Would using flying sprints such as flying 60s,80s,100s be good for developing speed endurance? I know relay legs are basically that but im thinking more of using a longer build up zone (25m or so) than a acceleration zone in the relay is.
I tried a few of these the other day, did 3x flying 80s with about a 25m build zone then a flying 120m. They felt great. I found that when I took my time driving into it that it took the tension out of my top speed and I was able to relax much easier instead of pushing hard and carrying that tension through the run.
With that being said, I think these runs carry a high CNS load because I was wiped for the next two days.
60 meter flys, with about a 30m leadin, are fairly commonly used to work on the finish of 100m.