Anyone ever do a (blood) Lactate test?

[Ghost234]

I'm curious if anyone has ever done one. How accurate was the result? How did it affect your training plan? What was your result like in comparison to your 20 minute power?

[markc]

I took advantage of proximity to a good University human performance laboratory in the post-season to do one. Was curious what the values would look like. My LT was very close to what was expected based on training seriously with a PM for the last 5 years.

We used a stepped test also known as the L 4mM type test. Next time I am near the lab I'll have a go with the MLSS protocol.

Did any of this change my training? No. LT was very close to what the coach and I had estimated so there wasn't action to take. Fun to have the numbers though. If you like that kind of geek stuff.

[cookiemonster]

Yes, I did one at the beginning of this year. I'd previously done a couple of VO2 / ventilation threshold tests - so just with the mask measuring the CO2 and O2 you're breathing out to estimate threshold, but this was the first time I'd done the pin prick test.

As you no doubt know (and depending who you listen to) there are two lacatate "thresholds". The ventilation threshold tests estimate the upper threshold (max lactate steady state, OBLA, anearobic threshold, whatever you want to call it!) which corresponds well to your FTP. The blood lactate pin prick test also measures the lower threshold which is the initial rise in lactate from its resting baseline. This corresponds to the transition between training levels 2 and 3 (base to endurance).

Most of the talk on training these days seems to concentrate on FTP and this higher lactate threshold as the be all and end all, but ignores the lower threshold. The Coggan/Hunter book for example has the power test at 5s, 1m, 5m and 1 hour/ftp - it doesnt go out further than that to, say, 3 or 5 hours. I think there are a number of reasons for this including the straight forward practical one thats its much easier to measure the higher threshold - you can get a good estimate with a 20 minute power test, but very difficult to get a good measure of your 5 hour power! Also its sounds better - my FTP was 325w (at 72kg) which sounds much cooler than my initial lactate threshold at 218w; FTP is more relevant to many competitive events such as 10 and 20 mile TT's and < 1hour crits; and finally, for many people today its possible to fit in 2x20's and the like but very difficult to schedule three or four 3-5 hour rides in a week.

From the lactate testing I found that although my FTP/second threshold was good (relatively! I was happy with 325w anyway), my initial threshold was poor at 218w - so I could perform up to an hour, 90 minutes, whatever, but it explained why I'd suffer on the longer stuff. As I was looking at doing some big long chunky events such as 100 mile road and stage races, the Raid Pyrenees and a couple of the big euro sportives, this initial threshold was my weakness.

The fact that you could raise your FTP, but with little effect on you base/endurance was a surprise (although in retrospect it shouldnt be as you can raise your neuromuscular power with little effect on vo2, your anaerobic with little effect on ftp, etc). I personally I found it useful to reorientate my training, and to break from the "cult of the FTP" The traditional long steady base/endurance pace rides still have a place; just because I dont measure them in a 5s/1m/5m/ftp power test doesnt mean that I can ignore them!

As an aside If you have a power meter, I dont see the point in measuring the upper lactate threshold at all; the 20 minute or 1 hour power test will give you the power you need for your ftp (knowing your lactate goes exponential from 4mmol/l at 317w doesnt give you anything you can actually use at home)

Jon

[Ghost234]

Thanks for the info. I was asking because I recently took advantage of one of these tests and the results were much lower than I was expecting. At 4mmol they were saying my threshold power was nearly 25% less than what my most recent 20 minute TT power was (this was done about 2 1/2 weeks prior to test). I found it very strange. But having never really done an "hour all-out" it is pretty difficult to base the result off anything concrete.


My blood lactate went above 4 pretty early, but it stayed pretty steady, slowly increasing, until my "guesstimated" threshold power. After that point it went up exponentially.

[HillRPete]

Thanks for the info. I was asking because I recently took advantage of one of these tests and the results were much lower than I was expecting. At 4mmol they were saying my threshold power was nearly 25% less than what my most recent 20 minute TT power was (this was done about 2 1/2 weeks prior to test). I found it very strange. But having never really done an "hour all-out" it is pretty difficult to base the result off anything concrete.

My blood lactate went above 4 pretty early, but it stayed pretty steady, slowly increasing, until my "guesstimated" threshold power. After that point it went up exponentially.

That usually means you're training hard too much, and not enough in the lower aerobic zone. (If discussion of your results was included, the probably told you something like that).

[Ghost234]

Are you refering to Z1/Z2? or the range in which I reached 4mmol?

[HillRPete]

It's really hard to comment in detail without seeing the actual graph, and even then I'm just a backseat commenter merely tying to make the best of my own training, rather than a proper coach or even sports med