The following is my mindset when I start working with a new to me runner, and can be attributed to looking at one's self potential path over the short and long term.
What's their potential?
One of the easiest places to start is with potential. Like it or not, training can only take each of us so far. There's virtually no chance for any of us to go from where we are after years of training into Olympic level athletes. So each of us has a "cap" so to speak of about the best we can reasonably expect. A good average for that is a 20% increase in Jack Daniels VDOT value. Now, that's an average value. Which means there will be people who improve more and some improve less. But even in my own limited work in comparison to the vast population, I see that average number often. So how is it calculated?
The best place to start is by typing in one of your earliest 5k races into the Jack Daniels VDOT calculator (
link). Doing so will output a VDOT number. For instance, if I type in 30:00 min 5k, then I get a value of 30.8. So then what's a reasonable average potential cap for someone who starts out as a 30 min 5k runner?
30.8 * 1.2 = 37.0
So then I'd go back into the calculator and see what a VDOT of 37.0 is equal to by brute forcing the calculator until I get a matching value. It's a 25:45 min 5k. So a reasonable expectation is to see a drop of about 4-5 min when this person reaches their peak. Going from a 9:39 min/mile 5k to a 8:17 min/mile 5k. Does it always have to be that way? No. Again, some people see more or less. Here's my progression:
My very first training run when I started in June 2012 was around a 36 min 5k. First race a 4:50 marathon (Oct 2012). First HM on a known short course with adjusted time around a 2:00 (April 2013). So that's a starting VDOT of 24.7-36.5. My peak has been the 2018 Dopey 10k in 39:54 (VDOT 52.1). So on the high end, I've improved my VDOT by 110%, and on the low end 43%. So just to show an example, it's possible to exceed that 20% VDOT improvement value.
On the flip side, I've seen others work as hard as I have using similar training plans, career miles, and all the other fixings and not see near the same improvement as I have. I'm very lucky, and to this point don't have an answer as to why one is above the average in improvement and another not, when following a similar path. But one way to figure out one of the best ways forward is to look for what plans have worked well and which have not and look for similarities/differences. Look at volume, effort levels, circumstances around the races, etc.
How long does it take to hit that long term potential?
For endurance races, it's on the order of years. Another good average, not perfect, is around 7,500 career miles of good training. After about 7,500-10,000 career miles, you're likely as good as you're going to get. I hit 7,500 career miles in early 2017 (about where that small green dot is). I've tried a lot of different training techniques since then, and every once in a while I'll catch lightning in a bottle, but for the most part I've been pretty much the same since then. I'm coming up on near 20,000 career miles with not much difference since 7,500. These days it's more about maintaining than it is expecting to see much more in terms of improvement.
Once we know the reasonable potential, and what the goals are, then we can figure out what's the best way forward.
Needs Endurance (most of us)
In my experience, about 90-95% of the people I work with fall into this category. Most of us are trying to improve our 10k, HM, M times. And more often than not, to meet that end you need more endurance. But how do we determine which is the best path forward. I start off with typing in some recent race times within the last six months. Here I'm trying to assess where current fitness is. Let's say someone has a goal of a sub 2 HM, and has recently run a 2:05 HM. According to the VDOT calculator, the following are the equivalents to the sub 2 HM.
If we do a mile test, and they run a 7:45 min/mile or faster, then they already have the requisite speed to run a HM in under 2:00 when fully trained. For them, I'd aim for more endurance work. More HM tempo (9:09) work to get them comfortable with that particular pace. More work just slightly faster and slower than HM tempo to have them understand how the early and late race should feel. Some blind tempo runs where you're not allowed to look at your watch for feedback and you have to "feel" the pace.
Now one way to improve speed is simply more endurance as well. We all have our caps in terms of the weekly volume we can tolerate. I've seen some runners who've tried 6-7, 7-9, and 9-11 hrs per week, and done better at different ranges. Some are better at 6-7 and some are better at 9-11. Only way to know for sure what type you are is to try with a well written/structured and safe training plan to see what happens to your body, and only with a proper volume buildup to it. Don't go from a max of 6hrs per week into a training plan that maxes at 11 hrs per week. A proper long term approach is needed.
Need Speed
If we do a mile test, and they run a 7:45 min/mile or slower, then they need more speed in order to hit that HM time. Now it depends on how far away they are. If they're running a 8:30, then it's going to some work to get down there. Maybe more than a single training plan can yield (more on that coming up). So they'll probably need two training plans or 6 months to be closer to hitting that sub-2 goal. If they're closer, then we might try blending the speed and endurance into a single plan to hit it sooner.
When I'm prescribing speed work, my first go to is the Jack Daniels 3rd edition mile or 5k/10k plans. I've seen tremendous progress for myself and others using that system. It really helps get you comfortable with being uncomfortable. The issue for most is that the Jack Daniels plans are written in a weird format (with distances/times/paces) that can make it overly complicated at first. You really have to sit down with the book and understand what he wants you to accomplish in the workouts. I've simplified it based on the understanding that deep down all of our physiological systems work similarly when it comes to effort and time. So if you and I do a 45 sec fast pace + 90 sec rest at a relatively high effort, then in a vacuum we're doing a similar workout regardless if one of us is doing 100m and the other 200m. So converting his workouts into time based makes it easier to translate to people of all paces.
We know the reasonable expectation for the long term, but what about the short term?
So if it takes years to hit your potential, what's a reasonable expectation for a single training plan? Again, another good average is around 3-5%. Sometimes more and sometimes less. That's going to have a lot to do with how long you've been training for. Because as the flat line suggests, it gets harder and harder to make smaller and smaller gains. But let's go back to the 2:05 HM with the sub-2 goal. What's a 5% gain in a single training plan?
2:05 * 0.95 = 1:58:45
So depending on a lot of factors, it's possible to go from a 2:05 to a 1:59. You can expect less gains if you're later in your journey and more gains if you're early.
For endurance, the first real kick into overdrive came when I did the Hansons Intermediate (blending of Beginner and Advanced) plan in 2015. Made tremendous improvements on my marathon time as it relates to other race equivalencies.
For speed, I always go back to the Jack Daniels 3rd edition mile or 5k/10k training plans because I saw an unexpected improvement. The 5k/10k plan was in early 2017 at that small green dot (VDOT 47.2 and 10k of 43:25), and then after a single training plan was a 19:29 5k with VDOT of 51.4. That was a 8-9% improvement in VDOT and 5k performance. A tremendous improvement off a single plan, and even more impressive coming so near that 7,500 career miles.
Now for a while, I was an odd duck. I could do really well comparatively in 5k, 10k, HM, but never the mile. My mile time was always slower than the others. So in 2020 I did a Jack Daniels mile training plan and was able to finally lower my mile time from 6:02 to 5:42 (VDOT 51.3) but still not quite the same performance as the other VDOT PRs.
Now it's important to note the final caveat. In general, the online race equivalency calculators are not good for setting reasonable marathon race expectations. The values outputted generally fall into a value that only about 6% of people achieve.
So going back up to that now sub-2 runner and the screenshot with equivalencies. They may now have their sights set on a 4:07:42 M time because that's what the Jack Daniels calculator says they can do coming off their 2:00:00 performance. But the truth is, only about 3-4% of 2:00:00 HM runners will hit a 4:07:42 M time based on a large recreational runner population data set (
link). So based on that data set, what's a better expectation for our 2:00:00 HM runner?
6% of sub2 HM runners will run a 4:10
10% of sub2 HM runners will run a 4:12
25% of sub2 HM runners will run a 4:17
50% of sub2 HM runners will run a 4:25
That's a big difference, no? The race calculator says a 4:08ish, but the average sub2 HM runner will actually run a 4:25. So those online race calculators tend to set unreasonable expectations for M goals.
So like I said, that's how I approach goal setting, potential, long term gains, short term gains, when I'm discussing these things with people I've never yet worked with. It kind of helps see the roadmap I take mentally with trying to help others achieve their goals. As always, reach out and I can try and talk you through what I'm seeing in the data.
didn’t 
I would love to get a HM of 2:30 for a POT someday, but it probably won't happen for another few years. You're doing great!
) and then I realize that fixating on the numbers does rob me of the joy of actually running. So I hope you continue to run healthy and find your joy in it (whatever that looks like). 
