- fast motions tend to contract inward toward the center.
- slow motions tend to extend outward from the center
I have found that trying to move quickly in a conflict tends to shorten the encounter space and artificially reduce ma-ai. In my practice I see this most in the backwards turning steps (a.k.a. 'goblet steps') of Tegatana no kata and in the first step of shomenate. If I do these motions at a slow-to-moderate speed and relax then I am able to maintain a relaxed natural posture and a normal ma-ai. But if I do them quickly I seem to be jumping back almost into a wrestler's stance, ready to engage - and I tend to be a couple of inches closer than I wanted to be.
Play with this some and see doesn't moving a little more slowly help you maintain a more natural, upright, relaxed posture (shizentai) while opening up the space between tori and uke.