10K
I don´t like to advise in an individual base, or a individual case. Each one is a specific case, i ignore completly your running profile, your biography - in what running category and talent and competition categories you are, what moment of your running career you are - your training schedules and what´s unique in you that would make me change from my limited concepts and my training discrimination (my standard workouts)to fit in your individual case.
and as you know the train is holistic, and to advise in a single workout direction, we need to combine that your particular workout answer - about how to run interval training/aerobic power short reps/short active pauses - with all the rest of your 10kilo training. I also pay a lot of attention to rest and what we call - invisible training -from your training facilities to your social life.
Resuming i´m able to send such an advise only if i coach you directly.
But, i don´t want to run away from your question, and i want to profit your ask - a good one ask - to make you know my personal opinion about that kind of workouts.
First. What you said "...I am really weak at long intervals" you aren´t a unique, single, solo case. Oh no. First you may understand what is the reason that you are weaker in that intervals than the other runners ? Lack of endurance? Lack of mileage training? Lack of resistance ?
To much workouts in short reps ? Phychologic weakness to cover log distances in a track (boaredom laps)? Start too faster in first reps that enables you to cover the last reps ? Shorter interval than it might be (like 1min intervals)?
When you find the reasons of that weakness - is when you try to focus in the improvement of that your lack. But since i´ve seen someone like you - lackness in long reps - that´s the opportunity to use a lot that short reps/interval training aerobic power.
My concept formula is this one:
All is done progressively. From short reps. distance to a little longer, from less total distance to longer total distance, from long intervals to shorter intervals.
Only when you felt confortable in an workout plateau is when you think about to change for demanding/hard workout.
Let´s think that you estimate that your actual condition is a 30:00m in 10000m. one important detail, when you estimate race Pace for your event distance that you go to compete right away you can´t live with HISTORIC PERFORMANCES. This is a big mistake, to have historic performances or PB´s as a referencee. may be you did that your PB in the past, but now you are distant from that PB - then when you estimte your race pace - that´s estimate in your actual shape condition, not past performances.
Ok, your estimate condition is a 30:00.
Start with short distance sets - 300m, and in te future then move on to 400m or 500m 600m reps. Why you move to short reps to longer reps. the reason i explain earlier on - tyraining modulation goes to the extensive direction in middle and long distance approach - to spend a longer period of time in pace zone.
My key formula is this one
10X300m(or 400m or 500m or 600m)/Race Pace event distance less 5% to 10% race pace=300m RP=54sec less 5%(2.7)=51.3 average.
The recover that´s in 50% race pace + 10% to 20% RP to cover 100m or 200m ahead on track. In your 300m example
50%RP+10% for 100m ahed on track =36sec+3.6=39.6sec and 50%RP+15%=46.8sec. In first attemps use conservative recover, that of 50% pace + 20%. Despite i said conservative that´s hard as well. May be you like to rest for 200m - that´s easy than 100m, despite that´s the same pace and also imcomplte receover, you have more time to recover. so mthat´s easy.
Further up, when you fell comfortable move up for longer reps, in the same logic. This aren´t easy workouts, it needs some period of adaptation, especially for the runners that are used to do reps all-out or very fast pace. This aerobic power workouts ´despite that aren´t in a faster pace that hard to complete. They aren´t very intense but a great "density" because you need to manage short/active pauses. Don´t try this workout more than once a week.
Then, as soon as you understood this workout model, individualize your workout to create a your "standard". Later on, you don´t need my advise, no one knows - as you know - what´s the proper pace you may use that, what is the best active rest time duration etc. You did broke my fix rule/formula to use your one, but influenced by my advise.
2 more advises.
1/Don´t think that i only prescribe this workouts. We also need to use explosive reaction. fast pace, all out pace workouts, but for those i use short bouts with complete recover. A 1500m,3000m,5000m or 10000m or even HM or Marathon runner they may also train SPEED, all out pace, explosive reaction, no matter what´s the workout model/design - fast pace, long/complte recover.
The fact that you are weak in that your "8-10 x 1k
4-5 x 2k", i don´t advise you to give up. My advise is this one, seems me logic, why are you confine to the number of reps and the pace or the interval we use the people does.
May be you think this simplistic but that´s my advise - you you don´t limit the number of reps and isntead OF 8-10x1000M why not do try just an half 4-5X1000m, or 2X2000m in the same race pace. What´s the recover ? I don´t know but why you don´t essay to run that in a long recover period 5 to 10min pause ? And even with my advise to reduce the total distance and to use a longer recover you aren´t able to complete that workouts why don´t you redice the pace just to 90% race pace? Please, don´t be fixed in the standard workouts you know that the other they do. Lots of times people thinks that if you are n´t able to train the same and similar to the other you aren´t able to improve - which isn´t true. Open your mind. Be flexible. Don´t use fixed rules.