This is a good thread and deserves a bump. Could you elaborate more on paces? I know it is effort based but picturing LT pace would be somewhere along the lines of between Jack Daniels T pace and I pace. If you move it to treadmill for example and say are looking to duck under 19 for the 5k, there would be a lot of workouts in ranges between 9.5mph and 10mph?
I don't think it's beneficial to get into the weeds about specific paces for specific people to be honest. I think it should be about feel and it probably varies pretty wildly from person to person depending on all sorts of factors. If you're on a treadmill you're certainly more likely to be conscious of your exact pace at any given time, but to the extent that you can ignore it you definitely should in my opinion. If you're running outside and have a GPS watch, I strongly recommend turning off auto-lap and changing your view to read time only so you aren't even tempted to figure out your speed at any given time. That change has made a huge difference for me personally.
Even with feel I'm sure it can vary from person to person based on whether you're better at longer or shorter distance races. Like someone who is more of a mid-distance type will probably run a tempo pace that is slower than someone who thrives on distance work but it will feel the same for both and be more beneficial than either of them trying to modify their paces to match the other.
I'm personally better at shorter distances so what I say may not be true for everyone but here is how I feel the paces:
- Tempo for me is a pace that feels quick but that I know I could sustain for 90 minutes to 2 hours straight if I was in a race. It's not the most comfortable pace but I could absolutely hold it for a long time.
- LT for me is a pace that starts to feel a little uncomfortable but you could still definitely hold for I'd say 30 to 40 minutes on the hard side and maybe a little over on hour on the easy side.
Looking at my GPS data after the fact, these paces have varied a lot depending on how I felt that day. From close to my actual 5K pace sometimes for the shorter reps and slower than my half marathon pace when I was feeling crappy on the longer reps. As long as the effort felt right though, the workout served its purpose.
It's just my opinion but I feel like focusing on the exact training paces you think you need to hit to run specific race times probably hurts you a lot more often than it helps. Sometimes you're giving yourself unnecessary limits that are holding you back from what you truly can achieve and sometimes you're doing workouts faster and harder than you should be and not getting the benefit you're really looking for. Using Daniels as an example for me, whenever I've tried to hit the prescribed T pace for mile reps say, it's always felt like a race effort for me and even when I had recently raced a time that the calculator says justified that specific T pace. Those paces are generic and may work for the average but most of us aren't exactly average.
I hope that helps. Remember though, I'm no expert, just a guy trying to figure this stuff out like you. These are just my opinions and what's worked for me personally. I might be way off base so please take it all with a grain of salt and do what you think is best for you.