Skip to main content
Lactate Testing

Lactate Test #5: Progress

Scott Semple

On September 18th, I did my fifth lactate test for the season. As with previous tests, I did both the aerobic and anaerobic portions on the same day with a break and some food in between.

A graph of results from my September lactate test
In mid-September, I completed my fifth lactate capacity test of the season. The results are promising, showing improvements in both aerobic and anaerobic capacity. (The dark red line is the most recent test. The other grey lines fade as the date of the other tests get older.)

What does this lactate test show?

Anaerobic capacity has increased

In my last test, I used a pace of 3,000 mhr for the anaerobic test. I was just barely able to complete the 45″ interval. For this test however, I felt much stronger, although for not much longer. The first 30″ felt good; the last 15″, desperate. The result was an increase from 11 mM (in my last test) to 12.8 mM in this one.

I’m happy with that result. An increase in anaerobic capacity alongside an apparent increase in aerobic capacity is a sure sign that aerobic capacity has actually increased.

Anaerobic capacity pushes a lactate curve up and left. So if anaerobic capacity increases, but the curve still moves down and right, then aerobic capacity must have increased in greater proportion than the increase in anaerobic capacity. At first, it seems counter-intuitive, but aerobic and anaerobic capacities present relative to the strength of the other.

Aerobic capacity has increased

My heart rates are lower across the board at all intensities. That’s a good sign.

For lactate, values below aerobic threshold are all lower, but I still have a curious “bench” between 1,100 and 1,200 mhr. Hopefully I can lower those values in the next six to twelve weeks.

One thing to consider is the test protocol that I’ve been using. I’ve been using test stages of three minutes which may be too short. The other day, I talked to Jerry Cosgrove (from www.lactate.com). He said that test stages should be at least five minutes long to allow lactate levels to fully stabilize between readings. Stages shorter than that may produce higher-than-stable values.

For my next test, I’m going to do fewer samples points and longer stages. For less than 900 mhr I may still use 3′ stages since those are consistently much lower than aerobic threshold. As such, I think it’s likely they’re stable values.

What training led to this shift?

Here’s a breakdown of the training that I’ve done between my fourth and fifth lactate tests:

    Modes: max strength, fasted sessions, slightly faster easy volume, faster aerobic threshold work, only one local muscular endurance session, 30-30 sessions at 130%/65% of ~2mM pace, and my first anaerobic bounce workout.

  • Volume versus intensity:
    • 95.3% <= of AeT HR (versus 98.5% before my last test);
    • ~66% <= 80% of AeT HR (versus ~68%).
  • Specificity:
    • ~23% of training time was on (roller) skis (versus ~29%);
    • 100% was weight-bearing (versus ~98%).
Graphs of training distribution by heart rate
Training Distribution by Heart Rate Zone: The left-most graph is my training distribution for last season (2017/2018). The middle graph is the distribution for the current season (2018/2019). The right-most graph is the distribution between my previous test (on August 12th) up to the day before my most recent test (on September 18th).
Charts of training distribution by session mode
Training Distribution by Session Mode: The left-most graph is my training distribution for last season (2017/2018). The middle graph is the distribution for the current season (2018/2019). The right-most graph is the distribution between my previous test (on August 12th) up to the day before my most recent test (on September 18th).

How does this influence the next training phase?

Things are progressing well, so I’m going to keep on keeping on. I only have one more 30-30 session to complete the progression.

After 30-30s, I’m going to focus on anaerobic bounce workouts to lower lactate values at my anaerobic threshold. That progression is eight workouts, one every 7-10 days, so it’ll take me well past my next test.

On the endurance side, aerobic capacity workouts are increasing in speed from the low-90% of ~2mM paces to the high-90%. If things continue as they have, I should be well-positioned for my first race on December 8th.