Train Low, Race High
Fasted training isn't something to use all the time—you can't run as fast on empty, so it's harder to develop speed. During your marathon buildup, gradually incorporate fasted runs into your schedule; do your longest and hardest "on E" runs during the heaviest training block, then scale them back as you approach the event. On race day, your carb stores should be stocked: They still won't last 26.2 miles, but they should last longer than usual.Train on Fumes
How to incorporate fasted runs into a marathon buildup:Weeks 1 to 4
Run one fasted run a week. Start with 30 minutes easy; build up to 60 minutes.
Weeks 5 to 8
Run one fasted run a week. Build up to 75 minutes, and incorporate a 20- to 30-minute tempo run.
Weeks 9 to 12
Run two fasted runs a week. Run one for 30 to 60 minutes easy; run the second up to 90 minutes, incorporating a 30- to 40-minute tempo run.
Weeks 13 to 16
Run one fasted run a week. Run 45 to 60 minutes easy. No fasted run during race week.
More: What to Do the Week Before a Race
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