How low do you go?....

OK, I'm 44y.o., soon to notch up another one. I exercise most days so it's difficult to get a genuine RHR. With a couple of days rest I can go as low as 38/39. Usually it's around 42-44.

It counts for nothing, but post-operation in recovery the nurse was annoyed at having to reset her monitoring machine alarm so many times as I was hitting 32. There's a technical name for this and it has nothing to do with fitness, more to do with drugs.

Some people have large (volume) hearts, some people have smaller/ faster hearts. Although exercise can increase heart volume, there is no direct correlation with fitness. There are plenty of very fit people who don't have low RHRs and can comfortably exercise with their HR well over 200. The only really meaningful number is what happens to your own HR over time - does the RHR come down or go up?

39yrs old RHR of 40 to 42.  I was told that if it fluctuates more than 3 beats whilst being taken in the same circumstances it can indicate overtraining or impending illness, has anyone else ever heard of this?

I have the Heart Rate app on iPhone and have been doing some tests with it with people at work on various other apps. To be fair they seem fairly consistent.

Yesterday, as soon as I woke up I took my heart rate and it was 50; it avergaed out at 51 over the course of the day. Last night I went for a 8 mile run. This morning I have taken my hear rtae again and it is so far averaging 60 over about a 2 hour period.

Can I expect to see such fluctuations ?

I've never thought much about it, but I've always known I seem to have a low heart rate. But just read a little, having seen this thread, and I'm not sure what to think.

Wikipedia says that the RHR is taken when the person is rested but awake. I know that I've laid in bed after a night's sleep, and quite often measured it at 30-32, even known my drop to 29 on occasion. But mid to high thirties is much more typical.  During the day, HR is normally about 55-65 (just took it now, and it's 50, but I've not done much yet).

Seems to be a natural figure, because I got quite unfit a few years ago, and still had these sorts of low resting heart rates.

If I believe Wikipedia http://en.wikipedia.org/wiki/Heart_rate#Resting_heart_rate  then I should expect a proper athlete of my age (48) should have a RHR of between 50 and 57.  But that figure is a long way from me (a below average club runner)... and a long way from a lot of people on here.  So...  when should RHR REALLY be measured?     If I take my  HR now, sat around having not done much other than take breakfast and do a few things this morning), then it's 50, and sounds more realistic. 

So what is the way of measuring?  And what results should we expect?

First thing in the morning, a few days in a row and take an average. If there's a measurement a few beats higher, throw it out as an outlier indicating tiredness from training, infection or something. As TD pointed out, the RHR in itself is not a particularly good indication of fitness, though there's a correlation. A better indication is what the RHR was before you started training vs. what you get it down to after training for days, weeks or years, i.e., the delta not the absolute.

Hell Steve... if it's the delta that's important, mine will have to be close stopping to indicate I've got really fit

When you say 'first thing in the morning'  -  Do you mean like FIRST thing.  whilst lying in bed and barely having moved?

Having written the above sentence, I just did an experiment.  I had my laptop on lap, sat up with legs up on the sofa. Heart rate 38.  I  just moved a little, to put my feet on the floor, still sat down.  I measured 40.  I slowly stood up, and waited quietly for a minute - then measured 47.  Then lay down flat on the floor, waited a minute, and it was back down at 41.

From this (not very scientific) experiment, I'd suggest that HR is affected a lot by whether or not your heart has to fight gravity, to get blood to and from your extremities.  The last reading (laid flat) should theoretically have been the lowest, but could be within normal scatter of results or (likely) affected by me not resting long enough after getting myself in position.

So measuring just after you've got up, could give a very different result than if you measure just before you get up.

I'm 39 my resting heartrate is 60-62. I thought that was rather good until I saw some other on here! but I am an ex smoker so maybe that has something to do with it?

H/R taken at Docs. yesterday, 46bpm.( Annual check-up.) I'll be 68 in November but I have been running over 40yrs.

When you adjust for heart rate reserve instead of HR max in training zones (one possible use for RHR) a couple of beats doesn't make much difference, so you don't need to sweat it too much, but yes, the std advice is to do it lying down, before you do anything or have drunk coffee, read the Sun, or whatever.

Example:

• 87% of my max HR = 168.8
• 87% of my HRR given 44 RHR = 174.5
• 87% of my HRR given 42 RHR = 174.2

IOW If I want to train near threshold, failing to take into account my resting heart rate is a much bigger error (6 bpm) that being a bit inaccurate with my resting heart rate.

Run Wales - Similar here. Mine is about 33/34 on average if I lay in bed a little while. If I take it now it is 46. Mid forties is about the norm during the day if take whilst sat stationary.

Good point Steve C - I wish I knew what mine was 2 years ago!

There was a nice training section discussing heart rate training and how to find your resting, tempo and max heart rate on Marathon talk a few months back. Episode 125 about 45 minutes in.

RHR 48 this morning. Has been consistently ~54 for the last 2 months, so not sure why the drop today.