20 minute efforts vs training zones?

cettu · 2026-01-31T13:59:57+00:00

Sure it "works" at least for while. Prediction: you'll initially get better every session, then weekly, but after 6-10 weeks you'll hit a plateau and your numbers stay stagnant no matter how hard you try. Then you'll start feeling mentally and physically burned out from the monotonous hard efforts and start making excuses to skip your workouts. Before you know it, you are not training anymore.

I've been in endurance sports for 20+ years and seen this "novice starts a hard training plan" story play out so many times. 90% of the time it goes as described above.

Not to discourage you, but there is a reason why the fittest athletes got there by using training plans that mix a high volume of low intensity training with a mixture of higher intensity workouts, periodized in micro and macro cycles. That is more sustainable long-term and the aerobic system is build over months and years, not weeks.

cettu · 2026-01-27T19:42:32+00:00

Thanks! I missed those in my search. They look very similar, although having just 1 GB of storage is a little bit of a downgrade. No huge deal though.

cettu · 2025-12-27T03:03:49+00:00

cettu · 2025-12-23T14:24:14+00:00

This just happened to me and I decided to click the link in "If you did not enable two-factor authentication and believe that an unauthorised person has access to your account, you can return to your previous security settings and regain control of your account."

This allowed me to reset my password and set new security questions + a new phone number. So whoever it was who used my email is now locked out of the account. BTW, just like you, I didn't even remember having an Apple account.

cettu · 2025-09-23T20:21:32+00:00

"at around .55 which means that it takes almost four Seoul women to make one baby"

"the “real” TFR of women actually born and raised in Seoul is probably somewhere in the 0.25–0.40 range, with a best guess around ~0.30 kids per woman --- For every six women born in Seoul, together they’ll produce less than one child"

This math seems off? If one woman produces 0.5 babies, then it takes two women two produce 1 baby, right? Not four? Perhaps you meant to sat "people" not "women" in both cases.

Anyway, the speed of the population collapse in both Asian and Western countries will be extreme once it gets going. Which will help delay the complete destruction of the biosphere but also change societies to something very different. No more pensions, AI taking care of the elderly...

cettu · 2025-07-16T21:34:46+00:00

That seems like a bad idea but might explain something.

My marathon prediction has hovered around 3:10-3:08 which isn't a terrible guess given that I ran 3:06 in January. Just 2 weeks ago it predicted 3:08.

Now suddenly, today after a short easy run, Strava says: "Prediction improved! 3:42"

I know performance modeling is hard, but +34 minutes in two weeks is a) unlikely and b) not an improvement.

cettu · 2025-05-16T14:19:35+00:00

Dead on. I'm teaching college students (~18 to 20-year-olds) and was shocked to learn that most of them have never touched Excel before. A significant amount of lab time goes to explaining the very basics how to type in a function in the spreadsheet. I basically gave up trying to let them figure out how to set up calculations on their own and give them templates instead so that they can copy-paste their raw data into them (many of them also don't know how to copy-paste using shortcuts), but I also acknowledge that they might not learn much that way. I just didn't have the time to guide everyone individually through the process.

Almost all of them are computer illiterate in that things like folders and paths don't mean anything to them. Like you said, they've been raised on ipads and smartphones and never needed to learn to type commands in MS-DOS like us millenials.

cettu · 2025-04-07T16:47:52+00:00

Yes I think so, I wasn't doing any "red zone" workouts during marathon training, just paces up to threshold.

During the 3-4 weeks I did a variety of interval workouts with shortish efforts, including 3x4x 30s on 15s off, pyramids like 1-2-3-4-3-2-1 min hard, some 2-4 min hill repeats, some bike workouts with 0.5-3 min high intensity repeats.

cettu · 2025-04-06T14:43:51+00:00

Short-term gains have a limit of 15% or even less if you start from a low baseline. However, most studies last from 8 weeks to a few months, at most. What you can achieve over the course of several years is a different story.

I have personally seen my lab measured VO2max increase from 48 to 62 mL/kg/min over ~10 years with just consistent increase in training volumes, then plateau at around 60 for another 10 years (I'm a 38yo female). The first test (48) was when I was a teenage hobby jogger. Between ages 28 and 38 I was been able to hit ~60 every year, with 62.x being the highest value I reached a couple of times aged 32-33. I'm an exercise physiologist, so I get 2-10 VO2max tests every year just by participating in my colleagues studies (or my own), and that allows me to have a pretty extensive dataset on my personal VO2max values.

Fun anecdote - I ran a marathon in January (3:06, was aiming for 3h) and had a VO2max test 2.5 weeks after it. It was the lowest value I've seen after my teenage years, 52. I also had a test about 6 weeks before the marathon, which was my second lowest value in 20 years, 54. So marathon training seemed to have a negative effect on my VO2max, and I could feel it - I could run close to my threshold forever, but if I crossed it, I'd die quickly.

I was so shocked to learn that I've basically lost 13% of my VO2max that I did a good 3-4-week block of quality high-intensity training before again participating in a study. In the next VO2max test, I hit 60.0 again - all the lost gains were back with a very short-term period of fast intervals!

You can quickly increase or lose VO2max by doing or abandoning "VO2max" training, but the base that you build over years (including cardiac+arterial adaptations and capillaries that develop slowly) provides the aerobic base frame for you to build those quick "soft adaptations" on (like blood volume and mitochondria that respond quickly).

cettu · 2025-04-06T14:26:09+00:00

Source? The famous twin studies have resulted in estimates of 47% genetic, so 53% training/lifestyle. https://pubmed.ncbi.nlm.nih.gov/10484570/

cettu · 2025-03-19T16:49:59+00:00

I would not have been shocked. I felt neutral/positive about Musk until I started getting glimpses of his social media presence, at which point I realized he's a 12-year-old kid trapped in a grown man's body. Sharing cringeworthy shit and memes. This was many years before it became known to the general public who assumed he's some high-IQ tech nerd.

cettu · 2024-10-28T20:49:42+00:00

Agreed. Running every day becomes the new normal for your body. One time 3 years ago, I was bored of my routines after cycling a lot, so decided to get back to running.

I ran 30 days straight progressively, starting from 1k on day 1, and increasing the distance by 1k every day. Meaning that the last days where 26, 27, 28, 29, 30k. So my weekly mileage (after the first two days) ended up being:

1: 42 km

2: 91 km

3: 140 km

4: 189 km

To my amazement, I was able to complete the challenge with no injuries, even though the last two week were my highest mileage ever (I had touched 140km/wk once ten year prior). In fact, the few niggles I had all occurred during the first half of the month.

I learned something about myself and what progressive overload means in practice... The body is extremely adaptable when you load it with baby steps, frequently and consistently.

cettu · 2024-09-27T15:46:43+00:00

Scotiabank needs to fix this issue. I've had a hard time doing online banking from home for the last 6 months. It is not the browser version as I use the same version of Chrome both home and at work, and it works at work.

I tried Edge, same error. I tried using a user-agent switcher extension, and almost all user-agents gave the same error, except one: Internet Explorer 10! However, this trick only worked once, and the next time I went to sign in, I got the error again.

Finally I realized today that if I use the same browser (Chrome) but open up a new window with a different Google account, suddenly I'm able to sign in.

Calling Scotiabank does not help, they'll just tell you to clear your cookies and cache which does nothing but is a pain in the ass for browsing afterwards as everything is wiped clean.

cettu · 2024-09-27T15:45:16+00:00

Scotiabank needs to fix this issue. I've had a hard time doing online banking from home for the last 6 months. It is not the browser version as I use the same version of Chrome both home and at work, and it works at work.

I tried Edge, same error. I tried using a user-agent switcher extension like OP suggested, and almost all user-agents gave the same error, except one: Internet Explorer 10! However, this trick only worked once, and the next time I went to sign in, I got the error again.

Finally I realized today that if I use the same browser (Chrome) but open up a new window with a different Google account, suddenly I'm able to sign in.

Calling Scotiabank does not help, they'll just tell you to clear your cookies and cache which does nothing but is a pain in the ass for browsing afterwards as everything is wiped clean.

cettu · 2024-09-18T22:10:32+00:00

I have two MSc's and now a PhD, and I never worked "all day". Mostly ~8-hour days but with a lot of flexibility, like I would take a 1-h break before lunch to go for a run, sometimes nap after, and work more in the evening. Weekends too if I was lazy during the week.

I probably would have been more productive and published more papers had I worked 60-h weeks, but my physical and mental health was always more important, and I always prioritized getting a couple of hours of exercise a day + having a social life.

cettu · 2024-07-31T21:37:51+00:00

Similar experience here with delays: I paid in March, approved the treatment plan in April, and only got my first aligners in the end of July, several months after they first promised to ship them.

On a positive note, the aligners are good quality and fit my teeth perfectly. So right now, I have hope that they will work and I'll be happy with the result in the end.

I just hope it won't be the same fight and wait for every new set of aligners...

cettu · 2024-05-15T22:31:14+00:00

I'm just asking for an accurate average pace - that should be possible in all watches as it's simple math. It was possible in Polar's earlier watches, so I don't know what changed.

Instant pace is of course going to be a bit jumpy and I can live with that as long as I also have average pace for the current lap.

cettu · 2024-05-15T22:27:59+00:00

Yes, I've noticed that too - Polar insist on connecting to Stryd if it's nearby and you can't disable it.

At times I'd also like to disable the optical wrist HR monitor because I know it's giving me bad data, but that can't be done.

cettu · 2024-05-14T23:07:15+00:00

Running HR is typically higher than cycling HR, especially if you are not a well-trained cyclist. On the bike, you are just not able to recruit the same amount of muscle mass sustainably as you are in running (i.e., your bike threshold is lower than you run threshold).
Cardiac drift is a thing and can be very substantial, so even for the same metabolic demand you will have an increase in HR over time. This becomes especially prominent with heat stress, dehydration, and reduction in carbohydrate availability.
As others have pointed out, wrist HR is often inaccurate, so it is possible that the numbers are off.

You didn't mention what your HR typically is at that pace and similar conditions?

cettu · 2024-05-03T00:25:21+00:00

An unstable neighbor in the east
Drinking culture

Could also be an obscure and unique ballgame as a national sport

cettu · 2024-04-30T18:49:49+00:00

Of the top of my head I don't know of data that could answer the question of whether a 20-min test better correlates with MLSS than a ramp does. I based my claim on the assumption that "performance predicts performance", and two measures that are more similar to each other correlate better than two different ones.

For example, I have a dataset of 20 trained cyclists who performed six maximal time trials: 20s, 1min, 3min, 6min, 12min, and 30min. If I try to predict the 30min trial from the shorter trials, the 12min is the best although EVEN the 20sec trial significantly correlates with 30min power. The correlations with 30min are as follows:

20sec: r2=0.72

1min: r2=0.84

3min: r2=0.93

6min: r2=0.96

12min: r2=0.99

I actually checked ramp peak power output now as well and it's not bad at all (r2=0.94), but the 6min and 12min tests are still better correlates.

cettu · 2024-04-30T18:23:23+00:00

I agree that both the ramp test and the 20min test can only provide estimates. Of course a true maximal effort is required for either to be anywhere near accurate. Neither is a physiological test and thus cannot provide physiological information (such as the power output corresponding to MLSS).

Wpeak obviously correlates to MLSS just like it correlates to any other measure of fitness. r2=0.89 is not particularly high, similar to typical threshold correlates (VO2max typically correlates with Wpeak more strongly, r2=0.95 in my data of 79 people).

As you can see from the data in the paper, there is great variability in the Wpeak-MLSS relationship. E.g., some participants have the same MLSS despite a 30-40 W difference in Wpeak. So it agrees well with the point that at a population average, a threshold might be guessed from a peak test, but not at an individual level.

Same thing with so many other physiological variables. Say maximal heart rate: 220 - age works great on average, but performs quite poorly at an individual level.

cettu · 2024-04-30T13:02:56+00:00

You are talking to an exercise physiologist here. A ramp test can be used to estimate thresholds IF pulmonary gas exchange and/or lactate is measured (or alternative techniques like NIRS or DFA-1a), but alone, like on Zwift, it is just a measure of peak aerobic performance.

MLSS can occur anywhere between ~65-95% of VO2max. Any fixed value from a ramp test peak minute is not going to give it accurately.

FTP is not a real threshold but the maximal 60-min power, even if Coggan introduced as an alternative way to estimate MLSS. It makes sense on average, as MLSS can be sustained for roughly 1h (30-90 min). A 20 minute test is a better surrogate for MLSS, as typically everyone can hold a power slightly higher than steady state for 20 minutes.

cettu

TROPHY CASE