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Calculating heart rate #'s. ??(9 posts)

Calculating heart rate #'s. ??Psychler
May 22, 2002 9:43 AM
A friend just bought herself a treadmill...she wants to use her heart rate to pace herself. How do we calculate her max.? Obviously her max, a 50 year old woman who has not done any exerceise for the past 20 years, will not be the same as mine ( male, 50, rides 4x week). Will knowing her resting heart rate help?
For a rough estimate... (but she needs a physical)cory
May 22, 2002 11:00 AM
There are newer and more scientific methods of doing it now, but one that was popular for years was to figure the max as 220 minus her age, and the exercise range as 60 percent to 80 percent of that. So her max would be 170, and she'd train at between 102 and 136. Low end is safer at first, of course. But at that age, and especially since she hasn't exercised, she really should have a physical and probably a treadmill before she starts.
wait, wait, wait. Relative fitness does not define your max.bill
May 22, 2002 11:34 AM
It is what it is; it's genetic, mostly. I ride with a guy who is about my age, probably a little less cycling fit than I am (if who gets to the top first is any indication), and his max HR is a good 20 ticks higher than mine (from my lactate threshold, calculated imperfectly, with some corroboration from the highest HR I've ever seen on my monitor, 189, compared to his highest, which he says is about 210). Even lactate threshoold as a percentage of max is an estimate and not precise, which can be determined only through laboratory tests and can be increased. Just for an anecdotal reference, when we're cruising, his HR is about 165 where mine might be 140. I'm not sure what his resting HR, which does seem to relate to fitness, is, either, but I'm sure it's not 20 ticks higher than my 55-60 bpm (I'm not sure what mine is, but it's in there somewhere).
I also have DEEP concern about her being away from exercise and then stroking out trying to learn her max HR. Not only is it dangerous, but her max HR has almost nothing to do with the kind of working out she should be doing at this stage.
She should spend some quality time with her machine at an effort level she can maintain with a little huffing and puffing for about twenty minutes or half an hour. Then, come back in a month or two and we'll talk.
current standards (geek alert)theBreeze
May 22, 2002 12:08 PM
220-age is still the standard way of estimating max HR. VO2 max and lactate threshold depend upon fitness level, max HR does not. The only true way to determine max HR is to do a maximal graded exercise test, which should only be done under a doctor's supervision.

You can be a little more precise in determining target exercise range by using the Karvonen equation;
1.) (220-age) - resting HR = Heart rate reserve (HRR)
2.) take 60%-80% of HRR and add to resting HR to get target heart rate range.

For someone starting a program I would recommend staying in the 60% level for about 20 minutes per session. Include a 5 min warm up and cool down.

If she really wants to know what her current fitness level is she can get a fitness evaluation at her local YMCA for about 25-30 bucks. Includes a submaximal aerobic test (usually cycle ergometer), body composition, muscle strength and endurance (timed half-sit up and bench press) and flexibility. They may require a clearance from her MD depending on her medical history, but not just because she is 50 years old. We only require a medical release based soley on age for women over 55.

(BTW, I do this for a living.)
I did a survey here, analyzed the results ...Humma Hah
May 22, 2002 2:52 PM
Based on a survey of 37 riders on this forum, and an extensive analysis of the data (OK, I plotted it with Excel and tried a few curve fits), I determined conclusively that all formulae for calculating max HR are crap. The best fit would get you to about +/- 20 beats per minute.

One interesting observation, very few of the younger riders reported max HR anywhere near those predicted by the formulae. They were way low. The problem, I think, is that young riders have rarely had a cardiologist's treadmill stress test, and have never actually come anywhere NEAR their max HR! (Reaching max is PROFOUNDLY unpleasant, and few people will do it unless forced to).

The old guys who had numbers from a cardiologist were typically ABOVE the max HR predicted by the formulae. The popular formulae are written by lawyers, and conservative.

Bottom line: wanna know the number, see a cardiologist.
I did a survey here, analyzed the results ...theBreeze
May 22, 2002 6:13 PM
A survey of 37 riders is a little small to state that decades of exercise physiology research is crap.

You are right that "self-imposed" max HR numbers are going to be low. True max tests ARE very unpleasant. In the old days they strapped people into a harness for the test because they kept the treadmill going until the testee literally fell off the back and was caught by the harness.

The "popular" formulas were NOT written by lawyers and conservatives, but based on real exercise phys research. It is applicable to the general population and does carry a +/- of about 10%, which fitness specialists and exercise physiologists recognize.

An individual can get "their" max HR number by getting tested by a cardiologist, but the 220-age is still plenty good enought to train with. As a person gets more experience training he/she can tell how hard they can push, or how to go easy. Assuming one's predicted 80% max HR is 5-6 bpm higher or lower that than the "true" number is not going to significantly detract from any training effect. Perceived exertion is just as important, maybe even more so for those with a lot of training experience. Don't get hung up on any "magic" number.
May 23, 2002 3:53 AM
ive read several studies (sorry, cant quote them, it was from magazines years ago - probably RW or Triathlete) which indicate only 50 percent of all people are within 10 percent of 220-age.

Of other note, isnt the formula for women like 225 or 230 minus age?
The one I loved was the survey of the resting heart rates. Ofbill
May 22, 2002 6:58 PM
the twenty or thirty people who responded, the average was like, oh, low forties, with a substantial number reporting in the thirties. When one wag reported that the average resting heart rate of the guys on the tour (his numbers were, I'm sure, as specious as all the others) was a good 5 beats higher than the average sampling of contributors, I about wet my pants.
Stop.Len J
May 23, 2002 4:12 AM
Before you read this you should know that it is ultra conservative.

How much does she currently exercise? If little ("50 year old woman who has not done any exerceise for the past 20 years'), she definatly should see a doctor before she starts. No one here can give meaningful advice without knowing her base physical capability.

The 220 - age formula is crap, especially for someone like your friend. I am 47, formula would say that my max is 173, my max is (tested) at 198, my LT is around 180, I can ride all day at 170. I have a riding buddy who is 50. His tested max is 160. You see the problem.

I would recommend that she: 1.) see a doctor & get some advice. 2.) start out slow on the treadmill, walking for short periods. gradually build up time & intensity, use how it feels as an indicator of effort & use the HR monitor to begin to understand that her legs hurt at "this effort & at this heartrate". If she hasn't exercised in 20 years, she should be worried, not just about pushing her heart to much, but also pushing the rest of her. Her body will have to get used to the stress of exercise. In my oponion, one of the reasons people abandon exercise programs is that they push themselves too hard too early & develop "nagging" minor injuries. If she is trying to "exercise for life" patients now will pay off in the long run.

My .02


P.S. Resting HR is a measure of cardio fitness however it is a better measure of improvements in your own fitness than compared to anyone else. (I.e. as one gets into better shape, thier resting HR should decline)