Breakthrough: Warm-up well for 10' and then do 30 x 30 seconds at 90% effort (9 on 1-10 RPE scale) with 30-second spin recoveries. Stop if speed drops by 1 mph (1.5 kph). Rolling starts, standing, big gear. Get to top end quickly. Cool down 5' easily and stretch.
MS: then 12x1' alternating 4% grade, 4.5% grade and 5% grade. Easy 1.5' between each effort. HR should move up to sub LT about 8-12 beats below.
CD: 1 mile cool down