SkiErg Conditioning Workout

3 rounds, each round for time, of:
21cal Ski
Rest 30 secs
15cal Ski
Rest 30 secs
9cal Ski
—— Rest 1 min ——
15cal Ski
Rest 30 secs
12cal Ski
Rest 30 secs
9cal Ski
—— Rest 1 min ——
12cal Ski
Rest 30 secs
9cal Ski
Rest 30 secs
6cal Ski
- Rest 3 mins btw rounds