Finding LT HR

guv001

I'm currently reading Joe FRiels Training Bible and trying to establish my LT HR only problem is that in one area it tells me that I should take 5% off my average HR from the last 20mins of a TT and later it tells me to add it. Any experts know which it should be? Thanks for any help.

SteveR_100Milers

I thought that he says to ride a 30 minute TT at 10 pace, but take the average HR for the last 20 minutes, not the entire 30. This is your LT in Friel speak.

Ric_Stern/RST

guv001 wrote:

I'm currently reading Joe FRiels Training Bible and trying to establish my LT HR only problem is that in one area it tells me that I should take 5% off my average HR from the last 20mins of a TT and later it tells me to add it. Any experts know which it should be? Thanks for any help.

I've no idea what the "Bible" says, however, as a sports scientist and/or cycling coach, he's talking rubbish. Firstly, there's no such thing as lactate threshold HR. By definition lactate threshold is a measure of blood lactate and not HR. Secondly, lactate threshold has nothing to do with the HR sustained during a ~20-min TT, as LT can be sustained for up to about 3+ hours, and is equal in intensity to about 85 - 90% of the best effort that can be sustained for about an hour.

In exercise physiology, LT is defined as the work rate that elicits a 1 mmol/L increase in blood lactate over exercise baseline levels (which would be a lactate of 2.X mmol/L), or the work rate that elicits a fixed lactate of 2.5 mmol/L.

On the other hand if you wanted to set your HR training zones based on a TT (there are other ways of doing this that don't involve TTs) you'd probably be best basing them on a ~1-hr all-out effort. However, it's important to note that HR can vary significantly at this intensity due to a variety of factors (e.g., fatigue, cadence, altitude, temperature, etc).

Ric

Porkyboy

Ric_Stern/RST wrote:

guv001 wrote:

I'm currently reading Joe FRiels Training Bible and trying to establish my LT HR only problem is that in one area it tells me that I should take 5% off my average HR from the last 20mins of a TT and later it tells me to add it. Any experts know which it should be? Thanks for any help.

In exercise physiology, LT is defined as the work rate that elicits a 1 mmol/L increase in blood lactate over exercise baseline levels (which would be a lactate of 2.X mmol/L), or the work rate that elicits a fixed lactate of 2.5 mmol/L.
Ric

Hi Ric

Wonder if you could clarify the above for me please and let me know the source of the definition? What are you saying are "exercise baseline levels" Is the exercise baseline lactate level (you refer to 2.Xmmo/L) the level for an athlete who is exercising but not very hard? Is there a definition of this baseline in terms of % of FTP or something like that which can be nailed down?

Can you give me the 1,2,3 method you would use to determine LT. Let's say someone's resting (on couch) blood level is 1.4mmol/L.

I seem to remember that people at one time were saying that LT was somewhere in the region of 4.0mmol/L and a chap in CW last week was talking about his LT being at 4.6mmol/L. All very confusing, for me anyway!

Any help would be appreciated.

PBUK