Really good spin class again last night. This one was almost entirely slow to moderate cadence riding, but with moderate to high resistance and long (7-10 minute) endurance intervals. I don't know what my total ride time or calories were...something like 50 minutes and 720 calories, but my avg HR was 77% of max and max was 93% of max. Even though we weren't ever pedalling really fast, it was a tough workout...