@JessNewt
I'd say I can draw two thoughts from these statements:
I run for a little over 3 miles in the beginning, but then I struggle to run much at all after.
But my mind is the only part of my body on board, and that is only for the first 3 miles.
Currently on my long runs, I'm between 11:30 - 12:30 min mile when running, and around 14:30 when walking. The time isn't bad, just the longest I have gone so far in this training is 9 miles. I'm concerned how much I'll slow down during 13.1 miles (or if my hip will be bugging me, or if my calves will be tight... random running problems I have experienced occasionally).
1) You are probably training too fast right now. The phrase I use with my runners is "Don't Survive the Training, Thrive because of it." When someone sees a fade in a training run in the absence of external factors (like temp change, wind change, or elevation change) usually it means the training is inappropriate. And the first place I look at when evaluating inappropriate training is the pace at which it's being done. The goal of most every training run is to stick close to training day goal effort/pace and be consistent. So if the goal long run pace for the day is a 13:00 min/mile, and I run 6 miles at 13:01, 13:03, 13:05, 13:04, 13:04, 13:01 then it's a nice consistent pace (assuming this was done on flat ground or minimally a similarly elevated mile for each). But if the goal were a 13:00 min/mile, and I run 6 miles at 13:01, 13:01, 13:01, 13:45, 13:55, 14:35, then it's a sign that the training run was likely inappropriate. Training like the second example gets someone stuck in a mode of surviving the training. The body is doing everything it can to stay afloat. It receives the stimulus (training run) and only recovers from it in time for the next stimulus. Conversely a person in the first example would be more likely to reap benefits from the training. Instead the body would receive the stimulus, recover from it, and then most importantly adapt because of it. The adaptation is what makes us fitter/faster over the long term. But the absence of a fade is not sufficient to define training as good, rather it is sufficient in the presence of a fade to say the training may be inappropriate. So when I see you describe training runs as run for three miles, and then struggle (a likely fade), then it says to me you're probably training too fast at the moment. Many of us go through a similar learning curve when picking up running as a hobby. I use to use a "PR the day" mindset with pacing (and almost always saw fades on long runs). Never yielded race results that I thought I was capable of. I dropped that mindset and shifted to "Train smarter, not harder" and "Train slow to race fast" and my race times improved dramatically.
2) While you may be training too fast currently, you're not likely a 3:12 HM runner (or under ideal training conditions you don't have to be). You claim to run an 11:30-12:30 min/mile during the run portion. And also claim to run for a little over 3 miles before you introduce walk breaks. My previous example showed a 3:12 HM runner is also a 41:44 5k runner. But if you run an average of a 12 min/mile for 3.11 miles, then you run it in about 37:17. Now very few people are going to run a 5k PR and then do another 6 miles after it (9 mile long run), which leads me to believe even a 37:17 5k is selling you short. But someone who has a 37:17 5k under ideal training is more likely a 2:51 HM runner.
But again, probably selling you short on this because people don't tend to run a 5k PR and then another 6 miles. The 14:30 min/mile when walking throws me off though. So if a continuous runner, the long run pace is usually 11-13% slower than half marathon current fitness pace. If a run/walker we do current fitness marathon pace + 2 minutes. In both these cases, a long run training pace for a 2:51 HM runner would be either a 14:52 min/mile (continuous runner) or a 15:38 average min/mile (run/walker). But since the 14:30 min/mile walk pace is lower than both it comes to a crossroads.
Let's say a 30/30 of 12:00/14:30 was an appropriate long run pace for someone. How fast would someone have to be for that to be the case?
With a fitness profile of:
This means to have a ratio of 30/30 with 12:00/14:30, then you'd probably need to be a 30:30 (9:49 min/mile) 5k runner. If you feel that is an achievable time, then the long run splits of 30/30 at 12:00/14:30 is probably close to appropriate. But if you're thinking a 9:49 min/mile 5k seems way too fast, then it likely helps reinforce that slowing down in training is probably a wise long term strategy.
I'm planning my last long run this Sunday. Shooting for 11 or 12 miles. I'm worried if I struggle that it will shake my confidence. Obviously if it goes well, it will have the opposite affect.
Keep something in mind, when I train other runners I do so by duration of a training run and not mileage. So I've got marathon runners that do 23 miles long run max in training, and others that do 11 miles long run max in training. So the absence of a super long run that is close to goal race distance won't preclude you from a successful race day (dependent on all the other training you're doing above and beyond the long run itself). With that being said, if you choose to aim for 11-12 miles for your last long run, then I'd suggest trying to aim for a pace (whether it's run/walk intervals or continuous running) that when you finish the run you feel like you could still go several more miles with ease. So that could be a 12:00 min/mile or a 14:00 min/mile or a 16:00 min/mile. A pace that you personally can be consistent at from the start of the run through the 11th mile of the run. Because a consistently paced run will yield more benefits than a run where your body forces you to fade (again not because of changes in weather or elevation). Additionally, the pace of the run should be nowhere close to what you actually want to achieve on race day itself. As long run pacing for a continuous runner is about 11-13% slower than HM tempo, and for interval runners about 2 minutes and change slower than HM tempo.
