Power and Heart Rate: checks and balances

hollow_r

Began power this November OS.  Currently finishing first VO2 max week, #9, I believe.

I'm noticing, as the weeks pass, a trend for both Threshold and VO2 max intervals (at prescribed power, based on FTP test) to not generate the same and rather previously consistent heart rate for those zones.  I'm wondering if maybe I dogged it somewhat on the tests and really should be pushing harder to also hit somewhere near the expected heart rate zones (as a check and balance sort of thing) or just ignore heart rate and use the power numbers as is?  I understand the heart rate lag factor, but even at steady efforts and longer trainer intervals this finding seems to hold.

Prior to power and through various calculations and loose tests I had estimated my FT HR at about 155.  After I bought the EN plans last year and pseudo followed them (with HR alone) I did one 40' FT test and got a rate of 139 but I really believe this was way off.   I say that because I can ride for hours outside at 139 with none of the pain of the work at my previously estimated FT HR.   By the way, this year, I've been consistent, having tested and training on the Lemond Revolution.  None of the data below is from outside rides.

The question is:  Should my Hr zones hang with my power zones reasonably so over the OS?

Maybe it makes a difference but doing almost all bike and no run while recovering from hip tendonitis:  4 and occasionally 5 bike OS workouts per week.

Here's the data I've seen that makes me suspicious.

First FTP test 209 with Av Hr of 153.  Seemed about right.

Beginning of OS early and mid November Threshold intervals 1.04 - 1.05 with Hr@150ish, seemed about right.

Later in Nov and early Dec: Threshold Interval IF 's:

1.08 @145      1.1@152         

1.02 @145      1.024@149     

1.11@149       1.025@148

1.04@141        .98@144

1.04@148      1.025@146

1.04@142       1.035@142

The above seem to be trending to lower Hr at higher than prescribed power.

Week 8 FTP test 222 with Av Hr of 149.  (Again first test 209 @153) Think I maybe spent too much time watching the watts as opposed to really pushing.

Did not find it hard to bump up to the new numbers for this tested  FTP

Since test:

1.06@143    1.05@151

VO2 max (2.5' on 2.5'off):  

1.26@142  1.26@142  1.31@149  1.40@156   On these last 2 I purposely pushed the interval to try and get Z5 Hr                                    

1.26@136  1.43@144  1.26@141  1.23@147

Yesterday:  Threshold intervals:  1.02@134  .99@138     VO2 max intervals 2.5 on 2.5 off:  1.26@141  1.31@141

Sorry for the mind numbing data.  

In summary, before power I would kill myself to get my Hr into the Z4 and Z5 ranges and hold the interval times no matter what.  Now, it seems that if I hold my power at 95-100%  or 120% for the corresponding intervals I rarely, except maybe the last interval get close to the heart rate zone, even on a 15 minute threshold interval.

This makes me suspicious that my testing does not reflect the kind of effort required.

I do think that my Hr zones correlate reasonably well with my best guess at RPE.  Still working on RPE interpretation.  I'm just kind of concerned that at the end of the day right now I'd be training harder using Hr alone than I would with power.  So I've been using Hr as a check and balance.   Maybe I shouldn't be looking at AvHr and rather MaxHr for the intervals, but even that seems a little low.

Any thoughts?

 

 

 

John Withrow

First thought is that work works. Power data doesn't lie, so higher power at a lower HR means you're gaining fitness which is a good thing. I have a similar problem that my heart and lungs are in better shape than my legs are so my wimpy legs is my limiting factor in pushing the watts, not my HR. With that said, once I got power I only give casual glances at my HR if I even remember to wear my HRM. I use this as more of a sanity check and have never actually compared one to the other. If you were trying to compare the two though, I would think that only the max HR on short sets would even come close to being comparable since there will likely be a pretty big difference between average and max.

The VO2 sets should seem really, really hard. If they feel easy then you most likely underperformed on your 2nd FTP test. You still had a nice bump, but I would guess that your assessment is right in that you limited yourself by staring at watts instead of just pushing until you wanted to puke. You can either retest your FTP, or do what many will do and just swag it up a bit. Be cautious if swagging your FTP up though. Remember that a lot of the fatigue in these sets is cumulative (especially with your extra bike workouts) and it could hit you pretty hard in a couple of weeks.

Al Truscott

Rick ... John's right. While it may be true that you could work a little harder on the tests, your data confirms that you are gaining substantial improvements in fitness. Your muscles literally are requiring less oxygen to do the same work, so your HR goes down at a given power level. Probably you are recruiting muscle fibers you hadn't been using all that much. Remember that the FTP intervals can be effective at the range of 95 a 100%. So even if your FTP were 5% higher, you'd still be doing the right work in your OS FTP interval sessions at the power levels you report. Since you are showing consistent ongoing improvement and are not feeling any chronic fatigue,I'd suggest keeping the same FTP, and just working like you have been until next test. For your VO2 intervals,just keep blowing them out like you have been.

David Ambrose

Rick - Al is right on. I also like to calculate a stat (power divided by HR) for each workout. I'm not sure if it has any true scientific worthiness, but for my personal experience, if that stat is rising over time, then it does seem to correlate to improved fitness level, at least in terms of one's aerobic engine capacity --- i.e. I'm pushing more watts and is not taking a whole lot more heartbeats to do it ---- a good thing, or I'm pushing same watts (e.g. FTP) but now taking less heartbeats to do it ----- also a good thing. Both situations indicate improved fitness.

jhbinsc

The best thing about power is you can ignore HR data which LIES frequently! Many reasons your HR can decline as fitness increases, too numerous to mention here. Check wiki.

Go exclusively w/ power and NO SWAGing. Use test data until you EARN a higher FTP. Some people feel VO2 work feels "easier" than FTP but can burn you to a crisp pretty quickly. It is still December, plenty of time to improve your #'s just don't want to burn out in Jan. Keep doing the OS as #workworks!

hollow_r

Thanks to the Vets and WSMs. Good to have wisdom and willingness to share it in one place. I read everything you guys write (here and around the site) and I feel like it's advice from a trusted old friend; that's rhetorical only, Al.