A fit person may not get faster through targeted training, I'll agree with that.  But an unfit person will definitely be faster after running regularly for 6 months, especially if they lose some weight along the way.

 

Like Kristen and Zelanie, I had huge gains in the first 6-12 months I ran regularly.  In my ~37 minute 5k in May, when I'd only been running steadily for a month, to my sub-30 in October.  Good Luck!

The studies say you are wrong.  A small percentage of the population simply does not respond to training.  They do not get faster.  Mind you, if someone loses weight, they probably will get faster simply because it doesn't take as much work to move their body from point "A" to point "B."

I started with a 6 1/2 minute half mile my first night out.  I ran a 2:28 half marathon two months later.  Six months after that, I ran 1:54 and I was running about 21:30 in a 5K so I went from a half mile at a 13:00 pace to a 5K at a 6:55 pace.  In other words, I nearly doubled my speed in less than a year.  I used to think that anyone could replicate what I did if they were just willing to put in the time and effort but the evidence doesn't support that assertion.  The evidence is clear.

When it comes to training, humans fall on a bell curve.  A tiny minority will improve extremely rapidly.  The vast majority will improve some although there is a large range of improvement.  But, just as there is a tiny minority that will improve extremely rapidly, there is a tiny minority that won't improve at all.

That's not to say that someone in that tiny minority shouldn't exercise.  He/she can still improve things like cholesterol level, blood sugar, and help to manage weight through exercise even if he/she doesn't run faster.

You may get faster....but I doubt you are going to get consistently faster in a week and a half, by the time of your race.  Getting faster takes some work over time with speedwork, speed drills, etc.   So I doubt a week and a half is time to get consistently faster.     That being said, you still may make your 36 goal time.  You said your last 5K was 38:46, so you are not that far off from your  desired race goal time.   With just a week and a half to go, if you can do it, I would do what Baboon said...run like hell.  Practice 'pushing it" for your last mile or half-mile or so and see what happens with your time.  Of course, keep in mind, the risk here is that "speed" can be tough and if you have not gradually built up to it with regular speedwork drills, just suddenly trying to push yourself faster could potentially result in an injury for you (pulled hamstring, pulled muscle, etc).   I would suggest just run this upcoming race as you normally do and pick a 'goal race" farther down (up?) the calender and then train accordingly and smartly for that goal race.

Personally, I HATE speedwork and don't do it.  However, I like hillwork, so once a week I do a really tough hill route.  After a few months of this, I noticed my pace was getting faster.  Not all that much faster, but still, faster than I was.  Someone once said "Hills are just speedwork in disguise" or something like that, and in my case I found out that was true.  So you might think of adding some hillwork as a regular part of your training routine.

Whatever you decide, good luck!

Thank you LRB!  I'll look up some of those training books and start designing my plan.  I was a little frustrated because I was between C25K and more advanced plans for actual racing.

If winter cooperates I should be in good shape for a March 22 race.  If not, there is another local race in April that I am looking at.  The Freihofer's Run for Women is May 31.  5000 entries and an elite field.  It's one big party!