No, this isn't a blog about the use of Lysergic acid diethylamide while running. LSD is a running acronym for Long, Slow Distance. There is a school of thought in running circles that says Long, Slow running makes a Long, Slow Runner. They of course mean, that if you spent all of your time running slow (because of preparing for Half-Marathon to Ultra Marathon races), your body will become accustomed to the mechanics and stride of that type of running. This leads to losing speed and any type of faster pacing that would give you the ability to finish the race with a quicker time.
I don't buy that argument as an absolute truth, but there are some elements of truth in it. It is hard to run a quick 5K when your training consists of mostly long runs. But the main reason for long runs is not for speed, it's for endurance.
After finishing Grandma's, I've been looking back over my past finishes at Marathons and making a connection between the pace of my long runs and the pacing of my overall marathon time.
As a general rule I've noticed that my average pace that I can run in the Marathon is no faster than one minute per mile for my average pace in my long runs. In my fastest Marathon, I ran my average pace that I ran in my long run for 16 miles, and then a minute faster for the last 10 miles.
Hal Higdon has a fundamental that says "If you want to run fast, you need to run fast." This pertains to the 5K as much as the marathon. If you want to run a planned predicted pace in the marathon, you have to practice it by running within 1 minute of that pace in your long runs.
I know this bucks a lot of the running guides out there that say you should run your long runs at planned predicted pace (PPP) plus two minutes per mile. But from running 20 plus marathons, I can say this isn't fast enough. That said, the PPP plus two minutes is great for building up endurance to run that distance, but not that pace.
So as you start your plans for fall marathons, take note. The LSD will affect your marathon if they are not done at a speed within one minute of your PPP.