Q's about cardiac drift WRT LT

Triathlon Forum
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couple questions here about cardiac drift (lol…came up with them during a long run this morning)

  1. how long does it take for cardiac drift to have any significant impact (on pace?)

  2. how does cardiac drift affect lactate threshold…i know there was a post in another thread that lactate threshold is a pace rather than a heartrate…i was wonder if as your HR increases, you will reach LT at the same pace that was previously sub-LT.

  3. is there a way to avoid cardiac drift (besides slowing down?)

thanks,

-kevin

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bump…

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I’ve noticed over the years that the time when drift occurs differs with my fitness level. No shock there.

In the early season HR drift occurs realatively soon. Opposite during in-season/peak. So with fitness comes the ability of the body to perform more effeciently, and for a longer time (which would seem rather obvious).

As far as HR drift on LT pace, I would infer from above that you would be in LT pace earlier and for a longer time the less fitness you have. You may blow straight through LT and redline sometimes? As you gain fitness you would have to work harder to get in the zone and stay in it, which would lead to better performances.

I would always stick with the zones you have set in the beginning. If you had a stress test to determine HR max, that probably won’t change more than 1/2 beats during a season, if it changes at all. You’re resting HR may become lower the more you train. So those would determine new zones. I would continually check resting HR, but getting more tests done to try and determine if your max has gone up would be futile I suspect.

For resting HR, I take take it every morning and run a moving average to remove outliers from my data. (ie overtrained days, stress, hangover, whatever…)

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I’m not sure about this, but here’s my take.

Reaching your LT pace at a higher HR than you previously did probably means you’re tired/over trained/not hydrated enough.

For example:

I think LT or whatever you wanna call it is very affected by your condition (ie hydration, sleep, cramps, weather, etc). For example I did a vo2max test around a month ago, and from that it pinpointed my LT at 187 bpm (from the gas exchange). Overall the test was very bad for me (i was feeling very crappy), and I reached my LT between 186-188 bpm at 15 kph (4 minute/k pace).

Last week I did a pure LT with the pricking and again, my LT was 187. The difference was I reached it at 17 kph. This test was shorter (4x4 minutes at different speeds, instead of the 18 minute vo2max test with the speed increasing every minute continiuously). Also I reached a higher HR than when I did the vo2max test (205 vs 202, not that big of a difference but still). Does anyone know if your vo2max changes (even slightly) based on your overall condition from day to day? I’ve read somewhere there is something like up to a 3% difference, but I’m not sure.