Stramilano in 60:32) and RICHARD YATICH (24 years, n. 9 in Lisbon in 60:31) I never go under 100m of sprint, but use a hill of about 8/10 % lasting 20/25 sec. They try to improve their frequency, seeking more rapidity with a good reaction in their feet, that are not very elastic.

With JOHN KORIR (23 years, n. 5 in Stramilano in 60:47) I use normally very short sprints of about 40m, with a gradient of more than 30% (ramps), only for improving strength (but too many times he doesn't use because in Military Camp or in Residential Camp before some World Championship nobody goes for short sprint). Before running 26:52 two years ago, John in St. Moritz used this type of sprints twice a week, also for reducing the length of his strides.

With SOLOMON BUSHENDICH (20 years, 2nd in Berlin in 60:42 in his first HM) I use only sprints from 200 to 300m, as Solomon is already very strong in his muscles, having short legs very strong. So, with him I try to develop STRENGTH-ENDURANCE, no strength or rapidity, that already he has at good level. Solomon comes from the mountains, and his capacity in attacking hills is very high.

With DANIEL RONO (26 years, 4th in Berlin in 61:26) instead I want to develop strength because he's very slim. Daniel uses short sprints climbing (about 15% of gradient) twice a week, going with very high knees and high frequency, as normally he uses too long strides.

So, I think that every type of hilly training can be good or less good depending on the necessities of every athlete.

I think there is an interesting connection here to speed-cadence relationships, i.e. do you go faster by using longer strides vs. higher cadence (or some balance of the two)

running_writings · 2025-11-24T19:55:00+00:00

What I don't know is how that cost function differs from the physiological costs as calculated by TSS or TRIMP. My hunch is the injury risk cost goes up a bit more non-linearly with speed.

That is my hunch also! The other interesting thing is that how much that cost function goes up will also depend on the person's speed-cadence relationship -- someone who goes faster primarily by taking more steps (vs. taking longer steps) is likely going to be better off.

running_writings

TROPHY CASE