In ear earbuds. I blimmin' hate them but my Audio Technica over ears are too bulky for the gym.
Bit off topic, though if anyone could recommend cheap but decent wireless headphones, for the gym, that are not in ear I would appreciate it a lot (I'm in the UK).
Not cheap and i already said it in another comment. I absolutely love my aftershokz open fit. My ear hurt like hell when i use in ears and they never seem to fit. These i wear sometimes 10 hours a day. I went to the shower multiple times because i forgot i was wearing them. They sound really good imo, battery life especially with the charging case is fantastic. It's perfect to cycle or in areas where you still need basic awareness. Like i can talk to people at work while i have some music in my ears.
Do they hurt the backs of your ears? I've had some cheap in-ear headphones that also had curved plastic to fit around the shell of your ear for stability. I'd have to take them off after an hour or two in pain, but not because of the in-ear component.
Not the one you replied to, and I have a slightly different model (OpenRun Pro) but in my experience, not at all.
They work a little differently with bone conduction. This requires a tiny bit of pressure just below your temple in front of your ear. It doesn't hurt, but if I wear it all day long (way more than a couple hours) I find myself a little bit... Annoyed with them? Just a little. I still happily put them on again the next day. Zero pain.
Oh, and bass comes out a little differently and kinda tickles a little bit. If you listen to stuff with a lot of bass frequently it may not be your best option. Sound quality is generally like a pair of Sound Blaster speakers from the 90s: it gets the job done just fine, but it's not for audiophiles.
I also stan aftershokz. For gym use I use ear plugs to block out machine sounds and I can still hear my book/music/video just fine. The battery life is great - I charge them nightly to be certain they won't die, but haven't had any problems running them two days at a time for 8+ hours on the occasion that I forget.
Also a huge fan of mine (OpenRun Pro). Worth mentioning that they're pretty lousy in noisy settings, like airplanes or mowing the lawn, but I love being able to listen to things without separating myself from the outside world
I know you're looking for on or over ear, but for the gym, it might make more sense to get the non TWS earbuds like the LG Tone or similar. They're light in your ear as all the battery weight stays on your neck.