Yep, that Casey Jones. As in "Casey Jones you'd better watch your speed." We stayed up late last night so I elected to sleep in and skip the group run this morning. I saw that the workout was a warm up, 4 miles at MGP and a cool down so I headed out to do it on my own. First of all, I AM NOT A METRONOME. The only race I have ever logged consistent mile splits is the Congress Ave Mile. In a typical marathon my pace can vary by as much as a minute per mile with most of the miles within a 30 second range. So what is my MGP (marathon goal pace)? I plan to run between 3:05:00 and 3:10:00 at Boston. Even paces would be would be 7:04 and 7:15 per mile. Even effort on the Boston course predicts a pace spread of 6:43 to 7:40. So, in practicing MGP what should I run? I decided to just try to run 7:00 miles for the 4 mile MGP segment today. My splits for those 4 miles were 6:35 6:48 6:42 6:38. Casey Jones, you'd better watch your speed.