Expected change in heart rate after training

matthewhenderson

All,

About six weeks ago I performed the Lactate Threshold training described in Chris Carmichael's "Time crunched cyclist". Basically two eight minute all out intervals separated by a ten minute rest period and you take the average of the two average heart rates for those two efforts as the basis for your heart rate zones for training. I then trained for six weeks and repeated the test. In the second test the distance I covered increased in both intervals but my average heart rate went down. In my head I thought I would increase distance and also increase my average heart rate too. If I've interpreted the results correctly I can do more work but my threshold heart rate has dropped. Is this normal? Is it possible that there is another factor at play i.e. fatigue supressing my heart rate? Or are two sets of results just not enough to give a relaible trend? If anybody is a boffin I can provide the Garmin files for interpretation!

Thanks

Matt

cougie

You misunderstand. You've done more distance for less effort.

Your training has paid off - but if you were really pushing yourself you should have been able to hit the same HR as before ? I think you might have backed off slightly ?

I've seen this all along my trainerroad sessions - when I repeat a session from the month before - I'm putting out more power, but at a lower HR.

matthewhenderson

I was thinking I might just not have pushed hard enough. I do each interval blind so reply on perceived exertion so next time need to be less afraid of failure and blowing up entirely!

meanredspider

In some ways it should get harder to reach the higher HR as you get fitter - your cardiovascular system is getting more efficient. You now need to drive yourself harder.

JayKosta

It is common for the max heart rate to actually get a little lower with training.
The heart 'stroke volume' gets larger and the strength of the heart muscle to pump each stroke gets stronger.

This lowering of earlier max heart rate might be 'masked' by an increased tolerance to the pain & stress of the amount of effort needed to reach max heart rate.

In any case, don't worry about it! The training is beneficial. But do make sure you have enough rest & recovery time between high intensity sessions so that you can do the next session at high physical capacity. Otherwise you can just dig yourself deeper & deeper into early exhaustion.

Jay Kosta
Endwell NY USA

andyeb

Also keep in mind that your HR response to a set workout can vary depending on how hard you've been training recently (i.e. residual fatigue) and even differ at different times of day. I find in the evenings, or if I train within 2 hours of eating a large meal, my HR is lower for the same output, my threshold HR is lower (i.e. point where I can only snatch a word between breaths), but my output is about the same.

Whereas I used to train largely to HR, I now use a combination of turbo resistance and speed measured off the back wheels as a proxy for power output. The published power curve of my turbo is linear, so while not perfect, it's good enough.

HR is useful as a training tool, but it has it's limits.

Alex_Simmons/RST

First up, while HR might be a handy indicator of exercise intensity, it is not a measure of fitness.

HR will be affected by many things apart from how hard you are riding, it is subject to day to day variations in response to effort, and it's not accounting for changes in cardiac output / stroke volume that occur as a result of training.

What matters is whether you were able to sustain a higher power output. That's a measure of fitness, HR is not.

If your trainer has consistent repeatable resistance, then the increased distance of your second test indicates an increase in sustained power output. What you won't know is by how much, as the resistance-power relationship for trainers is often curvilinear.

Stalin

Alex_Simmons/RST wrote:

First up, while HR might be a handy indicator of exercise intensity, it is not a measure of fitness.

HR will be affected by many things apart from how hard you are riding, it is subject to day to day variations in response to effort, and it's not accounting for changes in cardiac output / stroke volume that occur as a result of training.

What matters is whether you were able to sustain a higher power output. That's a measure of fitness, HR is not.

If your trainer has consistent repeatable resistance, then the increased distance of your second test indicates an increase in sustained power output. What you won't know is by how much, as the resistance-power relationship for trainers is often curvilinear.

Power is also,affected by many things, temperature, altitude, fatigue, road bike, TT bike, climbing, position, outdoors, indoors on turbo, hydration, glycogen depletion, etc etc.


I'm really fascinated by these people who can increase FTP whilst at the same time generate less watts per heart beat. How do they do this? Do they somehow increase their maximum heart rate or increase their sustainable heart rate closer to their maximum heart rate?

Maximum heart rate actually decreases when you get fit, and there is a limit as to how close to maximum heart rate a mortal can sustain, so sooner or later the only way to improve sustainable power is to increase power:heart rate ratio.

Please explain how you can increase sustainable power without improving power:heart rate ratio.

JayKosta

"Please explain how you can increase sustainable power without improving power:heart rate ratio"

---

I don't think anyone said that!

The ratio of Power:Heart-Rate is somewhat of a 'heart efficiency' indicator, and it relates to the effectiveness of cardio function and capacity.
But the more important goal is 'sustainable power', as you have mentioned.

Jay Kosta
Endwell NY USA

Alex_Simmons/RST

Stalin wrote:

Please explain how you can increase sustainable power without improving power:heart rate ratio.

? Question seems to have gone off the rails, not sure what that has to do with anything.

End of day, if you are not putting out more power for the durations of interest/relevance, you are not fitter, irrespective of what your HR does (higher or lower).

Stalin

Alex_Simmons/RST wrote:

Stalin wrote:

Please explain how you can increase sustainable power without improving power:heart rate ratio.

? Question seems to have gone off the rails, not sure what that has to do with anything.

End of day, if you are not putting out more power for the durations of interest/relevance, you are not fitter, irrespective of what your HR does (higher or lower).

Obviously you are not fitter if you can't put out more power or the same power for longer but I'm interested in people who have managed to do this without increasing their power:heart rate ratio.

We know that maximum heart rate can't be increased, in fact with increased fitness it may reduce. We know that sustainable heart rate can only get so close to maximum heart rate and does not in fact change much with fitness.

How do people increase their FTP without improving their power:heart rate ratio?

Stalin

Alex_Simmons/RST wrote:

Stalin wrote:

Please explain how you can increase sustainable power without improving power:heart rate ratio.

? Question seems to have gone off the rails, not sure what that has to do with anything.

End of day, if you are not putting out more power for the durations of interest/relevance, you are not fitter, irrespective of what your HR does (higher or lower).

Or you have not tried as hard recently. It is entirely possible you are fitter but just less motivated. This is a major flaw in using power alone. The only way you can track improvement is by doing maximal efforts and comparing power to previous maximal efforts. With power alone you have no way of telling if improvements are due to trying harder or improved fitness. People might claim they are not trying harder, they may believe they are not trying harder themselves but how do you know?

Team4Luke

matthewhenderson wrote:

All,

About six weeks ago I performed the Lactate Threshold training described in Chris Carmichael's "Time crunched cyclist". Basically two eight minute all out intervals separated by a ten minute rest period and you take the average of the two average heart rates for those two efforts as the basis for your heart rate zones for training. I then trained for six weeks and repeated the test. In the second test the distance I covered increased in both intervals but my average heart rate went down. In my head I thought I would increase distance and also increase my average heart rate too. If I've interpreted the results correctly I can do more work but my threshold heart rate has dropped. Is this normal? Is it possible that there is another factor at play i.e. fatigue supressing my heart rate? Or are two sets of results just not enough to give a relaible trend? If anybody is a boffin I can provide the Garmin files for interpretation!

Thanks

well done. You have improved merely because you have gone faster and further for less effort involved, you may have been a little tired from other matters, work, sleep previous training and thus possibly have hit a higher ave hr but that all depends on being absolutely accurate as to when you start/stopped you HR monitor, the fact you went further and faster in the same time is the achievement all being repeatable of course on your machine and all set the same. As your not also recording power this result and your lower HR confirms improved fitness. You probably won't make as much or as many gains again.

Matt

JayKosta

Stalin asked
"... How do people increase their FTP without improving their power:heart rate ratio?"

---

Well, I guess they would have to increase their sustainable HR that produces their FTP .
It probably depends on how FTP is being tested / determinded.
If FTP is determined by the amount of power at a particular HR number, then the Power:HR ratio would have to increase if FTP increased.

If FTP is determined by a test of maximum sustained power for a length of time, then the FTP could increase if they were able to sustain a higher HR with the same Power:HR ratio.

What do you think are other possibilities?

Jay Kosta
Endwell NY USA

Stalin

JayKosta wrote:

Stalin asked
"... How do people increase their FTP without improving their power:heart rate ratio?"

---

Well, I guess they would have to increase their sustainable HR that produces their FTP .
It probably depends on how FTP is being tested / determinded.
If FTP is determined by the amount of power at a particular HR number, then the Power:HR ratio would have to increase if FTP increased.

If FTP is determined by a test of maximum sustained power for a length of time, then the FTP could increase if they were able to sustain a higher HR with the same Power:HR ratio.

What do you think are other possibilities?

Jay Kosta
Endwell NY USA

Fact is you can only increase your sustainable heart rate so far, you can't really increase it. You might if you are a beginner. But it remains pretty constant. So you only have one way to go and that is more watts per heart beat.