HR on Charge 3 not accurate DURING TREADMILL EXERCISE APP

[MrMarv]

First off, I am a big supporter of the Fitbit devices and their firmware programmers - not as much of a cheerleader sometimes for their app and web development teams (probably Project Leaders and Quality Insurance or maybe the people that push them to market too soon), but I still respect them.

And for the most part, the Charge 3 has been holding its own in the bpm area - when it says 108 and I count 27 beats in 15 seconds I smile. And it rarely disappoints me.

Until I put it into exercise mode, that is.

And I have held off until the latest firmware update came through last night so I could run another short test.

Last night and tonight I performed two treadmill exercises, 14 and 7 minutes in length at 2.2 and 2.5 mph.

For the first exercise last night, I did my normal 50 squat reps and crunches and by the time I took a short break and hit the treadmill at 2.2 mph my HR was up to 100 and increased to 137 (low to mid peak) by the 5 minute mark. All expected; I'm not a youngster, after all. At 6:10 it was at 100 and ten seconds later, at 63 bpm!!! Huh? It started a little climb but by 8:30 it was at 61 bpm. This is for a 66 year old male with a pacemaker/defibrillator with a resting heart rate of 68 to 72. I ended the exercise after 14 minutes at a recorded 111 bpm.

And the chart of the activity definitely shows those three minutes as being under fat burn zone of over 77 bpm.

This evening I performed no pre-walk exercises, unless you count helping clean up after dinner, and started my session at 86 bpm. At 2:00 into the walk I was down to 74 and at 1:59 I was at 71. Up to 84 at 2:20 and back down to 66 at 2:35. From there on, with me increasing the pace to 2.5 mph at 4:00 and 3.0 man at 6:00, it quickly made its way back to fluctuating between 101 and 114, finishing at 104 bpm at 7:00. 

What the heck? There is no way I'm going to drop lower than 90 bpm in those scenarios. I didn't stop to take my pulse manually during those two abnormalities, but trust me, I will tomorrow.

Moderator edit: updated subject for clarity

Original poster edit - Moderator did not clarify, but rather muddied it up.

[MAC-1206]

I am very disappointed with the Charge3. I bought it specifically for the HR and it doesn't come close to the BPM on the treadmill. I checked it on 2 different days and different machines. The treadmill shows 171 and the C3 is 115. I have tachycardia and prefer not to exceed 155. I don't need to lose weight. I used a sweatband to keep the C3 positioned correctly since my wrists are thin. (Not on top of it, but next to it.) 

[SunsetRunner]

What a piece of crab. The heart rate is off about 50bpm more than my actual heart rate when exercising. And it looses connecting, not showing any heart beat more than half the time I checked it. There are times, often hours I cannot connect to any devices. This is my second one in less than a week because the first one had problems too. But the one I have now is worse than the first. I am trying to put off making a decision whether to exchange it for another or just returning it an buying a more expensive apply watch, although it's much more expensive. No watch is worth any money that can't keep a fairly accurate heart rate because it makes everything else inaccurate. I am very disappointed with YOU fitbit!

[Whersringo]

I've experienced exactly the same thing on the elliptical or stationary bike or treadmill. The Charge 2 reading and the machine would register almost the same heart rate, no matter my heart rate.  But with the Charge 3, when I hit 145-150 bpm and up, the Fitbit will drop 30-40 bpm, and nothing is do will change it (moving the band higher, switching wrists, etc).  Very frustrating. I went back to the Charge 2 in the gym.

[paultallistall]

Used it one day at the gym and knew it was off.  Same issue as other have stated.  Much lower HR reads than the sensors on the gym equipment,.  Returning it ASAP.  Junk.

[SunsetRunner]

Update: I returned the second one and did not try a third. Same problems. When it recorded 

I was in deep sleep while I was watching TV, I realized nothing worked on the watch. I did learn something though, check out the forums defore i buy something. After I returned the watch, I went to Apple to look at their newest version. I managed to keep my self control so I can read up on it. Unless fitbit comes up with a fix really soon, then apple it is.

[madairbob2]

It is strange, people like you and many others reply to my post. All except the people from Fitbit. Still no solution. My Fitbit charge 2 was way more accurate then 3. Nice to hear you still have time to get your money back.

-BobbyL

Sent from my iPhone

[hosehead]

Short answer - problem solved by getting my wrist damp under the fitbit sensor and pulling the strap snug.

Long answer - I had the same problem with my Charge 3 showing lower heart rate during exercise compared to my Polar chest strap (and manual pulse check).  Polar would read ~150+ while Charge 3 is sitting around 125-135.  Polar chest strap recommends wetting the contact point to get better reading so I tried that with the Charge 3.  Took off the Charge 3, rubbed some water on my wrist under where it sits, put it back on, pulled the band snug, and voila, same reading as the Polar.  I don't know why it works, but I've been doing this for about a month now and it works like a charm every time as long as it stays damp and snug.

I wear it on my non-dominant (left) wrist, on the outside of the wrist, over some arm hair.  

[TwinB10]

I’ll try that. Thanks!

Sent from my iPhone

[MAC-1206]

Back in the old days, my husband says that polar recommended using electrolyte gel. I seem to remember spitting on the chest strap. Thank you for the suggestion.

[Rubinstar]

My Fitbit 3 does the same thing! I get a spike in my run where it hits 203, or 206, tonight it was 209! But the average is probably ok and most of the time the rate seems accurate. But worrying but I’m still alive so hoping I’ll stay that way for a while longer 😅

[knittenlady]

Thankyou! Your method worked for my Charge 3, which had been giving me scary low heartrates on the treadmill. Now it’s great!

[knittenlady]

P.S. That was a reply to Hosehead’s post.

[OldBob3301]

I'll try your solution.  I've always had mediocre HR results from Fitbit.  For example; I did a 3 mile walk with a peak elevation climb of 400'.  I wore both the polar chest strap and a charge 3.  The charge 3 is placed snuggly just where fitbit says to put it.  My maximum HR according to polar was 154 with 30 continuous minutes of effort over 148 bpm.  My peak HR according to fitbit was 128.  If you're serious about fitness that's a dangerous difference and if you're relying on the HR monitor you can be overtraining.   The fitbit seems to be OK around the house and going shopping, but I am skeptical for serious fitness.  It's advantage is that it's convenient.  The downside is that you need a chest strap to ensure that your fitbit device is accurate through the range of exercises that you do.  

[Michaeloldathle]

Hi, I have run for 60 years, many sub2'40 marathons, a while ago, total 115,000kms. Charge3 is great, for sleeping, biking, living heart rates - really accurate -  but dreadful for running heart rate, 30 bpm higher than my polar strap and counting carotid beats. I have tried both wrists, tight or not. It seems a bit better after 30 minutes running, but that isnt good enough for an old runner, who is heart rate limited. I think it is picking up movement artefacts as I get similar, albeit spiky, readings when it is in my pocket and I go running! So I use a polar strap for running, and keep my charge 3 on for life graphics, but ignoring it for running. The graphics are better than Polar. This isnt very good though, fitbit!

Michael

[TinaMarie73]

I have been using the Fitbit charge 3 and my resting heart rate goes down to 54 to 58 a lot and lower at sleep.But heart rate goes up with movement. Is this really accurate. I do walk some but I’m not athletic. This just has me sacred cause everyone says resting heart rate is 60 to 100. In love having the Fitbit but it’s scaring me. Mymm

[TinaMarie73]

I have been using the Fitbit charge 3 and my resting heart rate goes down to 54 to 58 a lot and lower at sleep.But heart rate goes up with movement. Is this really accurate. I do walk some but I’m not athletic. This just has me sacred cause everyone says resting heart rate is 60 to 100. In love having the Fitbit but it’s scaring me. Thanks for any advice.

[Michaeloldathle]

My wife who isnt athletic has a resting heart rate of 54. It is very variable. Many people have resting heart rates in the 50s, or even 40s if fit. Eddy Merckx had a resting heart rate of 26, and my kid brother had a heart rate of 28 three days before finishing third in the Olympic marathon - but that is exceptional !

at 69 yo my resting heartrate is still in the low 50s.

Most countries advise seeing a doctor if you havnt previously when contemplating strenouous exercise for the first time for years, but heart rates in the 50s are very common.

[TinaMarie73]

Thanks so much! I’m 46 and weigh over 200 pounds. But am some what active. I just thought below 60 beats more to the 50 might be dangerous. I’ve also heard that maybe the heart rate could maybe not be accurate on these devices. Sometimes we just need a little advice.

[Robin007]

I bet you are fine.
Maybe manually check your HR periodically though day including when you've been resting in bed for at least 10 minutes.
Check wrist/throat with middle finger etc for 15 seconds....multiplied by 4 etc 🙂

Sent from Yahoo Mail on Android

[TinaMarie73]

Thanks Robin 007 I hope so earlier it went down to 50. I read it could be Bradycardia but i don’t understand it very well. It goes up with movement and exercise just gets low at rest and sleep. I’ve heard at sleep it’s supposed to. The internet tells you all kinds of stuff like it’s not normal.