This is 3x25m flys on a deload week and the times were all in the 2.72-.76 range which is kinda fried ngl. All my fly times have been stuck at like 1.02-1.08 per 10m for a few months and idk how to change that atp any tips (I don’t have any access to overspeed except for downhill runs I suppose )

I continually have lower hamstring issues on my right leg and whenever I take time off and come back the injury seems to pop back up after just a few top end speed sessions and idk what to do. Anything form wise that could be causing my problems that I could fix?