Mileage Minimums
These are rough guides. Many people can be successful on less and some may need more. The intent is to give you a set of relations that work for most people most of the time so that you can frame your own plans and expectations.
Minimum weekly mileage to finish or perform well in a race:
For a 50K: 30 miles per week to finish and >50 miles per week to perform well, for at least 3 weeks before your taper
For a 50M or 100K: 40 miles per week to finish and >60 miles per week to perform well, for at least 5 weeks before your taper
For a 100M: 50 miles per week to finish and >70 miles per week to perform well, for at least 6 weeks before your taper