I have run 51.83 in the 400. My best 800 so far was a 2:04 but I went out in 54 and came thru the 600 in 1:26 then died the last 100 meters. Yesterday I did 3x400+200 jog 100 meters in between 400 and 200 walked 400 after each set ran 55, 29 , 58,29, 60,28 . What should I be shooting for in my next race.