How to avoid the wall in the half marathon

by Alan
(St Kilda, Melbourne Australia)

How does one avoid the wall - in the half marathon in this case ?

"Hi Marius,

I finished my first 100 day plan but instead of a marathon I ran a half marathon yesterday - my goal is Berlin in September and I want that to be my first full marathon.

I was on track for a 1:45 finish time and was steadily running 4.57/km up to 16Km when my legs 'bonked' and i had to slow dramatically - at some points walking.

I finished in 1:50.24 (a 7 minute PB) and during the race, ran my fastest 10Km _ever_ (I was very happy). With approximately 118 days approximately to Berlin, I am keen to learn from what happened yesterday and how best to avoid it.

I have been closely following the 4 hour plan and have only missed one or two sessions - most recently the last 4 hour long run which I chose not to do, as I knew I was running the half marathon. I have substituted some other running events (15Km's +) on weekends in lieu of some of my long runs.

I am by no means disappointed - in fact, I am very, very happy and this has been a great opportunity to learn and 'fix' what needs to be done in my second 100 days.

I have been using the 100 day plan based on pace/km: Should I switch to heart-rate instead?

I look forward to hearing your advice.

Alan

Answer: Hi Alan, and first of all - congratulations on a 10km PR during (!) the half marathon.

Much of the answer to your question goes into pacing. Since this gave you a PR in the 10k during that half marathon you may have over-run it early on based on the current shape you have.

Parts of the reason why you see a 5k race a 10k race a half marathon race and then the marathon race in that particular order of the 100 day plan is to use these as "pacing tools" leading into longer and longer races. Meaning : you want to use the previous shorter race - plug it into the 100 day marathon calculator and then run the up and coming race according to that pace.

Now, this is how to approach it now :

1) When you use the 100 day plan leading up to Berlin, make sure that you use the previous shorter race results as a "pacing tool" as described above. This will allow you to really know "where you are at"

2) IF you find out around week 10-11 that you cannot reach the time planned in the half marathon (that will give you a sub 4 hrs marathon) you want to adjust this goal according to that. You can wait until that time though and really go for it, but if the half marathon shows you that you still have 10-15 minutes to go you want to respect that instead of risking hitting the wall in the marathon.

3) I strongtly suggest you read the nutrition guide in the 100 day marathon plan if you haven't looked closely at it yet. The tips I give you there really works well - so if you have a few pounds you can lose then this may help you with those minutes down in time as well.

4) I would also use heart rate monitor as well, like you suggest. Some have better effect of using this, it gives better control and it is worth a try - especially now that you are well used to the 100 day plan and have been through most of the sessions.

I wish you all the best and again, congrats on running your best ever 10k during the half marathon.

regards,
Marius

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