Lactate testing

by by Andy, Answer by Marius

Lactate testing is usually not something you need to do in your training. But if you are training 7-10 sessions weekly and is ambitious in the sport it can be the way to go. I have done over 5000 of these myself.

Now, both the question and answer here can be quick technical though. I do not intend this to be the "normal" case on this site, just for this one time ;)

I received this question :

Hi Marius,

I did a treadmill lactate test and got these results:

2 mmol/ 15 km/h at 172, 4 mmol/ 17 km/h at 188.
My maximum heart rate is 205. So my anaerobic threshold is at 92 % of my maximum heart rate, and the aerobic threshold at 83% of maximum heart rate.

When I'm doing some tempo running I normally can just reach a heart rate of 175-180. Otherwise it feels just too hard. you once mentioned that it's not good to spend a lot of time at aerobic threshold except in specific marathon progression.

My numbers also aren't in line with your zone three training. In zone three i would always run around aerobic threshold.
My easy running is always under 70 % of max heart rate and I feel comfortable with it.

I hope you can give some helping information
Greetings from Andy

Hello and thanks for the question.

My answer to this is quite simple. Because the lactate test is usually done indoors on a treadmill and because of its nature (quite long in duration at a very progressive pace) you usually get some degree of cardic drift when doing the lactate testing.

What this means is that you get abnormally high heart rate when compared to lactate, a large factor being the sweating you are doing during the test.

The result is an "abnormally" high heart rate - and how much "off" this is compared to outdoors varies from one individual to another.

My own experienc with this is a lactate test a few years ago. It was done on a Monday, with heart rate at anaerobic threshold 181 and my max is only 192. On the next Thursday I did a lactate "field test" outdoors and my threshold at that time was only 172. At 181 on the other hand I reached 4.8 outdoors vs. the 3.0 as my turnpoint indoors.

Point is : use the lactate testing indoors first and field test outdoors 4-5 days thereafter. Use the indoors test as a "reference" for tests done under the same kind of environment later and do the same for the outdoor test.

All the best,
Marius