This is a great all-rounder workout. It starts off with an easy warm up followed by 10 minutes at the top of zone 2, straight into 5 x 30 on, 30 off, working through multiple zones. After fully recovering from the first block you get into the main set. The main part of today's workout is 4 x 60 on, 60 off between zone 2 and zone 5. The final block of work is an all familiar 20 seconds on, 40 seconds on x 8.