The thread Swimming with No Kick on the TI Discussion Forum discusses the various considerations and effects of swimming the crawl without kicking.
Swimmers all over the world do “pulling sets” on which they wear a buoy. This is different from “practicing freestyle without a kick.”
The purpose of the former is to Work Your Arms. The purpose of the latter is to Improve Balance by Activating Spinal Stabilizer muscles.
This distinction between two forms of practice that, on the surface, appear similar is typical of how TI Swimming is different from traditional swimming.
I often practice swimming with a minimized kick. To do this I push off with my legs held in streamline. I then try to keep them streamlined while stroking.
To push off with streamlined legs, I need a better sense of balance to smoothly transition from underwater to surface-stroking. The focus this requires helps my balance the rest of the pool length and allows me to minimize leg action. I check on this by noting how far apart are the toes on one foot from the toes on the other.
I can feel quite clearly that, in order to do this, I have to keep good tone in my deep abdominals. It’s good practice. And entirely different from a pulling set.
How far can a good swimmer go without kicking? 50 meters?
It depends on what you mean by not kicking. We teach non-overt kicking, a relaxed leg action that follows the body’s rhythmic weight shifts. The legs still move up and down, but it’s virtually effortless and much more streamlined. Swimming sans kick (with streamlined legs) as described in the post is a drill intended to be done briefly.