Any special strategies to address autoimmune visceral adiposity?

I was laid up for several months after a near-fatal crash a few years ago. The inactivity of rehab caused me to pick up about 25 lbs, but not in the form of subcutaneous fat that can be shed by traditional means. I am 64, and have been an avid rider all of my life.

The most effective means I have found is to aggressively attack hills and plateaus during the hottest part of a summer day. This works well -- once I lost about 30 pounds this way -- but I cannot keep that up once the season changes. Besides, these rides can take up to three hours. (Walking offseason is out of the question -- don't ask!)

Many thanks for any insights, especially from medical people.