OHR and responsiveness

I recently lost my Scosche heart rate monitor and instead of replacing it I have been trying to use the monitor in the watch. It seems to work well enough when I'm sitting around but on a treadmill not so much. I have been trying to keep my heart rate at a particular rate for base building by varying my pace, but I'm finding that the reported rare jumps around quite a bit. If I put my hands on the treadmills heart rate sensors sometimes they match but they are often different by 15bpm. I know the treadmill can be off too. But the real issue is that the F5+ number will seem to sometimes jump around from say 128 to 135, or get stuck at a number like 135 when I can feel that it should be much lower.

Has anyone else seen this? Any tricks to make it work better? I wear it tightly on my wrist just above that bone that sticks out. My wrists are not big, which may be the problem.

0 hansap over 6 years ago

Do yourself a favor, buy a new Scosche Rhythm24. OHR isn't the same.

0 HeliosJim over 6 years ago

Is the Rhythm 24 worth the extra $20 over the Rhythm+?

0 Dr Phil over 6 years ago

Has anyone else seen this? Any tricks to make it work better?

There are many posts related to this for all of the devices using WHR (OHR). Have a read through some of them - you'll even find some specifically for the 5+ probably. Read this too - https://www.wareable.com/sport/optical-heart-rate-tech-the-experts-speak-9763

Long story short, whatever you do, it works for some, but not good enough for most. It's an inherent limitation of the technology.

"And while runners may one day be able to use optical tech for training sessions, when lag times and algorithms improve, for gym bunnies and HIIT fans it looks unlikely that the wrist will ever be a serious option"

0 SAHO over 6 years ago

Thanks for that link philipshambrook - very interesting read which basically explains and sums up my own experiences with various trackers and watches over the last few years.

After hanging around in here for for some time and seeing this topic being brought up again and again and again and again, I think the link to this article should have been made a sticky thread at the top of the forums for each and every model that contains an OHR! ...but I guess a certain marketing department would get that removed rather quickly.

BTW: Has anyone made or seen any experiences with the HR sensor on the new Polar Vantage series? Looks like they're trying to step up their game by including some kind of electrodes (skin contact measurements?) together with their optical sensor, as well as having both red and green LEDs. Might not be correct, but is there actually 4 light sensors as well?

0 HeliosJim over 6 years ago

That article does not necessarily condemn optical heart rate sensing, it mostly condemns it when used on the wrist, and even then only with high intensity activity:

"When you go to other activities, it's a whole different ball game. During cross fit or weight lifting, the head is a great location, good blood flow, stable and a good fit, as is the upper arm. The wrist can completely out. If you're doing pull-ups or arm curls, they may not be measuring at all.

And I have had good luck wearing an optical HRM on my upper forearm. I may go back to that, but I'm trying to decide if I'm better off with something that works in the ears or a chest strap. Since the chest strap is known to be good I'm leaning that way, but it's not very convenient and needs some sweating before it works. Decisions decisions...

0 HeliosJim over 6 years ago

As I read further, it seems the RHYTHM24 does not transmit accurate HRV data unless you're still, and not running. Also it seems the Fenix watches use HRV data for VO2 Max estimation, recovery time and lactate threshold calculation. And, it seems the Garmin HRM4 Run does transmit accurate HRV data while running. So, if all this is true than the HRM4 seems to be the better choice. Is all this true?

0 Dr Phil over 6 years ago

needs some sweating before it works

Soak it in water before you put it on. Or you can use electrode gel too.

0 SAHO over 6 years ago

I've never had any issues with conductivity with any of the chest straps I've had. Wet/dry, hot/cold, always get a reading immediately. Maybe my skin is a special kind of conductive - who knows, anyways I don't think there are any conductivity issues that can't be solved with two drops of tap water.

I simply don't get why people (not pointing at anyone in particular) "hate" the chest strap so much when exercising. To me it's a no brainer; Put it on and you have a rock solid accurate HR reading without any precautions required whatsoever. Either you get a signal or you don't, and I would argue not getting a signal is very very rare.
With todays straps I don't buy into the comfort argument either - if you wear the strap so tight that it's uncomfortable, it's too tight.

And last but no least: A simple chest strap is super cheap in terms of bang for the buck compared to other options.

0 Baz 8755 over 6 years ago

I agree with the above, I never have problems with chest straps. Just put a good amount of spit on the sensors before putting on and both my premium and basic strap work first time every time, and have done for around 10 years.

As for comfort, again I do not find it an issue and don't notice it's there. Although I have a friend who has never worn one and when he borrowed mine he did say he found it too constrictive, I guess it's just a personal thing.

0 SAHO over 6 years ago

Soak it in water before you put it on. Or you can use electrode gel too.

I believe this is a misunderstanding.

If anything, it's your skin that needs to be wet (/conductive) and only the small areas where the electrodes sits. From what I can see the electrodes are covered with some kind of material that doesn't absorb moisture anyways. Electrogel on the electrodes I can agree with, but soaking the strap (fabric) in water won't change anything.