Awwww hell yeah! Hill sprints are deadly -- good work. You managed to fight gravity and exhaustion at the same time. 400m in 90s is pretty gnarly. When I'm training for races (I'm not the greatest runner by any means), I'm pretty fired up if I manage to get in shape for a 4:50min/km pace. 400m in 90s is 3:45min/km. That's quick, bud! Keep it up!
SO deadly!
It is weird though, it's so steep that unless you're really pushing your sprint, it feels like you're running on the spot and not exerting any energy. I have to drive my arms really hard just to gain any distance.
I mean, there's a big difference between 400m and running a couple of kms. I have no endurance or conditioning at the moment, so a 5km seems so far to me now... but my partner can punch those out a couple of times a week. Still, I will get the 90!