I just had a similar borkage happen with the swimming state, as a side effect of a problem with the baby controller. Sim was swimming through the ground instead of walking or running, would pop out of the ground to sit in a chari or pick something up, then switch back to swimming when a task was finished. Only way to fix it was to reset the sim twice.
I thought you could also fix that by getting them to climb a pool ladder (make a bump in the ground, place a pool ladder, make them climb it). The trick is to get the 'ambulation' state to reset and that's what the ladder does.
First thing I tried was getting her back in the pool, then climbing out the normal way. It didn't reset it.
Next was trying a few things that interrupted her normal state, thinking those would reset the swim effect. You know: ninja teleport, sitting in a chair and getting up again. No go.
Then, I sent her off-world with Jogging. That had no effect.
I knew from the start that reset should work, but I didn't want to lose any skillpoints or other advancement she had done that session. So, I sent her spouse off to check on his business (he has a dojo where he teaches Tai Chi,) and when he came back, reset her, twice. That worked.
For future reference, don't queue up something like "Use Pool Slide" after a command from the baby controller to fetch the kid. The sim fetches the baby, then takes the baby for a swim, making it impossible for her to exit the pool -- which was how I wound up with a sim that swam through the ground.