Pre-Marathon Progression Runs
These are harder and longer progression runs that typically involve running at half-marathon race pace or faster for extended periods of time. They are used to briefly stimulate the aerobic and metabolic systems, but without putting either system in too much distress. These types of progression runs allow a runner to simulate the pace and some of the fatigue of a race without complete breakdown that an extended hard effort might bring on.
When: Once or twice late in a marathon training cycle.
How: Run 16 to 18 miles in which the first half is done at a moderate pace and the second half is at 80 to 95 percent of half-marathon race pace.