Originally Posted by cotaguro
After doing some tough climbs (5 miles, 11% grade), I experienced lower middle back pain (I've had some occasional pain before).
Since your butt muscles pull on the lower back... one remedy to this is to work on your core strength to balance the forces on your spine. It's not uncommon to have back problems after hard climbs if the spine is getting tugged on without enough resistance.
I'd think 5 miles of 11% would leave many of in a bit of discomfort...