ONRHYTHM 110 watch and HRM strap black



Made for athletes who want to measure their heart rate to manage their effort
Manage your effort easily with the target zone function.

stock in stores

  • StoreQuantity

view all stores

Ease of useUser-friendly menus and easy browsing
WaterproofWatch: 5 ATM (swimming) - Chest strap: 1 ATM (water splashes).
VolumeSetting of a target zone in heartbeats per minute (BPM)
VersatilityStopwatch, heart rate in BPM, time, date, alarm and backlight
Warranty2 Years
Technical Information

Measurement set-up
Stopwatch, heart rate in beat per minute (BPM)
Watch: CR2032 included - Belt: CR2032 included
Pack content
ONrhythm 110 HRM watch + non coded cardio belt, plastic + user guide
Heart rate monitor
Non coded signal:Plastic belt
Target zones
You can set up a target zone for a better management of your training. It shows you, in real time, whether you are within the target zone you have set up. The ONrhythm 110 features a mode that lets you set up heart rate target zones in beats per minute (BPM).
Time, date, alarm and backlight
Information / Concept / Technology
Elasticised band : 35.0% Rubber - Thermoplastic Rubber (TPR), 30.0% Elastane, 30.0% Acrylonitrile butadiene styrene (ABS), 5.0% Printed Circuit Board Structure : 45.0% Rubber - Thermoplastic Rubber (TPR), 40.0% Acrylonitrile butadiene styrene (ABS), 10.0% Stainless steel, 5.0% Printed Circuit Board Lens : 100.0% Polymethyl Methacrylate (PMMA)


Sort by:
good monitor but for slack quality control
Used for More than 2 years
It is a good HRM for the price , good after sales service provided by Decathilon. Have been using close to 2 yrs ,I guess the transmitter in the chest strap has poor water protection,the back cover does not
close properly .The stop watch function is not clear ,after starting it
can not be stopped with any obvious combination of buttons.
For a senior citizen (70+) it is an useful aide to track level of exercise.
Ease of use and alarms -bpm out of range.
poor documentation and possibly lax supervsion.
Dreadful instructions
Used for 1 week or less
The instructions state that one must follow the intuitive onscreen guide. Complete rubbish !
The instructions cannot be followed.
There are not even instructions on this company site
Thankfully its cheap enough to throw away which is what I will do and I suggest others do not buy it until proper instructions for use are available on this site.
Nothing as it does not work
Instructions impossible to follow
Response of the brand
Hi Tim, 

I'm sorry that the instructions for setting up the OnRhythm110 Heart Rate Monitor are not clear. 

Here are the instructions and some videos:


If you are still having trouble I can ask one of our product trainers to get in touch and talk you through the set up and use. 

Please don't throw away - as the product is covered by our 365 day "satisfied or satisfied" guarantee then you are welcome to return your HRM for a full refund. 

Kind regards, 

David Daker Commercial Director DECATHLON
Used for More than 1 year
very cheap
not much
Good enough for only twenty quid
Used for 1 week or less
Took quite a while and much cursing of Decathlon to get it to read my pulse - but then it all clicked in place when I saw the rain drop symbol on the back of the chest pad - make sure the strap is wetted each side of the main pad, just as the diagram on the back shows. Think this should be made much clearer in the instructions as this seems to be the main problem when trying to get a reading
not too difficult to use
Slightly fiddly at first to get used to
Used for 1 week or less
I tried for half hour to measure my heart rate and it was displayed only one time. I run on a running machine and my heart rate was going high enough but still not picked up.
has good display
heart rate not picked up. difficult instructions,
Response of the brand
Hi Dan,

I have checked with the product manager and he has made me aware that when using the OnRhythm110 Heart Rate Monitor it can be effected by other products giving off electromagnetic waves.    This could include mobile phones or possibly on the running machine if that was also transmitting information.

If for any reason it does not work in a more isolated environment you are more than welcome to return the product to a Decathlon store.    If you often run on treadmills a coded HRM could help as these are less likely to be have interference from other sources.

Kind regards,

David Daker Commercial Director DECATHLON
ONrhythm 110 HRM
Verified purchase What is a review "Verified purchase" ?

Where review is marked as "Verified purchase" confirmed by Decathlon, this means that we could verify that the client who filed this opinion has purchased the product from us.

We can confirm purchases for the reviews expressed on a request by e-mail after purchase or when the customer has this review from his personal space.

If review is not marked as "Verified purchase", this does not mean that the author's review has no experience with the product may have given his review directly on the site without unique identification, or the product has been offered or paid.

The label "Verified purchase" lets help you judge the reliability of a review.
Used for 2 to 8 weeks
Clear screen, easy to use, nice big buttons with good tactile feedback. Picks up my heart rate straight away every time, and the chest strap part still works fine after an accidental trip round the washing machine - impressive.
No GPS, pace counter etc but you wouldn't expect that for the price. Only downside - possibly wish I'd spent a bit more to get one that stores laptimes.
Cheap and functional, great watch for the price.
Could not detect Heart Rate
Used for 1 week or less
After over 30 attempts only detected my heart 3 times. Instructions how to set time and date not as straight forward as they could be. I took mine back and changed it for the GEONAUTE ONrhythm 410 Progress HRM. Problems with that also.
Could not detect Heart Rate
Response of the brand

Thanks for giving us your feedback regarding the Onrhythm 110 Heart Rate Monitor.

I'm sorry to hear that you had issues with our product and I apologies for the inconvenience caused. 

For your information, when your heart rate is not detected properly you can moisten the belt and this should improve the connectivity in between the watch and the sensor. 

Regarding the Onrhythm 410 I invite you to go on the link below where you will find videos with complementary instructions to set the HRM and adjust your personal settings:


If you are still unhappy with the product you still can get it exchanged or refunded at your closest Decathlon branch.

I stay available if you have any further questions .

Have a nice day,

Kind Regards

Cyrille Simon UK Market Manager DECATHLON
All that you need
I wasn't really sure I needed a heart rate monitor, so I found this model's predecessor, the 100, on clearance, so I took a chance. And am glad I did!
It is great to be able to tailor exercise to one's heart rate - keeping within the body fat burning band for example - and to see how quickly one recovers from intense exercise.
The booklet will help you work out your maximum heart rate (easy) and your body fat burning band (not so easy).
I don't see why you would need anything more complex - b
Ease of use, simplicity, instruction booklet.
Quiet beep sound.
  • 1

Other Decathlon Customers have bought