Tell me about your experience going from a 10k to a half marathon.

I can't speak for everyone (obviously) but it's really my astute opinion that ANYONE can run a HM at a 10 minute mile pace with the proper training.  I think that the proper training would take somewhere in the 2-3 month range if they can do a 5k with the same pace.  With a 10k - probably even quicker than that.

Again, just my thoughts.  If you add ~10% mileage a week (.5 mile to a full mile) - then you'll be able to regularly do the half mary distance easily in 2-3 months.  

some might find that a bit aggressive, others not so much.  

You can make the transition with relative ease by following the 10% increase mpw (milies per week) guideline. Just make sure you have a good enough base.  I'd say if you're currently running about 15-20mpw, you're good to start a beginner HM training plan.

I didn't have much of a running background until I started training for triathlon May 2011.  But I was training up to a 10k for my first Oly last October.  After that race, I took some time off then I followed a slightly modified version of a Hal Higdon intermediate training plan that went for 13 weeks and I finished the race just fine.  I set a goal to beat 2:00:00 and I did by a little more than 5 minutes.  =D

I did a HM about two weeks after a 10k earlier this year. I did the 10k in 7:45-ish pace (I forget exactly) and the HM in 11:00 pace with my Dad. I had NO problem finishing the HM, I could easily have gone much faster (HR barely left Z1).

The key is how long your long runs have been before the 10k. If you've only done 6 miles a couple of times before the 10k then I'd give it a couple of months, if you ran 8 or 9 miles long run during 10k training then you'll get there quicker.

If you're looking at only running, take a look at one of the Runners World plans for a HM and jump in wherever your current weekly mileage puts you (week 4, week 6, week 8, etc.). If you have a race in mind, then Runners world has a training program calculator to get you there. It's the Smart Coach - just follow the link below and scroll down a hair:

http://www.runnersworld.com/topic/0,7122,s6-238-591-0-0,00.html

I did my first 10K race in the first part of December in 59:57 (9:39 pace). I did my first half-marathon in the first part of March in 2:16:30 (10:26 pace). I know I could have run the half closer to 10:00 pace, but I was sort of overcautious about blowing it too early. And it absolutely poured rain on us the first 3-4 miles which changed my expectations about the race to just finish.

Anyway, I had used one of the SmartCoach plans on RunnersWorld.com like somebody else suggested. They are very handy - put it a race date, how fast you want to run it (based on previous 5K or whatever race times)  and it will map out workouts for you with gradual builds in mileage. It isn't fully customizable, but it gives you a good idea of how to build mileage and how long each run should be. 

I had some lapses in my 10 week plan from 10K to half due to illnesses that I didn't run through (wuss!). So I didn't end up at the sub-10:00 pace I was shooting for. But the longest run I did in practice for the half was 10 miles. Amby Burfoot himself told me that was okay, that I didn't need to do 13 in training (he moderates the SmartCoach PLUS forums ) I did make it, but the last 2 miles were rough. My hips really started to hurt, just from the going longer than they had before. So, I would of course suggest that you build up to a 13 mile training run beforehand just to get your body more used to it, but the experts say 10 is enough to get you through the half-marathon.

I did my first HM after only doing 5ks for a couple of years. (And one 10k that I ran the first year, but ran it poorly.)  At the time I decided to run the HM I was probably running 6 miles as my long run.  I increased the distance over about 2.5 months.  I finished comfortably but missed my goal time of 2 hours by a couple of minutes.(got that on the next one)

The biggest challenge was fitting the miles and time into my schedule.  Something I'm working again on now that I've added swimming and biking to my workouts.  Beyond that it was learning what my body needed for hydration and nutrition to manage the longer runs better.  That was something I didn't need to think about for the shorter runs.

The side benefit, my 5k times have improved.

I am presently in this exact situation! Around 5 miles was a long run for me. When I got home the first week of June from a week long bike ride I shifted my focus and began working on my run. Since then I have added 10 minutes to my run each week. Doesn't quite follow the 10% rule exactly, but it's not as if I'm added a crazy amount. This coming weekend I am going to hit 13 miles! I run a 10 min mile pace.

So it took me about two months.

I was in your boat at one point. Always a 10k runner, and never thought I would go further...

Hardest thing was believing that I could do it, and signing up for the first HM took some careful thought.

My training probably wasn't the best but I managed to build up to where I could run the HM with confidence. I was so happy to do my first one!

This broke the doors down and I was no longer just a 10K runner ! (not that there's anything wrong with that)

Of course you know what this means don't you ? You won't stop at the HM !! ;-)

Just for reference from an experienced runner in terms of finishing these races at a similar performance level given adjustment in distance:

- 10k is only minimally more challenging to complete than 5k (doesn't require much more training). For me, it's about 1.2-1.3x as hard.

- HM is fairly more challenging than finishing a 10k but not a heck of a lot harder. If you can do a 10k, you can definitely finish a HM without a ton more training, and if you can RACE a 10k (run wire to wire at a hard effort), you can likely finish a HM respectably now (albeit painfully.) I'd say about 1.3-1.5x harder than 10k training.

- Marathon is MUCH harder than the half marathon. For me, running a marathon at similar performance to my half marathons requires 2-3x the training I need for the half marathon, and feels 3-4x harder in terms of toll on the body on race day. It's actually not recommended to race marathons more than a few times per year if you're going all-out - risk of injury is sky-high.  

From a BOPer's perspective:

I had never raced more than a 5K or done a training run longer than 10K when I decided to do my first HM four years ago at age 55.

I used the Galloway first-timer's plan which was about 18 weeks as I recall.  The plan called for a couple of 30-45 min runs during the week and progressively longer runs on the weekend.  I remember feeling very confident about the race once I had done gotten in a couple of 10 mile runs.

Started the race a deliberately slow pace using a 3:1 run/walk ratio.  Felt good at the halfway point and picked up my pace to do a negative split.

Mark