Today's comparison Charge HR output against Runkeeper

W_Stewart · April 2015

I realize I'm not comparing apples to apples here, but I did want to see if the Charge HR heartrate output paralleled the elevation output tracked by Runkeeper on my morning trail walk. I walked it pretty hard (for me).

Runkeeper, which uses GPS on my iPhone to know the elevation and speed:

Charge HR which should be using my heartrate:

SOLka3B.png?1

And this is another view of the 2 main charts I am comparing: Chart HR on top, elevation underneath. To me the heartrate output more or less follows the expected increase/decrease as I trudged up and down those hills. I don't expect them to be perfect as my heartrate probably stays up a bit even though I have started to go down a hill.

RnbyrZZ.png?1

I was watching my iPhone HR output in the Fitbit app as I had the All-Day Sync feature enabled. Many times (too many) the watch and app lost my heartrate even though I am wearing it properly and it seems to track consistently when my heartrate is at rest. Increased heartrate seems to increase the frequency of losing track.

The calories are quite different, not sure which to believe. Right now I am sticking with Runkeeper's output and letting it update MFP for exercise activity since I still see too many abherations with the Charge HR output. I'm hoping to get to a point where I can trust it better. Today's test/charts make me feel a little better, but the good sort of balanced out by the periods where it lost signal at activity levels I really wanted tracked better.

Which calorie burn would you use?

heybales · April 2015

So you got me curious, I'd off hand trust RK more, not only because the Charge lost HR for some time, but also because it may be using assumptions for you that are not best.

So I wanted to see if I could run the calc's found best for accuracy against your data, which I have to make some assumptions on.
Assuming the elevation gain and loss 319 is the same, which it should be.
That it took the same amount of distance 0.97 miles for both, which I can tell isn't true, but probably close enough.
That it took the same amount of time 17:25 for both the ascending and descending parts, but probably walked faster downhill, but maybe close enough.
That your resting calorie burn is same as my stats, 1.20 cal/min.

268 calories

For your calculation, 268 / 1.20 / 34.83 min = 6.412 METS

So find your resting calorie burn in your daily 5 min graph for a 5 min block of non-moving time, should match sleeping time. Divide by 5 for per minute calorie burn.

Your resting calorie burn x 6.412 x 34.83 min = calories for walk.

This is walking formula found best in study, with correction for walking downhill figured in.

W_Stewart · April 2015

I don't follow why you calculated a MET value rather than using a standard MET value to calculate the calories burned?

heybales · April 2015

Because you have hills up and down, and your pace doesn't match the ranges in the databases exactly.

Though, using total time, grade of 6.23%, pace of 3.34, it does work out to 6.4 METS in standard calculator.
But the times of up and down hill can make a difference.

But indeed, close enough perhaps.

W_Stewart · April 2015

Losing HR appears to be a repeating issue for me. Today I went on an hour long walk and kept a steady 4 mph pace. I kept the All-Day Sync feature on and kept watching the output on my iPhone. Probably 30% of the time I looked down I saw the -- dashes indicating it lost HR. And today was my test of running it higher up on my arm. I used a rubber band to hold it half way between wrist and elbow. Didn't seem to make any improvement.

heybales · April 2015

Yep, some people it doesn't work well on at all.

You are on the bottom of the bell curve, but at least not at the trailing end where it fails at reading HR during daily activities. Some have reported they are.

Few others have reported testing intense exercise along with Polar, and except for lag time to report the same HR, it reached the max they normally get in intense exercise - so other side of the well curve.

W_Stewart · April 2015

Thanks for all your help. You have really bent over backwards to explain things to me and I appreciate it.

heybales · April 2015

I think these are good realizations for others reading too - may not work for all.

For some that have never used a HRM and have no idea how high HR used to get, they may not even know it's not reading well unless they see those level spots during a workout.
But if it's just reading low, they'd never know.

Then again, they may be doing an exercise intensity and frequency that the inaccuracy really doesn't matter, because the most they do is walk.

But you have goal you want to reach that include going harder and longer it sounds like, and issues now mean bad news later.

Wolfe1965 · May 2015

I have found in my brief testing that the CHarge HR is within a few beats per minute for most activities. For things like yard work, fitness machines and non mountain biking it does ok. The advantage over a heart rate only solution is it also has step data, and possibility GPS data to use when HR data might not be the best measure.

When I am doing pretty strenous cardio, where I know HR is th best measure of calorie burn I still use my chest strap and port the data to fitbit via MFP. I was pleasantly surprised to learn that the heart rate data actually makes it to fitbit, when I am using MFP as a go between application since the app I normally use, wahoo fitness doesn't port directly to fitbit as of yet, but does to both MFP and Garmin connect which both port the activity to fitbit.

heybales · May 2015

Where did you hear the HR data makes it in to MFP, and then is sent on to Fitbit to replace what it saw?

Or/And you have MFP and Garmin both syncing the same workout to Fitbit?

Have you looked at your Fitbit Log - Activities page to see if double workouts are ending up there?

Fitbit Users

Today's comparison Charge HR output against Runkeeper

Replies

Categories