Let's say I have a spaceship under construction with a habitation module and I want a reasonably compact means of mimicking the compressive effects of gravity on the body I have two candidate ideas for achieving this both of which boil down to creating a significant downwards acceleration for astronauts inside the module over and over again at a high frequency and with significant G force to make up for more constant force not being feasible and with with the rational that acceleration force will effect the entire body more evenly than simply wearing a magnetic suit and being constantly held down and pushed down by it.

Idea one: The astronauts wear air filled suits and reside in a fluid filled chamber and at a high rate with significant force this fluid is made to suddenly flow down into a drain in the designated floor while replacement fluid comes in from the designated ceiling.

Idea two: The astronauts wear ferromagnetic suits and spring or piston bearing shoes inside the habitation modules and a strong electromagnetic is turned on and off in order to accelerate the crew downwards over and over again dragging them with the ferromagnetic suits and pushing them back up with the springs or inert gas filled pistons.

Would either of these ideas work in theory and if not why and can either be adjusted to be more feasible? Is my reasoning good and what can I do to improve it?

I am trying to design ships for my setting that better justify long term habitation in space without having to be too out there or too large.

I considered trying to channel ultrasonic waves through the bodies of crew members but that seems to not be an option, see: Could a form of acoustic levitation be used as artificial gravity?

Could a vehicle levitate through use of ultrasonic sound waves?

Though I am somewhat skeptical as I was under the impression that ultrasound travels well through most tissues and so could be used to deposit force farther into the body.