How long would it take to go from 1:30 HM to 1:20

To go from 1:30 to 1:20 takes negative 10 minutes.

Seriously though, none of us can really tell you. You're new to running, so still making beginner gains. You could get there on your next race, or you could never get there. Just keep running, find a running group to train with that has some faster people and slowly work your way up the group as you get faster over the next year or two.

I'm sure it's possible, but that "talent" factor is so hard to predict. I know I tried and failed to something similar. I ran 1:27:40 in fall and tried for sub 1:23 in spring, and ended up running 1:26 with a significant positive split. I was on pace at 10k (39:30) and fell apart around 16km. I was also age 38 but I don't think it mattered.

I ran very consistent 65km per week from November into March, with a weekly 20km 'long' run where I always negative split the second half. I did no other structured training, and feel that was my big issue. I never ran 3:55/km in training, so how did I think I'd do it for a half?

Hopefully someone else can recommend proper workouts, and maybe you can have better success than I did.

(I subsequently got divorced, quit running, gained weight, and now probably couldn't do a half in 3 hours).

Hard to say.

In my personal experience I have progressed the below.

November 2018- 1:32:06, 30-35 MPW

April 2019- 1:25:50, built base, 40-50 MPW then injured and final month was 35-40

Have been putting in 60-65 since July and I feel 1:20 is easily within reach with a recent 10K (35:34) projecting 1:18 for me.

Given it was your first I would say if you up your mileage a good bit you could reach it.

Thanks all.

My main target would be to go sub 1:25 at the next attempt. Anything extra minutes that I could shave off would be a bonus. (In fact, I was aiming for sub 1:35 at this HM and ended up 6.5mins faster)

I guess it is quite difficult to know at this stage. I will focus on the aerobic base building for now and see how I progress over the next 2-3 months.

Most of my miles are done in my "run-commute" after work. I would normally run 4 times a week during weekdays (8km each) at a easy or steady-ish pace depending on how my legs feel. On weekends, I would normally do a 15-20km long run at a steady pace with negative split on Saturday and a easy 5km recovery run on Sunday.

I do think the jump to sub 1:20 is rather large, but like others accurately said, it's hard to predict at such an early point in your running.

My progression went from 1:31:32 off of very little training (20-30mpw, one 15 miler) in 2011, then more miles and ran 1:27:30 in 2013 (avg'd 40mpw this year); 1:24:59 in 2014 (avg'd 44mpw this year) and then 1:21:10 in 2018. From 2015 to 2018 my mileage was consistent, right around 2250mpy (43mpw) but I added weight lifting which I think helped a ton. Otherwise it was just a lot of consistency and no magic workouts. Tempos, hills, k and mile repeats, long runs.

Good luck.

Took me 2 years (I’m 49)

1:29 a

1:25 b

1:21 c