Universal intensity description for runners (%CV)

I agree that running is a skill. That is another reason why I think my example of a workout with 4k of volume at 10k pace is still a non-negligible stimulus. You are getting practice running at 10k pace, without your form breaking down.

That's what I thought you meant. There is so much misinformation about metabolism. The PED concept for example. It doesn't make sense metabolically. But everyone believes it because they don't really understand what metabolism is.

And the skill factor is largely ignored in the ex phys literature because those who do research metabolism greatly overstate the importance of their work.

If i got you right you have a 1/2 marry time and estimated your short distance times. If my understanding is correct, it does not work that way. Optimally you have to do 3-4 time trials between 3-23minutes to estimate CV. It can also be estimated from a 5k race (<23min) which is not so accurate but ok.

So taking your 01:34h 1/2 M time i would estimate a 5k of 20:30. This is a CV of 14kph (04:18/km). But please be aware that this is a rough estimation. If you train in hot conditions you should adjust down (slower) a bit.

It is oulined from the beginning of this thread with papers, videos and explanations from my side following my first post.

You repeat and repeat now over and over again the same thing and do not contribute to the topic. Therefore, i will ignore similar stuff from your side in future. We are not in the kindergarden here.

So what is 'critcal' about 10k pace? It's just a pace like any other. There is nothing special about it as a training pace.

The terms Critical Value or Critical Velocity are pretentious.

Got it, you have no other definition other than your words I quoted and are just randomly blathering here like you have an actual point.

CS is a measure of the speed you can hold for at least 30 minutes. The 30 minute time frame was already established for measurements of stable blood lactate (MLSS evaluation). The 30 minute window is arbitrary - enough time to get up to speed and stabilize, holding it there for sufficient time to see if it is "steady". So, as far as I can see in the cited papers, it all comes down to a time delay between a runner's muscles being able to get enough oxygen and process the lactate and other metabolic products (the factors that determine being just below CS), and the time when the excess enters the blood (hopefully not exceeding MLSS). CS is a tad bit faster than MLSS. So, you can safely plan "severe intensity" workouts at CS in less than 30 minutes and not exceed a threshold that will make your muscles crash and burn. That "severe" intensity right below CS is a stable doable effort. But if you try to continue, the blood will start to feel it and you might exceed your MLSS after only 20 minutes, and have to slow down or stop. Instead, you might throttle down to your slower MLSS "heavy" intensity so you CAN hold steady for at least 30 minutes.

Seems to me that hair splitting between MLSS and CS is something that would only be useful for some tightly controlled lab study.

In the paper i provided the authors suggest, 'we found that modifying the criteria to a 2 mM increment in blood [lactate] between 10 and 20 min increased the group mean running speed at MLSS and eliminated the difference between MLSS and CS.'

So yes, it seems to be a matter of definiton of MLSS. The drawback of MLSS is that you need a) a lactate meter and b) a lot of trials to find it.

CV is, on the other side, a very good performance indicator and can be evaluated without a lactate meter. This is a plus i would say.

Read what you wrote well... what speed did you use in your example?

P.S.

16-mile marathon pace is a great workout for even a pro.
For the Italian school, for years and years, from Bordin to Baldini the continuous marathon rhythm is standardized between 18 and 25 km...
Canova is now trying higher km, but at speeds a little lower than the marathon pace, but at the cost of then having to do then 10-12 days of total unloading, and the results are not very positive...Sondre Moen never recovered this workout and failed the next marathon.

Standardization is 18-25 km.
It does not fit with my example of 25 x 400 meters.
Standardization:18-25 km at marathon pace = 25 x 400 mt at 3000 mt pace.

Where from to you have that theory? Source?

Your theory is not in line with my personal experience and even more important with science (energy systems). The body has 3 main energy systems, and their proportion to a movement is duration dependent.

Here is how you calculate Critical Power/Speed/Pace/Velocity/etc:

(Assumptions: Time is between 3 and 20 min, both tests are all out within a month of each other (at most), and all variables between tests are different (ie T1 is not equal to T2)

(Abs() just means absolute value, getting a negative doesn't matter, just keep everything positive)

Time Trial 1: Distance (D1) - Time (T1)

Time Trial 2: Distance (D2) - Time (T2)

Abs(D1 - D2) = D3

Abs(T1 - T2) = T3

T3 / D3 = Speed of CV

Example:

TT1: 1 mile - 4:20

TT2: 2 miles - 9:30

Abs(1 - 2) = 1

Abs(4:20 - 9:30) = 5:10

5:10 / 1 = 5:10 per mile is your Critical Velocity

This can also be done in meters, but can be harder to convert to mile pace

Example:

TT1: 1500m - 4:00

TT2: 5000m - 15:00

Abs(1500m - 5000m) = 3500m

Abs(4:00 - 15:00) = 11:00

3500m / 11:00 = 318.2 m/min (or 5.3 m/sec)

To get mile pace:

(x) / CV Speed (if m/min)

Or

(x * 60) / CV Speed (if m/min)

where x = desired distance in meters

(1609) / 318.2 = 303.4 sec/mi

which equals 5:03.4 mile pace

This method is very accurate, but ways to make it even more accurate are:

Keep time trials within one week of each other with equal training load going into them

Make sure effort is steady and all out (good pacing)

Conduct more time trials (I'm too lazy to write the math, but you can look more into it if you want to. The 2 time trial method is good enough, but with more trials, you can predict other race times in addition to CV).

Hope this helps and if anyone wants me to calculate their CV, feel free to ask (and please correct me if you see an error).

*One more note, Tinman's CV calculator is accurate if you either fit a normal endurance curve OR if you use a race between 15 and 45 min, otherwise your natural speed and endurance will affect the results and a two trial method can be much more accurate.

Also, Critical Power/Pace/Speed/Velocity/etc is a threshold. It can be found in other endurance disciplines and is being used in some team sports in different parts of the world (like soccer and rugby) by a few teams.

In decent swimmers, this threshold correlates to 3000m (similar to how it correlates to 10000m in decent runners), but for most endurance activities, it can be held for 20-40 minutes depending on your motivation, genetics, freshness, and ability.

It usually occurs between 80 and 90% of VO2 Max and is near the "thresholds" of MLSS and the second Ventilatory Threshold (VT2).

CV/etc is the fastest you can go while the use of oxygen increases, without ever achieving VO2 Max. Any faster and you will eventually achieve VO2 Max even though you may not be running AT vVO2 Max (this is similar to how if you run faster than vVO2 Max, you will never hit 100% oxygen usage (aka VO2 Max), because you will have to stop or slow down before that happens).

Sorry for the double post.

Lexel, and everyone else may be burying the lede here. Which is, WHY should we care about this? What does the CV model do that can't be done elsewhere, as easily or more easily?

So CV is "the fastest you can go while the use of oxygen increases, without ever achieving VO2 Max", neat but who cares?

You can use it to predict race times, okay we can already do that.

You can train at specific % of CV, seems reasonable, but why?

Maybe it gives us a common language to discuss training intensities, sounds nice, but requires the whole running community to buy in and start running a bunch of TTs, why would we want to do that? we like training and racing not TTing. You know what common language we already have: standard race distances. done.

What does the CV model do that can't be done elsewhere, as easily or more easily?

I understand what you're saying and you make sense, I just have one disagreement with you. The numbers I used were made up, a 20 mile practice marathon pace run at 5 min/mi takes about the same amount of time for an amateur doing 16 miles at practice marathon pace when their pace is 6 min/mi (still a good runner, just not elite). Both are "hero" workouts and I agree that 18-25km (10-15 mi) makes more sense, but your earlier logic seemed to suggest the slower runner should do more volume by distance, because the race requires it, even though they would end up spending more time working out than the profession/elite runner.

The only reason to care about this is if training theory interests you, and I'd hope athletes and coaches that want to get better do have that interest. If you don't, then why are you reading this?

To give a real world example:

Say an athlete just raced a 1500m and a 5000m and set reasonably large PRs and needs to adjust training paces, but the coach is unsure how much their endurance paces need to change.

One option is to perform a lab test and lactate meters, but that requires an additional workout day that could be used to focus on getting better, rather than analyzing.

Another option is to estimate the change in paces, but unless you've been doing this a long time, this is tough to do with confidence.

A third option is no change, don't fix it if it ain't broke, but I believe this options lowers the ultimate potential of the athlete that season and seasons to follow.

Another option is to calculate their CV from those two races and get an almost exact value for their training pace and use %CV for other endurance training paces. This is practical and almost as good as a lab test, especially if you keep athlete specific information season to season. Maybe the CV pace didn't move at all? Then the VO2 Max or Sprint speed is probably better and that can tell you to focus more on the endurance side. Maybe the CV became way faster? Then it's time to work the VO2 reps and sprinting!

The beauty is it gives you an athlete profile that adapts to the athlete and allows for better training judgements and more confidence in your decisions.

No one is saying this is a game changer or that you have to use it, but it is a very useful tool that anyone can use and may give you that 1% edge on others.

I wouldn’t call it an error in the math but more so one in concept. Per your method, you’re taking an average rate of change in time with respect to distance of a non-linear process. Using shorter distances and/or intervals, in the 2-20 minute time frame that is generally proposed in the literature, will yield a faster Critical Speed (CS) than if you use longer ones. The first paper lexel attached lays out the concepts and model very well. As well as how to derive the CS and the definition of it.

I do agree with others that CS seems largely of interest (and possibly application) to researchers. Both in terms of precisely defining it and calculating the speed. However, from the research it does seem to demarcate an intensity where below CS, you can achieve a steady state (of course not infinitely though) with regards to BLa, VO2, pH, and PCr values. This is per Andrew Jones, Anni Vanhatalo, and other prominent physiologists.

For those who haven’t read the paper (and who can blame you), the two parameter model is laid out very plainly:

Time = D’ / (Speed - Critical_Speed)

Where Time is measured in seconds, Speed in meters per second, and D’ is the curvature constant (the distance one can cover when above the CS).

Note that they linearize the equation as follows to obtain parameter estimates:

Distance = D’ + Time*Critical_Speed

It’s suggested you perform 3-5 trials that last approximately 2-20 minutes in duration, so 800m to 5km for most of us, I assume. From there you can estimate your CS. Performing a linear regression with any statistical software gives you the parameter estimates for D’ and CS. You can also have fun using calculus or linear algebra and minimize the SSE if you feel so inclined LOL

Like others, I question the functional purpose. We already have relatively accurate race prediction calculators, which the formulas they derive their values from can also be used to calculate an accurate pace for a race DURATION too, not just a race distance. So if you wanted to use 30 minute race pace, 60 minute race pace, etc. You can do that and only have to run one race (or time trial), as opposed to the 3-5 suggested by the researchers, to get those values. To me, it’s not really improving on what we already do in our training.

So 10k pace is slower than 5k pace?

Really who would have guessed?

Maybe instead of metabolism I should have said "biochemical pathways." You need "practice" stressing those biochemical pathways, just like you need practice running correctly.