I ran the same marathon time on the Pfitz 18/55 plan as I did when running my own 18/40 plan. 3:30 in both cases with 1:39/1:51 and 1:38/1:52 splits.
I know the Pfitz plan has a lot of support on this site but is it possible that it is not the right plan for my particular profile? This is not meant to be a knock on the Pfitz plan, rather I am trying to figure out why my marathon performance was exactly the same when running 15 mpw less over an 18-week cycle.
I have always gotten slower the longer the distance. For example, my half marathon PR of 1:28:50 equates to a 3:07 marathon per McMillan. Nonetheless, my marathon PR is 3:30 (2x, with 2 others in the 3:40 range) despite going out at 3:20 pace (significantly slower than McMillan would predict).
This trend was apparent even 12+ years ago when I was a “serious” runner with more meaningful mileage (70 mpw) and PRs in the 400/800/1600/3200/3 mile of 52/1:56/4:27/9:55/15:30. My 800 time was always my best PR and I tend to be more of a “fast twitcher.”
My half marathon PR was run on 35 to 40 mpw. I did not have the chance to run a half in the course of running the Pfitz 18/55 plan but my training paces for long runs, tempo runs (6 to 10 miles) and VO2 max workouts during the Pfitz plan build up were all consistently 10 to 15 seconds per mile faster indicating improved fitness.
On top of all that, my endurance seemed notably better and I was lighter (3 to 5 lbs). I finished 20 mile runs stronger, mid-week 12 mile runs felt easy and a 10-mile run at goal marathon pace in the course of a 55 to 60 mile week was a piece of cake.
Questions as I try to isolate the reason for my lack of improvement:
-Do I lack the general aerobic strength necessary to run an evenly paced marathon? I faded hard in the last 8 miles. While I did four 20-mile runs in training, I think more runs in the 22-24 mile range would have helped build the aerobic and muscular endurance I needed. My longest long run was only 2 hours and 40 minutes, 40 minutes short of my goal pace.
-Do I need longer MP efforts? Again, I faded hard in the last 8 miles. My long runs of 16 to 22 miles were generally run 15 to 30 seconds slower than goal MP. Outside that, I did three “fast finish” long runs with 12 to 14 miles at goal MP. I completed these runs without much difficulty. Should I have been doing 18 or more miles at goal MP to simulate the late race effect of glycogen depletion and train my body to burn fat?
-As a runner more suited to shorter distances, am I merely destined to be an extremely mediocre marathon runner? Not looking to get to a level consistent with my HS prs, but I would like to run a reasonably good pace for a hobby jogger that works 60+ hours per week and runs 5 days per week which to me equates to a BQ.
-Is my off season mileage entirely too light to even expect to have a good marathon performance? Outside my 18-week buildup, I average 30 mpw for the remaining 34 weeks of the year.
The late race fade is certainly not unique to me given all the talk about Ritz and Teg, but it also does not seem like it should be that hard to fix. Plenty of people have it figured out based on the number of people that run evenly paced marathons.
