Disclaimer : I have limb deformities, but my deformities haven’t been an issue with any wrist based gadget in the past. Especially in the non-dominant hand, apart from it being stunted I haven’t faced restrictions to daily activities due to my disabilities. But I’m open to the idea that the the issues I faced with Fitbit could be related to my medical conditions but the symptoms have been synonymous with experiences of others reported in forums. The content I have posted here is my personal experience with the device & may not necessarily applicable to others. So I would advise you to read through the content and make an informed decision.

So I got the Fitbit Charge HR the other day and wore it to sleep to monitor sleep, the next day I found some numbness and I assumed that I might have wore it tight and confirmed from the manual that I wore it just as advised which is at least a gap of finger before and beneath the tracker.

Fitbit Charge HR

Wearing Fitbit Charge HR, just as advised.

So I continued wearing it through the workout, office and by evening, there were clear uneasiness; tingling and a while later it escalated to pain. Generally main thresholds are way better than average, so I would rate the pain — A pretty painful experience.

So I started conducting some research online to check whether it is an isolated incident and I was able to find dozen’s of complaints & similar incidents reported in even Fitibit’s official forums. [Good of Fitbit for keeping it there]

https://community.fitbit.com/t5/Flex/Flex-causing-numbness-in-arm-and-hand/td-p/183599

http://appadvice.com/appnn/2015/02/fitbit-wearable-device-owners-are-once-again-complaining-about-skin-irritations [See comments]

https://community.fitbit.com/t5/Charge/Wrist-pain/td-p/584090

https://community.fitbit.com/t5/Share-Your-Story/Tendon-pain-in-wrist-and-arm/td-p/884678

https://www.reddit.com/r/fitbit/comments/3yx7q6/charge_hr_wrist_painkeep_it/?utm_source=share&utm_medium=web2x

https://www.reddit.com/r/fitbit/comments/3nb0c3/charge_hr_creating_wrist_pain_anyone_else/?utm_source=share&utm_medium=web2x

https://community.fitbit.com/t5/Charge-HR/Charge-HR-minimizing-EMF-EMR-radiation/td-p/977073

https://community.fitbit.com/t5/Charge-HR/Wrist-pain-with-fitbit-Charge-HR/td-p/920034

Owners complain about deep tissue pain from fitness device Fitbit

Fitbit is swamped by complaints that the device is leaving red marks The Fitbit Charge HR valued at around $200 measures a person's fitness One Sydney customer said the company refused to refund the product Fitbit reportedly sent her a written letter asking her to first destroy it A customer from Adelaide also requested the company recall the product Fitness company Fitbit has received an onslaught of customer complaints from users who found themselves with 'uncomfortable deep tissue pain' after wearing the device on their wrists.

Plausible reasons being stated w.r.t numbness, tingle, pain :

1. Wearing it too tight, might press the median nerve resulting in _Carpal Tunnel Syndrome — _http://www.ninds.nih.gov/disorders/carpal_tunnel/detail_carpal_tunnel.htm.

2. Electromagnetic hypersensitivity — “variety of non-specific symptoms, which afflicted individuals attribute to exposure to electromagnetic fields”. According to the World Health Organization, “EHS is characterized by a variety of non-specific symptoms that differ from individual to individual. EHS has no clear diagnostic criteria and there is no scientific basis to link EHS symptoms to EMF exposure.

Fitbit Pure Pulse ® to measure heart rate.

3.**_ Pre-existing medical condition_**— Fitbit states a ‘Special notice’ in it’s attached handbook -

Fitbit Charge HR special notice regarding pure pulse technology.

In my case :

1. I’m quite sure that I wore it as advised i.e not too tight nor loose. I have been wearing watches in the non-dominant hand for decades and android wear based smart watches with health trackers right since they were available.

2. Electromagnetic sensitivity isn’t scientifically proven and I have been living with gadgets and surrounded by wireless devices for better part of my life till date and I haven’t faced any issues . I haven’t wore a LED based heart rate monitor in my wrist before and so I cannot conclude totally on whether I haven’t been affected my electromagnetic sensitivity. I can try another wrist based HR monitor to ascertain but I’m not willing to do so without guarantee from a physician that the experiment wouldn’t result in any long term health defects.

3. Pre-existing medical condition — I have undergone ilizarov ring fixation on my legs for correction of deformities at my early age resulting in stunted growth. I’m leading a normal lifestyle and none of daily activities have been impaired by my medical condition. Still, I’m open to the idea that my experience with Charge HR could be related to my medical condition but the symptoms I’ve experienced have been in synonymous with some others with no previous medical conditions.

My communication with Fitbit :

Conclusion :

I have since returned the fitbit Charge HR as advised and after a week my hand starts to feel better. Still, I do feel my wrist hurt when I touch the spot where the tracker was placed. I hope it gets better in a week; else I would consult a physician.

fitbit is a great company, they’ve made healthy lifestyle a fun activity to pursue for many. I was eager to try their product and since I was wearing other wearables regularly and was confident of fitibit’s heart rate monitor mechanism I didn’t do much of an research before hand on whether it would have any side effects on me. Still there are plenty of happy customers of fitbit Charge HR and so are customers who complain of similar experiences as me.

I will be glad if fitbit’s engineering team is able to conclude the reason behind this ‘rare symptom’ as put by it’s expert and till then let it’s customers know on plausible risk in wearing the device for some users in a better way in it’s website and in it’s e-commerce parter sites.

If Fitbit would like to collect any data from me for its analysis using Fitbit Charge HR, I would be happy to help them, provided I get assured that there will be no long term health defects in doing so by a physician. For the sake of science!

Update : 27-Dec-2017

You can see that I didn’t wear Alta HR tight.

I wore a Fitbit Alta HR for a week to check whether my experience still holds, within few minutes the numbness, pain started to surface. I had the heart rate monitor ON for a day and when it became uncomfortable the next day, I switched off the HR via Fitbit app.

Not sure whether I had the option to switch off HR last year.

Not to my surprise; the numbness, pain, tingling sensation ended immediately. I have seen in forums that people who have switched off HR or covered it with some material have witnessed similar results. I wore the fitbit for a week without HR to ensure this results and then switched ON HR for a while to test the results again. HR causes me pain.

I’m now confident that I belong to select few people who have issues with heart rate monitor on their wrists. I don’t think it’s limited to just Fitbit devices, it’s likely I might have issues with other wearable with HR sensor but I cannot say for sure unless I try them. I would definitely update this post when I do so.

What’s intriguing is, there’s enough users reporting it to be considered for a thorough investigation on HR sensor’s effects on people; yet I don’t see anything other than loads of forum complaints and occasional blogs, vlogs like this.

Update (2017) : Since it’s been over a year I published this, I wanted to check if there’s any change w.r.t Fitbit on my hands. So in the name of science, I tried an Alta HR and I’ve updated this story.

Update (Sep 2018) : I’ve been diagnosed with spinal stenosis. I wondered whether the tingling sensation from Fitbit was correlated with it, so I tried it on after the surgery; but there wasn’t any change with my experience — tingling & pain on the hand where I wore Fitbit.

Update (February 2019) : I tried Apple Watch Series 4's heart rate monitor and I faced tingling sensation in about 30-40 minutes during the initial attempt. I didn't own the device, so I couldn't do a prolonged test to state conclusive results.