Row Conditioning 
4x 5:00 intervals, broken as follows
1:00 active recovery
1:00 @ r22 75%
1:00 @ r26 90%
1:00 @ r22 75%
1:00 @ r26 90%

Warmed up with DH 10-minute build and then followed along with this DH workout from YouTube. You'll row for 20 minutes continuously, but each minute you'll shift your focus as described above. Held the r22 around 2:17-2:18 and the r26 at 2:06-2:07.