The wiki suggests that a minecart track for swim training only be 5 deep, but it does not explain why. I am hoping someone can clarify while my dwarves work on the science apparatus I have designed for testing this idea.
As the title suggests however, I am not just trying to train swimming, but attributes. Just for fun, I am maxing out some dwarves in various ways (legendary +5 in a wide range of skills, and as is important here, highest tier in any attributes I can figure out how to increase). And this sentence on the adventure mode part of the swimmer wiki page caught my attention:
Drowning itself can also be beneficial, as certain attributes, notably toughness and endurance, greatly benefit from the strain caused by the experience
I then found this forum post:
http://www.bay12forums.com/smf/index.php?topic=140163.msg8006324#msg8006324I recommend jamming them into two tiles with 13/7 water - the half-time drowning will give about 550 points/month to toughness and endurance (doing three tiles with 776 will not boost this). Civ alerts are excellent for doing this for whole population.
This implies to me that I should be able to come up with a length of track using rollers, which if submerged 7/7 under a ceiling, but in air on both ends, will train swimming, toughness, and endurance while not risking death to the riders.
The apparatus I have designed will let me figure out how many rollers at what power are needed to keep the cart moving and push it up a ramp out of the water at the end. But I cannot find any data as to how long a very low stat dwarf can be drowning without dying. In the worst case scenario I should be able to come up with a safe length through save scumming, but I am hoping someone with a better understanding can save me some time on my research.
edit: I had forgotten how rollers work, should have done more research on that front before starting the design. Only real question is therefore how many submerged lowest power roller tracks can a dwarf ride before dying from drowning.