How to Pace Yourself in Structured Work

I'm not going to call it necessarily a burning because it's almost because I don't get to the point where my legs are burning it's where I'm attempting to put in an effort. It's kind of just pace learned over you know 23 years of training so really just it's facing it on that feel in my body which I'm not really describing that well but I know it well enough based on this is more of a fatigue I feel in my legs and actually as far as increased respiration right over the course of the segment.