Lactate Threshold Heart Rate Test (Part I)

A key performance indicator for my training this year is my lactate threshold heart rate (LTHR). It is a barometer of how my body tolerates work. Knowing my LTHR enables me to identify my training zones as I prepare for this year's events. (More on all of this in forthcoming posts.)

Determining one's LTHR is easy—on paper.

You just do a 30-minute time trial in a controlled environment. Go all-out—steadily—for a half hour, and your average heart rate over the last 20 minutes is the magic number.

Trepidation and Preparation

How fit am I?

That's a daunting question for a 41-year old cancer survivor who remembers what it feels like to be unable to stand steadily or walk.

It's a happy question for a 41-year old who became obese in the wake of illness, and then dedicated himself to getting strong and losing the weight (45 pounds of it).

Either way, taking the test would be taxing. Never having done anything like it before, I expected it to challenge my mind as it tested my body. How long would I be able to concentrate? How far could I push myself? How would it feel?

To prepare I read others' accounts. In my spin classes I focused on steady-state pedaling for the entire 45 minutes—learning how it felt to stay within a zone, pedal through discomfort, and listen to my body.

I also had to work out logistics. When? Where? With what equipment?

The Plan

When?

• Sunday morning (while BCB and the LAs went to church).

Where?

• The living room!

With what equipment?

• Bianchi with winter wheels
• Borrowed stationary trainer (there is no way I could do it on rollers...and special thanks to Christopher the Generous for the lend!)
• IPod
• "Spinervals 27.0: Threshold Test and Suffer Fest"

It's all self-explanatory, except for that last part: the DVD.

I had asked Santa Claus for one of these magnificent downloadable sufferfest videos.

I did not get it. Boo hoo.

Santa, however, knows things. Sometimes, he simply gets things right. Clearly, I was a good little boys

So, my stocking had Coach Troy Jacobson's video. Brilliant!

The DVD is a 60-minute workout designed around the functional threshold test. It has basic warm-up, targeted heart rate ramping, the test, and cool-down.

It works.

Just don't listen to the music (it's a cross between 80's porn music—not that I would know—and the scintillating sounds of the John Tesh Orchestra).

The Test

I finally had the necessary components for murdering myself. I had motive (after all, it had been weeks since I first intended to do it), I had opportunity (family out of the house), and I had weapons (borrowed stationary trainer, television, DVD, iPod).

I warmed up using the DVD's guidance. First it was your basic spinning—getting comfortable, waking muscles, focusing mind. Heart rate in 130s. Then a few intervals with increased resistance and effort stepped-up the heart rate. I got into the 160s with concentrated effort and intention to do so.

At this point in the proceedings I was comfortable in the saddle and hydrating appropriately, but I was bewildered by my HR. As soon as I reduced intensity it would plummet to the 120s. On the one hand, I was happy to see that I could recover efficiently. On the other hand, I had no idea how I was going to "get it up" for the entire duration.

Warm-ups finished; it was time for the test. I turned on the iPod and let AC/DCs primal, mid-tempo growl penetrate my core. I was about to perform on a animal level—might as well channel animal music.

I dropped in to my 50x12 gears (compact cranks, wot) and hit it. I focused on maintaining a cadence of 102rpm.

Why 102? Because it is greater than 100, but not as loose as 110. Not to be snarky; it's simply comfortable for me.

At 10 minutes I was breathing heavily, but well in control, and my legs had a steady burn—nothing severe, but I knew I was working. My heart rate was in the 170s, and it appeared to be pegged at 176.

At 15 minutes, no changes. I was sweating more, getting that pinkie-and-elbow drip. Everything was steady.

I was enjoying it. the video gave me something to focus on, and Coach Troy's motivation (or, what little of it penetrated the the Young brothers' growl) reminded me to focus. I only caught myself in a mind-wander once, and my cadence dropped to 95. I quickly compensated and got back on track.

As 20 minutes approached, I got a lot out of the video. Watching others push through to the end—especially Luther, the Clydesdale triathlete who was pushing for 600 watts in the final minute—fired my competitive spirits.

I finished the test and spun down. The video has a few post-test intervals, which were well worth doing. They re-invigorated my legs after the steady-state push.

My results?

See Part II...