Calculating Target Heart Zone While Using Beta Blockers

[Jack]

The usual calculation is 220 minus age X 50-85%.

Literature, including that from the Amer. Heart Assn. is very
vague on this subject when beta blockers enter the picture. It
would seem to me that your resting heart rate should be used
in the calculation. In fact, your resting heart rate is never
used in calculating target heart range, even people not using
beta blockade.

Researched the Internet and the most detailed guidance I could
find said that people on beta blockers should undergo a
treadmill exercise test to determine target heart range.

1) Why is cardiac science so generic (220 minus age X
50-85%) for people not on betas, yet so specific for
those using betas?

2) And why is an individual's resting heart rate never
considered?

[joeu2004]

Jack wrote:
> In fact, your resting heart rate is never used in
> calculating target heart range, even people not using beta
> blockade. [....]
> 1) Why is cardiac science so generic (220 minus age X
> 50-85%) for people not on betas, yet so specific for
> those using betas?
>
> 2) And why is an individual's resting heart rate never
> considered?

The simple answer to the latter question is: do a google
search for "Karvonen". You will find that the resting HR is
not "never considered".

(But caveat emptor: Karvonen was developed by statistical
analysis of data for highly-athletic individuals. The purpose
of Karvonen is to raise their performance. It might not be
appropriate for people whose heart rate is adversely affected
by medication.)

The general answer to your questions is: there is an attempt
to simplify -- to the extent of oversimplification. In fact,
many age-based formulas have been derived by statistical
analysis and linear regression. Some formulas incorporate
gender. "220 - age" was merely the first. Recent analysis
suggests that it is not the best. But all of the formulas are
close in their results, and all are equally inaccurate. "220 -
age" is used so pervasively largely because of its simplicity.

Finally, it is widely known that the only way to determine
your true MHR is to have a maximal stress test under clinical
conditions, which typically involves the use of a treadmill.
That suggestion has never been specific to or limited to
people on beta blockers. What might be specific to beta
blocker users -- but probably also users of a lot of other
medications -- is that the age-based formulas are even more
inapplicable to them. I have not heard that myself; but I
would not be surprised if it were true.

(The age-based formulas are based on data derived from
mostly-healthy sample groups, although some samplings
specifically target over-fat individuals to one degree
or another.)

In any case, the three main reasons why people do not take the
trouble to get a maximal stress test are: (1) cost; (2)
inconvenience; and (3) risk. It is usually sufficient to use a
combination of HR monitoring and "listening to your body" (aka
"perceived exertion"). Generally, only people with known heart
health risks and serious athletes need to bother with maximal
stress tests.

[Steve Frei]

"Jack" <windswept@home.net> wrote in message
news:45264451.2790843@news-60.giganews.com...
> The usual calculation is 220 minus age X 50-85%.
>
> Literature, including that from the Amer. Heart Assn. is
> very vague on this subject when beta blockers enter the
> picture. It would seem to me that your resting heart rate
> should be used in the calculation. In fact, your resting
> heart rate is never used in calculating target heart range,
> even people not using beta blockade.
>
> Researched the Internet and the most detailed guidance I
> could find said that people on beta blockers should undergo
> a treadmill exercise test to determine target heart range.
>
> 1) Why is cardiac science so generic (220 minus age X
> 50-85%) for people not on betas, yet so specific for
> those using betas?
>
> 2) And why is an individual's resting heart rate never
> considered?

My admittedly limited understanding of beta blockers is that
individual reactions to them vary so much that no formula is
even possible, and the formulas aren't even all that great for
people who don't take beta blockers. E.g., the way you
approach whatever your maximum is will be different, and
therefore training at a particular percentage won't mean the
same thing as to a person not taking the same drugs.

Percentage of MHR training is simply not necessary for the
overwhelming majority of the exercising population. Many
people, me included, have achieved very good results from
following sensible training advice and schedules. You are best
off to go by perceived exertion.

Resting heart rate is not a factor here, which is why it is
not considered. Those wishing to train based on a percentage
of MHR need to determine what their MHR actually is and, even
then, the percentages that work best vary slightly from person
to person.

If you say a bit more about your background, your current
height, weight, age, sex, etc., plus any recent athletic
accomplishments if you have them and/or a training
history of some sort, we might be able to offer some more
specific advice.

-S- http://www.kbnj.com