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Discussion Starter · #1 ·
DISCLAIMER:
I do not own a powermeter and have no plans to invest in one in the immediate future. I use HR with all of its imprecision, and PE (perceived exertion) A.K.A. 'the Force' I am aware of the advantages that power based training has!


Last year in early season testing I determined my threshold HR to be 152 bpm using the Friel method of taking the average HR from the final 20 minutes of a 30 minute time-trial.

Reviewed my HR monitor data after the last race of the season (two weeks ago) and noticed that my average HR = 169 (max = 180). The race duration was 1:36.
Previous race avg. HR = 165; max = 180; duration=1:20. Both of these races were flat, no significant time spent climbing or descending, the weather was getting cold for them both as well.

Looking further back in the 2009 season I saw my HR varied quite a bit in other TT or races from mid-summer onwards.

For example:
40K TT - 155 bpm (~70 minutes)
5 mile TT - 170 (~13 min)
hill climb TT - 162 (~16 min)
MTB hill climb TT - 174 (~17 min)


QUESTIONS:
Should I use the race results to base my HR zones? (Would be a fairly large increase)
Is there a factor I might include to adjust the threshold HR based on races or colder weather?
Is it a good thing that my threshold HR has increased? (Think I know the answer but wonder what others would say)
 

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mutaullyassuredsuffering
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ebay

I know you don't want to hear it but...I gave on using HR 2 years ago due to the same issue. My HR is just too variable to use as an effective tool. I found a power meter real cheap on ebay for the road bike and it's completely changed my training. I can guage my PE well enough to avoid buying a MTB version.
 

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No. Just No.
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NC2WA said:
Last year in early season testing I determined my threshold HR to be 152 bpm using the Friel method of taking the average HR from the final 20 minutes of a 30 minute time-trial.

Reviewed my HR monitor data after the last race of the season (two weeks ago) and noticed that my average HR = 169 (max = 180). The race duration was 1:36.
Previous race avg. HR = 165; max = 180; duration=1:20.
Many people, myself included, find in-race HR (especially on trails) to be inflated versus HR derived from a road test. Adrenaline and different physical requirements of racing on trails with more muscle groups being recruited than a road TT as potential causes.

Your "threshold" HR may indeed have increased, which is usually a positive thing assuming it is accompanied by an increase in output/power/watts, but using one observed HR for the other purpose may not be relevant. Perhaps instead consider retesting using same protocol, and then use that figure as a basis for training sessions, but not racing, or vice versa.
 

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Characteristics of a good LTHR test:

-Even, maximal effort over very few gear changes
-Minimal or no coasting or standing
-No sprints or spikes in power
-Fairly constant RPM


Races never really have those characteristics. Spikes in HR with corresponding HR lag will always give an artificially high LTHR result (and lowest LT power, BTW; for me at least).

Also, the more an outdoor test has those characteristics, the better match you will have to an indoor test. Need a really, really flat road.
 

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used2Bhard said:
I know you don't want to hear it but...I gave on using HR 2 years ago due to the same issue. My HR is just too variable to use as an effective tool. I found a power meter real cheap on ebay for the road bike and it's completely changed my training. I can guage my PE well enough to avoid buying a MTB version.
HR is directly related to the lactic acid buildup in your muscles, per one of the worlds foremost sports physiologists, he would prefer HR only training vs power only. Power is a great tool to measure your lactic acid processing at a given power output...ie your HR. While I love my power meter too, its truly not the end all be all device it was originally marketed as. Its a great supplement for training but shouldn't be the only thing you use.
 

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Discussion Starter · #8 ·
used2Bhard said:
I know you don't want to hear it but...I gave on using HR 2 years ago due to the same issue. My HR is just too variable to use as an effective tool. I found a power meter real cheap on ebay for the road bike and it's completely changed my training. I can guage my PE well enough to avoid buying a MTB version.
I know, I know...I am waiting for these!

http://www.metrigear.com/products/

Read that the release date has slipped to Q2 2010 or beyond.
 

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Discussion Starter · #10 ·
Circlip said:
Many people, myself included, find in-race HR (especially on trails) to be inflated versus HR derived from a road test. Adrenaline and different physical requirements of racing on trails with more muscle groups being recruited than a road TT as potential causes.
I actually had written a question down about differences in HR between Road vs. MTB, but thought it was a tangent.

Circlip said:
Your "threshold" HR may indeed have increased, which is usually a positive thing assuming it is accompanied by an increase in output/power/watts, but using one observed HR for the other purpose may not be relevant. Perhaps instead consider retesting using same protocol, and then use that figure as a basis for training sessions, but not racing, or vice versa.
Good advice to re-test.
BTW, the increased "threshold" HR has been accompanied with better results, increased fitness, and a class upgrade. For instance, my time on that MTB time trial decreased by around two minutes from last year's.
 

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NC2WA said:
I actually had written a question down about differences in HR between Road vs. MTB, but thought it was a tangent.
It's not that HR from road cannot ever be compared to HR from MT, but see other reply from Poncharelli which lists some reasons why in many cases the 2 are different enough activities with different profiles of physilogical stresses that make direct comparison difficult.

NC2WA said:
Good advice to re-test.
BTW, the increased "threshold" HR has been accompanied with better results, increased fitness, and a class upgrade. For instance, my time on that MTB time trial decreased by around two minutes from last year's.
Capabilities and results are the important criteria. If you find that your HR response is the same as before don't worry about it, since the evidence you describe still suggests that you are in better condition. Although I don't have any documentation to back this up, I suspect that once a person reaches a relatively advanced state of fitness their threshold HR won't change very much afterwards even if they subsequently continue to improve performance. From that point onwards it's real output which continues to climb for same HR levels.
 

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fsrftc said:
I've noticed that altitude effects my hr somewhere about 1/2-3/4 beat per minute higher per 1000 feet in elevation gain. I simply cannot match my high altitude HR averages at a relatively low elevation where I live.
I see the opposite trend. In high altitude races I never come close to the max or avg HR seen at lower altitudes; RPE always seems just as high. My theory is I can't get enough oxygen to my muscles for them to work hard enough to see a high HR.
 

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You also might have had a "bad" test when you performed the LTHR test for various reasons. Maybe you were not well rested. Maybe you were slightly under the weather. Maybe you were under stress due to work or other stuff. Maybe the heart rate monitor didn't work too well. I think you ought to repeat the testing since your result seems a little off from your race heart rates and and you've been through a season of racing anyway.
 

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As stated below, LT changes in reasonably trained athletes are usually small.

Is last year’s early season test the only one you've done? Was the 152 result high, low, avg? Sounds like you should definitely retest. Now that you know you’re capable of 165-169, push yourself for that.
 

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My two cents: Retest with same test as before (avg HR of final 20mins of 30min TT). Test in your training conditions (if your training outside, test outside; if training inside, test inside).

Your HR varied in different circumstances in part because many things (other than your actual intensity level) can affect HR. Also, it's not uncommon for MTB hill climb to have higher HR than road hill climb (I believe it's because off-raod terrain causes you to use more muscles to juke/manuver the bike around and because dirt has more friction which requires very slightly more acceleration on each stroke).
 

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stillhardtailing said:
I see the opposite trend. In high altitude races I never come close to the max or avg HR seen at lower altitudes; RPE always seems just as high. My theory is I can't get enough oxygen to my muscles for them to work hard enough to see a high HR.
you're doing it wrong ;)

seriously though...at low elevAtions your blood is more oxygen rich therefore your heart doesnt need to beAt as fast to supply the amount of oxygen your muscles need. When I was at sea level briefly to train my breathing was never Labored even on speed/hill work (I did not have my hr monitor with me), but my observAtions were correctly confirmed by a physiologist. You should power train at lower elevations because of this. Your hr is elevated at altitude to compensate for the diminished oxygen in the air. If you can't hit your low altitude hr or more at higher elevations I would think u aren't pushing yourself or you need to do some v02 work, the latter being speculation. I'd try to talk to a sports physiologist if I were you. I also think PE is skewed at higher elevations.
 

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mutaullyassuredsuffering
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Altitude

fsrftc said:
you're doing it wrong ;)

seriously though...at low elevAtions your blood is more oxygen rich therefore your heart doesnt need to beAt as fast to supply the amount of oxygen your muscles need. When I was at sea level briefly to train my breathing was never Labored even on speed/hill work (I did not have my hr monitor with me), but my observAtions were correctly confirmed by a physiologist. You should power train at lower elevations because of this. Your hr is elevated at altitude to compensate for the diminished oxygen in the air. If you can't hit your low altitude hr or more at higher elevations I would think u aren't pushing yourself or you need to do some v02 work, the latter being speculation. I'd try to talk to a sports physiologist if I were you. I also think PE is skewed at higher elevations.
Yup. I can see this when I ride from my house to the top of Mt Evans (14,000') and when my coach comes up from Michigan to ride with our group. In both cases the HR stays consistent but power continues to drop with altitude. It is a good scenario when I do use HR, as power becomes useless when I gain 8,000 of altitude during a ride and when my coach gains 7,000 feet and comes to my place.

I can still judge my PE pretty well, as I can tell that my legs aren't generating as much power.
 
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