Today my coach told me to do 5x400m @85% effort. Well....the track is under snow. And the Olympic Oval is a 25 min drive away. Soooooo....I went to the indoor track at the U instead. It's only 292.6m, so 2km is a bit less than 7 laps. I decided that 7 laps would do the trick.
I did a nice easy warm-up - super slow on the first 2 laps, concentrating. Plus I did lots of glute exercises and massage with the ball before starting on the workout.
I felt pretty good! My piriformis was bothering me a bit on the first warm-up lap, but then it was fine as I got my technique under control. Then again at the end it was a little annoying, but after the workout it felt just fine. I think I had pretty good technique throughout and was concentrating very hard.
And guess what? My speed was decent. I did mostly 1:40 laps, with one 1:42 and the last one 1:38 or so. 1:40 per lap is 5:42/km, which I think is great for 85% effort for now with injury recovery. I'm very pleased. HR was maxxing out at about 160.
Garmin data here.