So you have a 50 Km trail race planned and you signed up for it about four weeks in advance. You actually ran the 50 Mile course there last year and enjoyed the scenery, the race, and you placed 4th overall. This 50 Km run is in preparation for a 120 Km+ race that is coming up in 3 weeks and you are looking forward to testing your fitness. As a matter of fact, you have been doing long runs on this very course for 6 weeks leading up to it.