Lactate Testing - Data and Results

I don’t really know but does this make sense to you and fit in with your feelings?

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I thought I’d add another data point here. I’ve had these done at a lab (rather than home-test) because I’ve combined this with gas analysis too. I’ve left out the gas analysis, but the results have been very positive (relative to my goals) with a huge increase in fat burning. This has all been driven by a big volume (~12h per week) at zone 2.
I’ve been increasing my focus on long distance riding over the last 3 or 4 years, but this last 12-18 months particularly. In general, the speed of progress has been slow, but I’ve made a 20W or so improvement over 12 months.
Lactate 1

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Darn, first test in a year. LT1 down 10-15W. Was to be expected. Perhaps riding very often (last months) is not the same as riding (very) long not so often (before)

Though I must say I haven’t really done a lot of LT1 work for months. Last 6 months or so were extremely polarised. Not because I planned to but life made me train in such a way.

grafik

Will do more LT1 work again, just to see if I can move it to the right again. However, this would been to ditch the zone 5 sessions. Finally found my rythm with these Bossi intervals

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Thanks for the pdf.
“Once thought to be a waste product of anaerobic metabolism, lactate is now known to form continuously under aerobic conditions.”
Energy systems are interacting systems. Metabolism is amazing.

Guessing LT1 around 224?

@andrieshanekom What’s your max HR?

Have you done a proper warm-up? Cool down at t=60 shows the lowest conc.

I think I have a very wide range, around 51 at rest, immediately goes to 100 if I just swing a leg over the bike. FTHR 179, Max HR 195

No warmup prior to the 60 minutes detailed above. For what it’s worth, I always see lower HR after about an hour of endurance riding, goes up then steadies and often dips slightly at same watts. Always put it down to endurance engine takes time to warmup, but who knows.

As I was doing some endurance in the trainer the other day, I was thinking. What would happen to the baseline and LT1 estimation if you did 30m steps or 60m steps??

Wouldn’t some lactate accumulation start showing in the blood sample?

Isn’t the short test protocol vastly overestimating the LT1 “Threshold”?

Assuming it is more or less fixed at any given time (meaning the lactate concentration, not HR or breath rate, which don’t change as much).

Of course, it isn’t fixed. So:

  1. use same protocol to compare (like anything)
  2. don’t base training right at LT1 on anything other than faith (“at or around”? sure…that’s just tempo). But there is no such thing as “training at LT1”. False precision that carries over from ppl using power, in part. Also using HR, power, or whatever and saying LT1.

Unlike LT2, etc. (which don’t really exist), there is a point where lactate is at baseline levels, and then isn’t. It is not necessarily abrupt/inflection, not what I’m saying. But it goes up at some point. So I think LT1 is a thing, however it might be labeled.

The shift from baseline to “not baseline” (call it what you want) will be different after a longer amount of time than after (say) 20mins. Basing what I’m saying on seeing data from a previous coach of mine, which he shared with all his riders.

Maybe that’s your point? If so, yeah.

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Yeah, but seems like everybody in this thread is doing it wrong.

LOL. Touche.

There’s always the other thread, where they are trying to figure out how to breathe during a “VO2max session”. Intellectually the easiest thing I’ve ever done on a bike: determine when I’m breathing uncontrollably hard. You can’t not know it. :stuck_out_tongue_winking_eye:

Ok. I guess it’s better to start another thread called VT1 Testing.

That depends. Most people do a graded test. It’s a quick way to observe metabolic changes in one session. Of course, the shallower the ramp for the graded test, the less the overestimate should be.

You might find this interesting if you haven’t seen it already…

And here’s one example for step-duration vs. lactate reading. Quite a difference in 3m vs. 10m steps.

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My data testing myself and some friends suggests that LT1 testing protocols, for power levels below MLSS, a step time of 5-8 minutes is adequate. Around 4-5 min in a step, lactate will rise as high as it will go at that power level (step) and then stay there. Under five minutes is too short, so folks doing 2 or 3 minute steps are not getting good estimates as they haven’t achieved equilibrium at that power yet.

Yes, if you do too short a step time (2 or 3 minutes), you won’t be at steady state for that power level. But you don’t need 30-plus minutes to achieve steady state at each step. 5-8 min per step is a good test protocol. For power levels below MLSS obviously, because above MLSS there is no steady state to achieve and above MLSS lactate will continue to accumulate.

The graphs from GarageLab above are concordant with what I’ve seen in the basement lab here. Anything 5 min or greater is fine for step testing and LT1 determination. Small increases in wattage per step allow finer resolution of the estimate, but really aren’t necessary for estimating LT1 for our purposes.

FWIW, my longest MLSS test was for about an hour. Once the MLSS lactate level was reached at about 7.5 mMol, it sat there (+/- testing error) for the duration. In retrospect, would have been fun to keep going for 90 min, but I was getting tired :slight_smile:

A different question is if training at or around LT1 is a good or bad thing, and how often, and for how long. We can leave that up to a different thread. I’m comfortable saying we know how to determine LT1 and leave it at that for here as this is a thread about testing and interpreting test results as opposed to how to train.

Hope that is fun and all the best,

Darth

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My latest test. Was only looking for the first inflection point using 10 minute steps. Going to add reps at tempo during endurance rides to try and pound that curve flat out to/past 240. Going to have to eat so much food lol.

Date Watts Lactate HR
3/11/2023 140 0.7 115
3/11/2023 160 0.8 120
3/11/2023 180 0.8 127
3/11/2023 200 0.9 133
3/11/2023 220 1.4 140
3/11/2023 240 1.6 145
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Study on variability of data:

https://onlinelibrary.wiley.com/doi/abs/10.1111/sms.14347

I’m still trying to wrap my head around this one. What do you think of it?

Doesn’t trouble me.

The authors note in the discussion some of the things discussed in this thread. For example, lactate testing requires good protocols and control of things like protocol design, sample taking, warm-up and food intake ahead of the test. Their protocol also looks like it was designed for speed of testing not for robust lactate determinations so that adds variability too.

I agree with authors that single point or single protocol lactate testing is of little value. The value is over time if you incorporate the data with other metrics to get an overall picture of fitness. As always, its not necessary but can be useful in some settings.

$0.02 on a quick read.

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Also, the difference between 1.1 mol/L and 1.3 mol/L is ~18%. Not sure anyone would consider those two values substantively different. When lactate changes, it changes by a larger magnitude. And when the sample is contaminated, if you get a reading at all, it is wildly off so you know to discard.

The difference between 130bpm and 150bpm is ~15%, but those two heart rates are substantively different.

And, trends.

(of course check my arithmetic because I majored in a biological science in college :slight_smile: )

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