first half marathon (Read 1112 times)

Hi everyone.  I'm relatively new to long distance running so I figured I would ask for some advice.  I've been training for two months for a half marathon that is 5 weeks away and I think it's time I set some goals, or at least think about what pace I can keep.  Last week I ran a 5k (only my second race since high school) to see what I could do and ended up running it in 21:11.  I was happy with the time, though I probably could have ran even better if I slowed down in the beginning (6:19 at mile 1).  

Anyway, plugging that time into one of those racing calculators suggests that I should run my half marathon at about 7:30 pace.  That seems very fast to me, especially since I've yet to even reach 13 miles on a run at any pace.  With the exception of the 5k, I haven't come close to that pace.  How can I prepare myself for that pace in the next 5 weeks?  Or should I set my sights lower?  I plan on increasing my long run to 13 miles 2 weeks before the race, and then doing 10 miles a week before the race.  

Also, I've noticed that the heat has a big effect on my pace during my long runs.  How should I approach the race if it gets to be 80 degrees or higher?  

Are you following a training plan of some type? I think working some race-pace miles during your runs in would be the answer to how you could prepare for running that pace.

I have to echo MilkTruck's concerns about base.  I think most of those calculators assume that you're running mileage to support the distance.  And, I don't know that you can cram endurance in in 5 weeks, but I love being proven wrong.    I don't think those calculators take into account things like high temperatures and grade of the course either.  Unless your acclimated, heat can really change the whole equation.  So, if this was my BFF's first half marathon and it might be 80+ degrees during the race, I would probably tell her to set a pre-race goal of doing the first 3 miles hard but in control (8:15/8:30 pace?) and then trying to run negative splits from there.  (Unless the course doesn't lend itself to something like that, i.e., flat/downhill in the beginning and uphill at the end).  Blowing up early in long races is not fun.  You're allowed to make that mistake once.  Once.

ETA: After looking at your "Random" course rather than your calendar, it looks like you have been doing pretty consistent long runs for a while.  You'll be fine.  Just don't go out too fast.  Especially with the heat. 

IMHO don't get tied up around aggressive goal times to match calculators for your first HM.

 

#1, calculators assume you are as well trained for your goal race as the (much) shorter input race (5K) that you used.  You aren't.

 

#2, you lack experience.  So it is unlikely you will be able to match up to the predicted performance.

 

My opinion, go out just a little faster than you would run that distance in an everyday run.  Accelerate slowly according to feel.  Be very happy when you finish running hard.

 

For perspective, when I ran my first HM I had already been running for 10 years and had just finished running for my university with a 10K PR of 34:18.  I went out around 6:30 pace....not a heck of a lot faster than what I'd call an easy run pace.  I ended up averaging ~6:00/mile in 1:18:XX.  McMillan calculator spits out 2min faster based on my 10K.  No way in heck I could have run that on that day...maybe split the difference, if I got lucky.  But because I was conservative I had a good experience and came back for more, and was far under that is short order.

 

It's your first.  Run it, learn from it, and go faster next time.

All good advise above. I would just strike "...for your first HM" from the first sentence because I dislike race time predictor calculators in general.

What most calculators do is apply a generic decay function (for example 5-6% decay in speed for each double of distance). Someone trained for the mile might have the exact same 5k time as someone who is trained for the 10k but the two runners will have quite different finish times when they both run the mile or the 10k even though this online calculator would consider them identical runners. The difference is that at any runner has 2 main factors that influence race time: top speed and endurance (how close to top speed you can stay for a given distance). A calculator that looks at a result from just one distance cannot separate the two variables.

There are some calculators out there that require you to put in race times at 2 distances. These are a bit better but unfortunately they usually just fit a straight line between the two points to give you your speed as a function of distance. This model works fairly well if you are looking to figure out a pace for a distance between the two points and your two races were only 3-6 miles different in length.

Your actual speed v. distance can be closely modeled either with an exponential or with a natural logarithmic function (because of the noise in your race times, neither will be an exact fit but either can give you a good idea of what pace you can manage). The drawback is that you need at least 3 race distances to do the fit and if your fitness changes significantly over the span of running those two races it will introduce additional error to the function.

The best way to go about racing is to forget about the online calculators. Forget about mathematically modeling your race times. For your first race, just go out as fast as you think that you can comfortably handle. Then make your goal to beat that time at your next race.

IMHO spaniel's last line is just about the best advise anyone can give you about racing any distance for the first time: "It's your first. Run it, learn from it, and go faster next time."

jasmini -- you can join us in the Half Marathon Trainers group here on RunningAHEAD to discuss all things half marathon related, or whatever else comes up.