Goal was to run a continuous threshold instead of intervals for mental toughness. My prescribed workout was 6400 at my 3k pace / mile + 35 seconds which was about 5:00 for me through 1600. Solo, I ran through 1600 feeling like a jog, 3200 feeling comfortable, 4800 feeling comfortable still, but got slightly lightheaded at ~5400 and stopped at 6000 instead of 6400. I hadn't hydrated that well today but I still didn't expect that.
Will going 400m short have a huge negative effect on my fitness? I feel like I'm stressing over a minute point but it's still on my mind