I second this. There's another psychological aspect to me. Training the "let's resume" action of your brain is very important. And doing this alternating smooth to harder is one good way.
https://medium.com/runners-life/how-to-start-running-using-j...
I've had good success with this strategy - it breaks up the monotony of long runs, and overall pacing is accomplished by changing interval duration instead of trying to maintain a precise fixed speed over the entire run.
Unfortunately, I've had no success convincing other beginners to try this method, as the predominant wisdom is that you have to run over the entire duration, and beginners almost always go far faster than they should.
I started with a C25K plan in November 2020 and ran my first half marathon in October 2021. I'm looking at marathons now, it's changed my level of fitness far more than I could imagine.
1. Couch to 5K
2. Beginner 5K https://www.halhigdon.com/training-programs/5k-training/novi...
3. Beginner 10K https://www.halhigdon.com/training-programs/10k-training/nov...
4. Intermediate 10K https://www.halhigdon.com/training-programs/10k-training/int...
5. Intermediate 21K https://www.halhigdon.com/training-programs/half-marathon-tr...
Thanks for the links.
I think training plans depend a lot on what you're wanting to do - I just wanted to complete the distance; I could probably do it faster with a proper training plan but I've found running without worrying about time (too much) to be enjoyable (and I have still got respectable results for my age).