Interval training 400m x 5

Today, time is tight since I have a tele-conference at 10:30pm. Therefore, I shorten the interval training to 400m x 6, 1:30 rest in between. But I up the target pace to 4:30. Never try to run at that speed for interval training.


The pace for the 6 intervals are - 4:11, 4:16, 4:15, 4:27, 4:55, 4:53
Obviously, the 4:30 pace is still too fast for me. Not able to keep the pace in the last 2 intervals. The resting period is also a bit too short as my HR have not come down sufficiently yet. Next time, maybe I should have 2 min rest in between and try it again. Hope that I can have the HR goes down to below 130 before the next interval starts.