40 min steady state

5,4,3,2,1 @ 18, 20, 22, 24, 26 (@ +14, +12, +10, +8, +6)
X 2

4,3,2,1 @ 20, 24, 26, 28 (+12, +10, +8, +6)

Building endurance at a low rate with low to medium intensity.