Say I'm doing 10x1k at 10k pace. Do I want to try to run exactly 10k pace the whole way or would it be better to start the first couple intervals slower and do the last couple faster than 10k pace? Should I start intervals slower than the goal pace for those 2.5 laps and sort of kick a little to hit my goal times or run them pretty even? I've always just run them as close to goal pace as possible before with the last 1 or 2 faster.