I spend 40 minutes on the Schwinn Aerodyne stationary bike with elliptical arms at the gym. The bike pedals drive a big fan for resistance, and the elliptical arms can drive the fan even faster for total body exercise. It is incredibly aerobic and incredibly boring. I took this selfie in the window.

More power to you. I can't do indoor riding, I find it mind-numbingly boring. Boy child has the fancy computer trainer setup where he can pretend he's riding in the Tour de France or whatever. That works for him, it wouldn't for me.