-
@nefarious
Another option is Polar OH1. I don't really like chest straps - feel constricted a bit when running. The arm straps seem to be far more reliable than the wrist ones despite both being optical. I have a Garmin
945935 and I've just disabled the wrist sensor since getting the polar.
Less movement, less affected by sweat, and fleshy of your arm is a better place to record or something.
OH1 also includes a clip to attach to goggles which I haven't used myself but it's an option.
I definitely prefer it for bike and run though.Obligatory DCR link - https://www.dcrainmaker.com/2019/03/polar-oh1-plus-optical-hr-sensor-in-depth-review.html
duncs-
Ooh, had missed the OH1, that looks good (as I'd prefer something that clips on to the goggle strap rather than a chest strap for swimming).
For general running I just use the wrist sensor on my 935, it's mostly ok for running (but really struggles with big swings in HR that happen during 5-a-side). Also don't get running dynamics stuff (not that I care about it that much) with wrist or OH1 - I'd need a running dynamics pod clipped somewhere to do that. If I need to wear the OH1 and a running dynamics pod I may as well just wear my HRM-Tri strap.
Looks like a bit of a faff to get the HR synced with a swim activity if using a Garmin (and not using the Polar stuff) but I'm up for a challenge.
Will add the OH1+ to my "possible" list, although I'd much prefer it to support ANTfs so that my 935 can download the HR from it post-swim, rather than having to faff around with it at a later date. Will hold out in case they add that to a newer/future model.
Greenbank
As TW says, there's the ability to store the data whilst it can't communicate with the watch.
But there are two other major features (one required, one useful).
Being waterproof is definitely a requirement. Not all HRM straps can survive full immersion in water, they'll survive getting sweaty but not immersion.
The other difference is to do with the stickiness of the strap. With the Garmin straps, the HRM-Tri strap can do all of the above but if you wore it in the pool it would slip down your chest each and every time you pushed off from the wall to start a length. The bright blue HRM-Swim strap has a wider strap made of stuff that clings more to the skin, so it stays in the right place when you push off from the side. It's still comfy though, I've worn my HRM-Swim for many a 1h40 swim with no irritation.
If you're doing open-water swimming then a HRM-Tri strap would be fine (except for any initial dive in), if it's worn under something (e.g. a tri-vest or wetsuit) then no problem with that.
Anyway, running. Avulsion fracture of the medial mallelous from playing 5-a-side so I'm off running (and 5-a-side obvs) for a few months whilst the physioterrorist sorts that out - can also get my dodgy hip flexor strengthened too.