More cardio suffering via Rouge echo bike: it's like a spin class that also works your arms.
Warmup 5-10 mins moderate pace on bike.
Part1: 20 minutes / 20 rounds of:
40 seconds zone 4 effort (max sustainable cardio, not anaerobic) then 20 seconds rest.
Rest 5 minutes
Part2: 5 rounds of:
:20 seconds absolute maximum sustained sprint all out effort
2:40 rest/slow recovery (you will need it)
5 mins slow speed cool down
Core: 100 sit-ups, 50 leg scissors
Stretch