jtupper/anyone...question about heartrate versus tempo/lt pace

Jtupper is the one with all the experience with this, and we can all learn from him, but I will give it my best shot. I honestly don't have the data to say whether or not it will change over the years, and if anybody does I am sure it will be Dr. Daniels.

My educated guess would be yes it will change to a small degree, for a number of reasons. I would imagine it would still be a good approximation, but certainly not exact with the years. And it depends how many years are we talking about - 2 years or 10 years?

My hesitation with heart rate is that it varies with conditions. With heat, dehydration, overtraining, and other factors, heart rate will differ some, so 182bpm in hot weather vs. cold weather are two slightly different things.

The potential problem I see is the 4mmol. That is the AVERAGE onset blood lactate accumulation (OBLA) point. However, research has reported that OBLA ranges from 2-8mmol/L. So, if you are basing all of your training around 4mmol, and your OBLA is 4mmol, then you should be okay. But if yours is not the average - lets say hypothetically it is 6mmol, then training at the 4mmol pace is not enough.

If nobody else has a good scientific answer for you, let me know - I do running research and I can scour my papers and see what I can find for you, but I believe there is not much published with longitudinal data like these, espcially in elite runners. This is just a quick answer off the top of my head - I can give it some more thought, since I have wrestled with the inter-relationships of lactate, pyruvate, anaerobic/aerobic contributions quite a bit before in doing some of my background research for some projects.

i made a mistake when saying the test was based off of around 4mmol.

the test was run to a point where my lactate levels leveled out and then made a bigger jump. (compared to the previous gradual increases)

Hopefully JT will answer this, but the answer is yes it will change as a function of conditioning and environmental factors such as dehydration, fatigue etc. It is good to know where it is, but the objective is to move your lactate threshold to a higher and higher percent of your maximum heart rate. Under similar environmental conditions etc. when you lose fitness ( injury or periodization), this number will be a lower percent of your maximum heart rate. It is still a useful number because it at present allows you to establish a fitness baseline and know where you are for your immediate training needs as well as it is nice to know in the future as you have a reference for how fit you have been and presumably can be again or even better than.

not the tupper wrote:

...the objective is to move your lactate threshold to a higher and higher percent of your maximum heart rate. ....

Actually, there are two objectives. One is, as you say, to move your lactate threshold to a higher percentage of MHR. But just as important, or more important, is to train your body to hold a faster pace at LT HR. These days, my LT is about 177-178, which is about 90% of my MHR of 199. The goal of my LT runs isn't really to increase my LT to 91% of MHR--or not only to do that--, since 90% is pretty high at LTs go, but to see my pace at 90% of MHR speed up from, say, 7:05 pace to 6:50 pace.

interesting responses....

bumper

You have received some good responses already, and I can't add a lot; especially in terms of recent research. I have a lot of data, but no time to publish so can only tell you what I have seen. Definitely conditions will change the HR associated with a particular speed of running (over slippery or rugged terrain or into or with a wind or up or down hill), and in these cases HR is a good monitor in deciding the intensity of effort you are putting forth. Under desirable conditions (calm, cool day or indoor track) I prefer going by speed of running, which of course can be a fraction of VO2max or fraction of HRmax. When all is well (no wind, no hills, no poor footing), but it is warm, then intensity of effort (speed) is a better factor to go by because the HR will drift upward, and to stick with HR will result in slowing down.

The idea is to have your threshold pace be associated with a higher and higher speed of running. This certainly changes with your state of fitness -- just testing runners in early or late season (or when not able to train because of injury has shown this to be the case). The speed of running associated with "threshold" is also a function of changes in VO2max and economy -- the same fraction of VO2max will correspond to a faster pace if your velocity at VO2max has increased, which of course can be the result of better economy or higher max. Remember the concentration of blood lactate that is measured is a function of how much is being produced and how rapidly it is being cleared, and production depends on energy supplies and needs and clearance improves with training.

As far as using a particular lactate value (4 mmol, for example), this can be useful even if it does not represent your threshold -- a specific blood lactate can still be compared with HR or VO2 or speed of running. As has been pointed out, threshold may correspond to a rather wide range of concentrations – I had a runner repeat miles at a pace that consistently resulted in values in the 7+ range and he was not hurting anymore than another who was in the 3+ range of lactate concentration. Both were running at about the same fraction of HR max and VO2max. In fact, with well-trained runners, I seldom see threshold paces that demand anything outside of about 84-90% of VO2max (a little higher % HR max), and this is a whole lot less variability than using lactate values to determine this, where the range may be 3-7 mmol. By the way, I have not seen any difference when comparing male and female runners – it all seems related to relative intensity of effort, and training does affect things.

Thanks for all the responses.