There’s no floating involved in a MaxV fly run, that’s why they are so short.As otherss have said, maxV is the maximum speed you can run.
My team try to hit maximum just before they hit the zone and then run absolutley flat out through the zone.
Some take longer to build up than others. My long sprinters like a longer build-up. As star says, the short sprinters will build over 30-40m from a standing start, building up using maxV mechanics, rather than a pure acceleration phase.
If I remember from another thread, you’re still quite young, so 10 or 20m flys are probably enough. Quality of the fly is better than trying to extend it and losing form or speed.