Thursday Intervals

Did the same interval session as the last few thursdays. 1 Warm up circuit, then 5 at pace with 2 min recovery. Times went 6.21, 6.18, 6.25, (wore joggers for 3rd rep) 6.20, 6.16. Another good session. It seems to get quicker each time I do this session. Either im getting quicker, or I was bludging in the past. 16km.