The Filthy 50 is 50 miles with about 2,000 feet of climbing on rolling roads that are mostly gravel with some dirt, through northern Minnesota’s lakes country in early October. Expect fall conditions in the 40s to 60s with a chance of rain.

This is an eight-week plan for riders working with four to six hours a week against a job and everything else. Most of that limited time goes toward steady riding on rolling terrain and getting used to a full day on gravel, so the hours you do spend match the distance and the surface the race asks for.

WHAT'S INSIDE

• Structured workouts on your calendar, with real power and heart-rate graphs


• Strength work built in, with video walkthroughs


• Weekly notes from me, plus the Gravel Grit mental program


• A testing week, so the plan runs on your real numbers


• The full Filthy 50 guide — terrain, gearing, fueling