tempo and speed endurance

Had a miserable 4x400m tempo workout at KCD School today, one of my worst.  Cool and cloudy, good weather for a workout, about 50º.    I was fine until it hit me at the 200m mark of 400 #3.   It was all downhill from there.  After a hard slow 4x4, I rested and ran 2 400s at faster pace.

400m warmup, stretches, drills 

Saucony spikes on 

4 x 400m w/ 2 min rest - 69, 68, 75, 85 

rest 

400m warmup, stretches, drills 

Saucony spikes on 

2 x 400m - 60, 62

Felt the hip issue on the last 400 so I cut it short.   Wanted to do more speed.  Will now take 2 days off.  Next workout probably Xmas day in NY.   I think I need both more speed work and more quantity foundation work.   Don't seem to be improving.