I had a long talk with a friend today about the running process. Just about every run you go out on follows a pretty predictable sequence. This is extremely important for handling long ones, but what a long run is, has a habit of changing from week to week and that's part of the process too.
My run process goes something like this:
1. Figuring out what kind of run this is
The first part of any run for me is just figuring out how I'm going to feel. Some runs start out with me feeling invincible, running fast, breathing easily, loose. Some runs feel like I'm going up hill from the start. It is really important to do a good internal assessment here. If you don't any lows later on are going to take you by surprise and make things more difficult than they would otherwise be.
2. Settling in
Whether I started out smoothly or struggling the next part of the run is where I establish my pace and do some work on gait and stride. I'm trying to find a steady place that will carry me without too much constant checking in. Sometimes this goes quickly and I find my spot, sometimes I have to check back in over and over until I've got it down.
3. Just going
The truth is there are some runs where this never happens. On a good day this is the majority of the run. On a bad day it never happens and I stay stuck in 2 or go directly from 2 to 4. When it works it's the best. I had one today that by the end of a half mile I was gliding along feeling fast and loose and finished my 8 miles 25 minutes faster than I thought I would, total surprise. Last Saturday I had a 14 mile where I almost quit at 7 because I was still trying to find myself. Making this happen more often and for a greater portion of each run is really the goal.
4. The low
This is the moment when you start thinking about stopping and walking home. It's the moment when you feel tired and down and just want to give it up. Again, sometimes it's just a thought but it can also take over your entire process until you're just fighting that impulse. How well you handle the low has to do with how attentive you were during stage 1, and how well you know yourself and have prepared your strategy. I look out for this moment and use mantras (relax relax relax relax, fast fast fast fast) to get past it, anything to drag my obsessed mind away from chanting at me to quit. Hopefully I move past this moment and either back to stage 3 or on the last phase.
5. Finishing up
This is where you know you're home free. For me this usually comes about 60% done with the run. I know I've broken the back of the distance and I'm just pushing through to the end. I'm not always flying along for this part but I'm usually not fighting to keep moving. The more I run and the longer my long runs get, the longer this phase seems to be. I used to feel this for literally the last 40 yards of a run but these days it might be the last 6 miles of a 12 mile run. It's usually a pretty good feeling and is often similar to phase 3 with a nice rush.
For the longest runs these phases cycle between 3 and 4. If I'm prepared well and lucky enough to be feeling fluid and fast the lows are short and the going is easy. Even on the off days it helps to know my process and what is coming. Amazingly even a 2-3 mile run will cycle in fast forward through these 5 steps and anticipating them gets me through the lows.
Hope these help you with your process.