Today I did 3x500m with 200m jog recovery.. they felt relaxed but the entire purpose of the workout was turnover. Especially the last 200m. I didn't time the last 200m but they were quick. They were 1:28,1:31, & 1:23 workout started at 4:34 pace then dropped to 4:54 & whole workout was 4:24.. what can i possibly run in the 16 and what are ideal splits to achieve sub 5