How to destroy aerobic capacity

March 17, 2018  ●  3-minute read

I’ve had a high anaerobic threshold for the past several years. Six weeks ago, I followed some bad advice and did way too much intensity for my fiber type. I almost blew up. I had one race during that period, and I finished several minutes behind my usual cohort. (Several minutes is a lot.)

Now I’m struggling to finish the race season and looking at a lot of repair work to get back to where I was. My aerobic threshold heart rate is usually between 180-185 bpm. Today, it’s down to ~170.

“There’s not a lot you can do to make an athlete better in the last month before a race. But there’s a lot you can do to make them worse.”
~ Renato Canova (paraphrased)

A difference of ten to fifteen beats per minute may not sound like much. But my skimo race pace is in the high-180s. Racing for two hours at ~188 is a very different experience with an AeT of ~170 than with an AeT of ~183. Races feel a lot harder and, afterward, recovery takes a lot longer.

Stupid is as stupid does

I have two principal interests: training and investing. I hired a coach so that I could be more effective and end the frustration of a split focus.

The coach was from a different school of thought, but based on his resume, I was sure the differences would be small. He’s had significant success with many athletes at a very high level. I assumed there would be some common ground, and that I’d learn a lot. Despite some early warning signs, I emptied my cup.

I felt fantastic for two weeks. It was a lot more intensity, but it seemed to be working.

But then I started to slow down. I could no longer match the paces that I had hit in the first few workouts. I told my coach that the workouts were feeling harder. I was having trouble completing them, and my pace was slowing.

I received no response. Nothing changed in my workout prescriptions. He cut-and-pasted workouts from one week to the next.

Generic programming was not what I signed up for.

“If you are not getting daily feedback, then you are not getting coaching. You’re getting a training plan applied to you.”

I disregarded the warning signs, insecure about my knowledge in the shadow of his. I knew better than to do so much intensity, but I didn’t have the confidence to say so.

Now I know better.

Stay the course

To make matters worse, the start of this season was perfect. Last summer, I tried several new training ideas that I responded to really well. I went into the winter feeling quite strong.

In early December, a spot lactate test was one of the best I had ever had. Rather than ~2 mM in the low 180s, I was at only 1.8. The day after that spot test, I had a new race experience, feeling stronger and stronger as the race went on. Except for some tactical errors, the race was perfect.

Now I’m faced with one more race, low confidence, and the demoralizing prospect of rebuilding what I’ve lost.

The road ahead

The good news is that wasting over $1,000 may turn out to be the best training money I’ve ever spent.

I realized that I know more about training than I thought. I know what works, what doesn’t, and why that’s the case. I know what my weaknesses are, and I know how to fix them.

It’s just going to take another season to do so…

Image of intensity distribution for the entire season, before a good race, and before a bad race
Intensity Distribution: A) all season, including races (so intensity in training is overstated); B) before the good race; and C) before the bad race. Intensity above aerobic threshold (AeT) increased from 4.11% (for the good race) to 9.73% (for the bad race), more than doubling. Speed work (Zone 9) decreased from 0.45% to 0.00%.
NOTE: The zone system I use is unusual, but effective. It’s based on the work of Renato Canova and has two big advantages: 1) it uses aerobic threshold as the reference intensity, not maximum heart rate; and 2) it emphasizes much more polarization of intensity than more traditional systems. The lower six zones do not directly correspond to a generic zone breakdown, but zones 7, 8, and 9 do correspond to the traditional zones of 3, 4, and 5, respectively.
Posted in: endurance training