Originally Posted by CbadRider

I worked with a coach several years ago when I was trying to improve my marathon time. He stressed quality over quantity when it came to workouts, and it made quite a difference for me (improved my marathon time by 30 minutes in 1 year).

If you're not really getting any benefit from the extra 30 minutes of spinning, other than just increasing your time in the saddle, I'd drop it and get the extra sleep instead.