Inaccurate HR Reading -- SOLVED

[tractorlegs]

I received the Charge HR for my birthday and could not be happier. I've lost almost 10 pounds in my first month of use.

I've discovered that when I am at rest, or at night, the HR tracker is very accurate. When I take my pulse at my wrist or at my carotid, it always matches what the Charge reports. However, during exercise (aerobic walking) it becomes very inaccurate. Generally, I walk at about 110 BPM (checked accurately at the wrist or carotid) however the tracker reports high 80s or low 90s. Documentation for the device says to move it further up my arm to 3 finger widths above the wrist bone to get a more accurate reading, however that does not change the results. Pro reviews of this device indicate that this problem is not uncommon. How can we increase the device's accuracy when exercising?

[tractorlegs · Accepted solution]

I have an idea that I will try the next time I walk. I'm going to wear the device so that the HR led lights are on the bottom of my wrist, instead of on top. There's less hair, less "tan", etc. and my skin seems less opaque underneath the wrist. I'll report back . . . . 

[tractorlegs]

I did it - Turned around the ChargeHR so that the LEDs faced the bottom of my wrist instead of the top, and did a 40 minute aerobic walk at 105 to 110 BPM and compared my HR at the carotid with the readings from the tracker, and the tracker was accurate within 1 or 2 bpm. I did the comparisons 4 or 5 times throughout the walk.

I'm 63 yoa with a max HR of 147 (stress tested) so my 105 to 110 range is aerobic for me, however young folks with high maximum HRs - I don't know how these trackers work up in your range, but for my purposes problem solved.

[StephenB427]

I'm an age 68 light skinned/haired male with similar Charge HR problems and I don't really understand when you say the LEDs face the bottom of your wrist. The two LEDs are in the middle beneath the charging port one in "top" of the other (i.e., one is closer to the charging port than the other). Is it correct to say that your numbers are now upside down and the activation button is now closer to your wrist assuming that you are wearing it on your left arm? Typically I find that the the Charge HR reports a pulse which is "low" by 25-30 bpm compared with two chest strap monitors (Polar and TomTom) and another optical sensor (TomTom).

[RobertoME]

Hi there @StephenB427, good to see you around and I'm sorry for the intrusion, hope you dont mind. But I've seen this case with other users. I believe @tractorlegs refers to use the tracker facing inswards. There are a few suggestions to support this way to use the tracker as you can see here: 
Support for wearing fitbit on the inside of your wrist.

Something that works for me when I'm running and I noticed my heart rate is not accurate is to clean any excess of sweat in my wrist and experimenting with how high I place the tracker on my wrist. When you're not exercising, wearing the tracker just above the wrist bone--as you would a watch--typically works fine. However, moving the tracker up a couple inches can be helpful during high-intensity exercises.

I guess with the chest strap, are different technologies that may present variations on the data recorded in comparison to the wristband tracker. Our PurePulse heart rate tracking is the only heart rate technology to offer automatic, continuous wrist based tracking for all-day health insights and workout intensity. PurePulse allows to track workout intensity and calorie burn.

See you around and until the next one.

[StephenB427]

Many thanks for the clarification and suggestions. I'll give them a try. btw, the link to Quora discussions (Support for wearing fitbit on the inside of your wrist) seems to be broken/lost. Cheers, Stephen

[StephenB427]

This morning while using a Concept II rowing machine I tried wearing the Charge HR on the inside of my wrist with some space above the wrist bone. Alas, sometimes the Fitbit was consistent with a chest band recording while at other times it was about 30bpm below the chest band. The bottom line: wrist positioning made no difference in terms of accuracy/consistency. Regards, Stephen

[RobertoME]

Hello @StephenB427, thank you for keep me posted and thank you for letting me know about the broken link. I will try to notify the user, so this can be corrected. 

Now back to your post, I wonder if your try to use your tracker above your wristbone, but facing your tracker normally? I went to test my tracker wearing it inside of my wrist and it happened the same. I think this is due to how the Heart Rate sensor works. Since when your heart beats, your capillaries expand and contract based on blood volume change. This blood changes ares more easy to pick up when you wear your tracker facing outside your wrist, as the surface of your skin is more flat.

For those activities that are not step based or at least not entirely require steps, I suggest to use the exercise mode on your tracker, which consist in holding the side button for a few seconds until the stopwatch appeared. When you finished, do the same process and once it has synced, a Workout activity will appear on your exercise history. This will improve your caloric burn when you do exercises on a rowing machine, or other exercise that is not like a regular walk or run.

See you until the next one and reach me out if you have more questions.

[StephenB427]

Thanks, RobertoFitbit, for another helpful message. I very much appreciate your time and effort in getting me an accurate HR reading. I've been using the exercise mode on my Charge HR for probably 95% of the time I've been exercising and the inconsistency has mostly been there. As mentioned there are occasions during the exercise session when the Charge HR readings are the same as a (adidas, Polar, or TomTom) chest band but often they are different (for example, the chest band gives me a 115bpm reading while the Charge HR shows 93bpm). My exercise plateau of 115bpm is consistent with a recent hospital stress test. Right now my Charge HR shows a resting pulse of 60bpm which is entirely consistent with another HR monitor. At rest the Charge HR readings are consistent with readings in my family doctor's office. It seems the inconsistent/inaccurate Charge HR readings only happen during exercise, which many would consider to be the most important time for HR monitoring. I'd be plesed to try any other suggestions... and one curious question: does the new fitbit charge 2 have the same technology as the fitbit Charge HR? In other words, will the Charge HR be getting a firmware update?

Cheers, Stephen

[Aimeefit]

Hi there! Can someone help me please? I have the charge HR and am having major problems with accuracy readings during HIIT which is really disappointing and not helpful at all :(.  When people suggest wearing it on the inside of the wrist, does that mean underneath the wrist? I'm really confused lol - sorry! Please help! Thankyou 🙂 

[StephenB427]

Yes, I think that is what they mean. However, for me, I found wearing a HR watch on the other wrist is more accurate. I found that making certain it was tight to my wrist was also helpful. My family MD and some online comments suggest that our different (left/right) wrists can have a different placement (closer or further from the skin) of whatever (veins/arteries) provides the pulse for reading by the device.

[Aimeefit]

Thankyou so much for getting back to me! And so quickly too! Il try the other wrist next time 🙂 

[Palgers247]

Hi I got a letsfit band, it had good reviews & it was affordable for my needs, I've tried it both on top and underneath my wrist, at times it's got a mind off its own, it will go up to 90bpm, after a while it will go slowly back down to 59bpm, then will creep back into the 90 range then uptown a max of 141, then it slowly back down to the 60 range, it goes like this through the 45minute hiit workout.

[LindaWindsor]

Congratulations on solving the problem, and dropping your weight.  Fitbit has been very helpful in prodding me into dropping a significant amount as well.

[mere989]

I have the same problems when I do HIIT workouts. Sometimes I get lucky and it keeps up but most of the time it cant keep up with my heart rate changes and reads something like 30 bpm lower. I finished a burpees set the other day and it was reading 128, there's no way that was right. I've been battling with wrist position, inside/outside wrist, clearing off sweat, etc for about a year now and come to the conclusion that it's a luck of the draw. A little unfortunate considering the heart rate monitor is why I bought the device, but I like the other functions enough to keep it around

[Mhasko]

So I have the Charge 2 which regularly reads an elevated HR of 144 or 156 today it was 132 .  I was walking an easy pace, manually checked HR at my wrist 21 beats/15 seconds= 84.  Yesterday the Charge 2 read 144, manual HR was 84.  I wear it on the outside of my right wrist.  Should I wear it on the inside of my wrist?  Do I need to restart it?

Moderator Edit: Format

[crocwrestler]

I have bought an ionic for my partner. She loves it. However when we exercise i seem to burn many more calories than her. She has a pace maker. Im not exactly how the ionic works it all out however im sure it has something to do with HR. She has a pacemaker that is set at max 160. Does she need to change the settings at all on the heart rate zone?

[SunsetRunner]

I use a Fitbit blaze and I’ve used the charge HR, sorry guys , I’ve tried every thing in these pages to get my hr on track, even shaving the hair off my wrist... bottom line, from my experience, my  fit bits don’t do a good job at high intensities, having to try too many options to get the results has made it pointless to rely on these items, I give up... I reach 170bm as verified by my polar Heart rate monitor and it’s also verified with the gym machine and then my Fitbit reads only around 130 and sometimes up to 150; Poor results to say the least, the fit bit blaze works very well for me when I’m  doing low intensity exercises with very little arm/ hand movements and hardly any perspiration.  

[earthwitch]

I have always worn my charge with lights on inside wrist. Never goes higher than 116. And should show 150.

[gregrgay]

None of the solutions suggested here made any difference in the HR on my Charge 2 when outdoor cycling. I did discover by accident, after a morning workout forgetting to end the session, then cycled to work with workout mode turned on. Much more accurate HR in workout mode over cycle.

Seems pretty obvious to me that the issue is a software problem.