Originally Posted by Racer Ex

Horse and courses. Doing 3 x 10's isn't going to give you good legs at 7 hours. These are designed to build aerobic capacity. Unless you need to compete at the front end of this ride with truly elite athletes your aerobic capacity will not be much of a factor, think of where your HR will be during most of this event. Muscle fatigue will be a factor though.

What you'll find is that terms like "endurance strength" are used in different context for different goals. If you're going to do 20m intervals at a % of FTP, do them at the back end of a long ride. But mostly you're building a diesel. You want to be good at 7 hours ride 3-4 hours hard. Do the 53/11 thing to recruit slow twitch muscle fibers. Rest as needed.