Step 1: Run your magic mile time trial (MM) (4 laps around the track).
Step 2: Compute your mile pace for the marathon by multiplying by 1.3
For the half marathon, multiply by 1.2.
For the 10K, multiply by 1.15.
For the 5K, add 33 seconds per mile.
Example:
MM time: 10 minutes
For the best possible marathon pace currently, multiply 10 x 1.3 = 13 min per mile.
For the fastest long-run training pace, add 2 minutes per mile = 15 minutes per mile.
Remember to slow down 30 seconds per mile for every 5 degrees above 60 ˚F. It’s always better to go slower on the long runs.
Current half marathon potential is 12 minutes per mile.
Current 10K potential is 11.5 minutes per mile, or 11:30.
Current 5K potential is 10:33 per mile.
In order to run the time in the race indicated by the MM,
you have done the training necessary for the goal: long runs, speed sessions, form drills, race rehearsals (see www.jeffgalloway.com);
you are not injured;
you run with an even-paced effort;
the weather on goal race day is not adverse: below 60 ˚F or 14 ˚C, no strong headwinds, no heavy rain or snow; and
there are no crowds to run through or significant hills.
Note: In your first race at any distance, just run to finish. Run the first two thirds of that race at training pace. Then you can choose to continue at that pace or pick it up a bit if you feel good.