Ran my first half marathon, why did I crash & burn?
Discussion
Bit of background, 2016 I was a fat mess, aged 44, did no real exercise. Started parkrun and a bit of cycling. Did ok up until 2018, then slipped a little.
Got back on it last year, then this year really stepped it up - 5k time now 24.35, 10k time 56.24, nothing spectacular but I'm proud of it.
Thought I'd try a half marathon, to see if I could do it. Yesterday at Dorney lakes so nice and flat!
Training wise - mainly a long slow run of 10-20km, once a week, plus a faster weekly 5k and a flat out parkrun. Still overweight at 13.5 stone but 3 stone less than in 2016. I'm in 5k and 10k pb form. Cycling a a lot.
I hoped for sub 2.10, secretly desired sub 2.00 but knew it was a risk trying that pace for my first attempt (lol).
Set off, felt good, gel every half hour plus some salt tablets now and then. Pace was too fast initially at between 4.40 and 5.10 so slowed it to 5.30-5.40. Found it very very easy, and stayed at that pace, trotting round, actually set a new 10k pb at 55 minutes or so.
Still felt great til 13k, leg started to feel a little sore (piriformis) toes starting to get a bit blistery, but still running 5.40 or below and feeling fine.
16k arrives, I just die - no energy whatsoever, pace slips and slips, 5.50, 6.10.6.30 and even a 7.00. Cardio felt fine, it was just like my battery ran out.
So was it that the pace was too high to start? I finished at 2.04 which overall I am happy with but it was such a sudden crash lol.
Oh, and I will never attempt a full marathon, the thought of that being half way makes me shudder, I'll stick to 5k/10k and the odd half!
Got back on it last year, then this year really stepped it up - 5k time now 24.35, 10k time 56.24, nothing spectacular but I'm proud of it.
Thought I'd try a half marathon, to see if I could do it. Yesterday at Dorney lakes so nice and flat!
Training wise - mainly a long slow run of 10-20km, once a week, plus a faster weekly 5k and a flat out parkrun. Still overweight at 13.5 stone but 3 stone less than in 2016. I'm in 5k and 10k pb form. Cycling a a lot.
I hoped for sub 2.10, secretly desired sub 2.00 but knew it was a risk trying that pace for my first attempt (lol).
Set off, felt good, gel every half hour plus some salt tablets now and then. Pace was too fast initially at between 4.40 and 5.10 so slowed it to 5.30-5.40. Found it very very easy, and stayed at that pace, trotting round, actually set a new 10k pb at 55 minutes or so.
Still felt great til 13k, leg started to feel a little sore (piriformis) toes starting to get a bit blistery, but still running 5.40 or below and feeling fine.
16k arrives, I just die - no energy whatsoever, pace slips and slips, 5.50, 6.10.6.30 and even a 7.00. Cardio felt fine, it was just like my battery ran out.
So was it that the pace was too high to start? I finished at 2.04 which overall I am happy with but it was such a sudden crash lol.
Oh, and I will never attempt a full marathon, the thought of that being half way makes me shudder, I'll stick to 5k/10k and the odd half!
Your early pace was way too hot. 4.40-5.10/km equates to 1h 38 to 1h 49 for a HM. Online calculator suggests that based on your 10k time, 2h 04 would have been a good target which is about 5.55/km.
If you go out too fast in any endurance event it simply won’t matter how much you fuel - you will die a horrible slow death at some point before the finish. Been there, done that!
My advice: keep working on your 5k and 10k times. Keep doing your long slow runs. Find an online pace calculator and project your HM time from you 5k and 10k pbs. If the 10k projection is materially slower than the 5k one then chances are you’ll want to aim for a slightly slower HM pace than the 10k suggests (short reason: you’re better over shorter distances and performance drops off disproportionally the further you go. Not at all unusual in novice distance running).
Then at your next HM stick to your chosen pace religiously. It will feel laughably easy to begin with. Less so in the final quarter. But if you finish with gas in the tank that is a much better outcome than blowing up before the finish.
Good luck, and stick with it!
If you go out too fast in any endurance event it simply won’t matter how much you fuel - you will die a horrible slow death at some point before the finish. Been there, done that!
My advice: keep working on your 5k and 10k times. Keep doing your long slow runs. Find an online pace calculator and project your HM time from you 5k and 10k pbs. If the 10k projection is materially slower than the 5k one then chances are you’ll want to aim for a slightly slower HM pace than the 10k suggests (short reason: you’re better over shorter distances and performance drops off disproportionally the further you go. Not at all unusual in novice distance running).
Then at your next HM stick to your chosen pace religiously. It will feel laughably easy to begin with. Less so in the final quarter. But if you finish with gas in the tank that is a much better outcome than blowing up before the finish.
Good luck, and stick with it!
Sounds very much like a energy crash. But you said you were taking gels. Did you test your gel strategy before the race?
Its quite a short amount of time to crash and burn, possibly you were going to hard and not fuelling enough. Also sounds like your training might be a bit too full on, you should do most of your training at an easy pace, sounds like you are doing a long run and two hard 5k sessions. Only well trained runners can handle multiple hard sessions a week.
Also as Muzzer asked, did you taper?
Its quite a short amount of time to crash and burn, possibly you were going to hard and not fuelling enough. Also sounds like your training might be a bit too full on, you should do most of your training at an easy pace, sounds like you are doing a long run and two hard 5k sessions. Only well trained runners can handle multiple hard sessions a week.
Also as Muzzer asked, did you taper?
Muzzer79 said:
Did you taper before the event?
I would potentially have done more weekly miles than you, but it sounds like you were over-tired rather than anything else.
Could just have been a bad day.
Did you eat well the day before and on the morning of the event?
I ate well the day before, didnt eat very much on the morning other than a porridge bar as I dont tend to each before running.I would potentially have done more weekly miles than you, but it sounds like you were over-tired rather than anything else.
Could just have been a bad day.
Did you eat well the day before and on the morning of the event?
Tapering - I'm new to this but the week before I backed off the exercise generally, just a slowish 5k and I paced a 30 minute parkrun the day before.
BlackWidow13 said:
Your early pace was way too hot. 4.40-5.10/km equates to 1h 38 to 1h 49 for a HM. Online calculator suggests that based on your 10k time, 2h 04 would have been a good target which is about 5.55/km.
If you go out too fast in any endurance event it simply won’t matter how much you fuel - you will die a horrible slow death at some point before the finish. Been there, done that!
My advice: keep working on your 5k and 10k times. Keep doing your long slow runs. Find an online pace calculator and project your HM time from you 5k and 10k pbs. If the 10k projection is materially slower than the 5k one then chances are you’ll want to aim for a slightly slower HM pace than the 10k suggests (short reason: you’re better over shorter distances and performance drops off disproportionally the further you go. Not at all unusual in novice distance running).
Then at your next HM stick to your chosen pace religiously. It will feel laughably easy to begin with. Less so in the final quarter. But if you finish with gas in the tank that is a much better outcome than blowing up before the finish.
Good luck, and stick with it!
Ah I glossed over his pace figures, yeah that was far too fast. Half marathon is a very different beast to a 5 or 10k. My PB from a few years the first 12k felt very much like a training run, nice and easy, then from there turned it up a bit every few minsIf you go out too fast in any endurance event it simply won’t matter how much you fuel - you will die a horrible slow death at some point before the finish. Been there, done that!
My advice: keep working on your 5k and 10k times. Keep doing your long slow runs. Find an online pace calculator and project your HM time from you 5k and 10k pbs. If the 10k projection is materially slower than the 5k one then chances are you’ll want to aim for a slightly slower HM pace than the 10k suggests (short reason: you’re better over shorter distances and performance drops off disproportionally the further you go. Not at all unusual in novice distance running).
Then at your next HM stick to your chosen pace religiously. It will feel laughably easy to begin with. Less so in the final quarter. But if you finish with gas in the tank that is a much better outcome than blowing up before the finish.
Good luck, and stick with it!
BlackWidow13 said:
Your early pace was way too hot. 4.40-5.10/km equates to 1h 38 to 1h 49 for a HM. Online calculator suggests that based on your 10k time, 2h 04 would have been a good target which is about 5.55/km.
If you go out too fast in any endurance event it simply won’t matter how much you fuel - you will die a horrible slow death at some point before the finish. Been there, done that!
My advice: keep working on your 5k and 10k times. Keep doing your long slow runs. Find an online pace calculator and project your HM time from you 5k and 10k pbs. If the 10k projection is materially slower than the 5k one then chances are you’ll want to aim for a slightly slower HM pace than the 10k suggests (short reason: you’re better over shorter distances and performance drops off disproportionally the further you go. Not at all unusual in novice distance running).
Then at your next HM stick to your chosen pace religiously. It will feel laughably easy to begin with. Less so in the final quarter. But if you finish with gas in the tank that is a much better outcome than blowing up before the finish.
Good luck, and stick with it!
Cheers - the 4.40/5.10 was literally for the first 1k only in all the excitement, it settled quickly into 5.30 to 5.40 - before the event I kept telling myself that 5.50 was probably the correct pace to try, but I felt so comfortable - probably like everyone else trying their first half marathon I'm sure.If you go out too fast in any endurance event it simply won’t matter how much you fuel - you will die a horrible slow death at some point before the finish. Been there, done that!
My advice: keep working on your 5k and 10k times. Keep doing your long slow runs. Find an online pace calculator and project your HM time from you 5k and 10k pbs. If the 10k projection is materially slower than the 5k one then chances are you’ll want to aim for a slightly slower HM pace than the 10k suggests (short reason: you’re better over shorter distances and performance drops off disproportionally the further you go. Not at all unusual in novice distance running).
Then at your next HM stick to your chosen pace religiously. It will feel laughably easy to begin with. Less so in the final quarter. But if you finish with gas in the tank that is a much better outcome than blowing up before the finish.
Good luck, and stick with it!
With the gels I just took one each half an hour, no real science behind that decision really.
It was fun mostly, and the crash whilst grim, was interesting to experience not having any input into my leg pace!!
MOBB said:
Muzzer79 said:
Did you taper before the event?
I would potentially have done more weekly miles than you, but it sounds like you were over-tired rather than anything else.
Could just have been a bad day.
Did you eat well the day before and on the morning of the event?
I ate well the day before, didnt eat very much on the morning other than a porridge bar as I dont tend to each before running.I would potentially have done more weekly miles than you, but it sounds like you were over-tired rather than anything else.
Could just have been a bad day.
Did you eat well the day before and on the morning of the event?
Tapering - I'm new to this but the week before I backed off the exercise generally, just a slowish 5k and I paced a 30 minute parkrun the day before.
The day before is for relaxing, sitting down, not moving much and storing the maximum amount of energy. Not going off and doing parkruns
Also, fuel before such an event is very important. If you don't tend to eat much, get up earlier and eat then.
Your body needs proper fuel, you cannot run for 2 hours on energy gels and a porridge bar.
Keep at it - this is all part of the learning experience of running for longer.
And don't give up on the full marathon! It's a great experience.
I wonder if this link will work;
https://www.strava.com/activities/7899218924
edit - my 4.40-5.10 must have been for the first 200m lol
https://www.strava.com/activities/7899218924
edit - my 4.40-5.10 must have been for the first 200m lol
Edited by MOBB on Monday 3rd October 11:10
Muzzer79 said:
MOBB said:
Muzzer79 said:
Did you taper before the event?
I would potentially have done more weekly miles than you, but it sounds like you were over-tired rather than anything else.
Could just have been a bad day.
Did you eat well the day before and on the morning of the event?
I ate well the day before, didnt eat very much on the morning other than a porridge bar as I dont tend to each before running.I would potentially have done more weekly miles than you, but it sounds like you were over-tired rather than anything else.
Could just have been a bad day.
Did you eat well the day before and on the morning of the event?
Tapering - I'm new to this but the week before I backed off the exercise generally, just a slowish 5k and I paced a 30 minute parkrun the day before.
The day before is for relaxing, sitting down, not moving much and storing the maximum amount of energy. Not going off and doing parkruns
Also, fuel before such an event is very important. If you don't tend to eat much, get up earlier and eat then.
Your body needs proper fuel, you cannot run for 2 hours on energy gels and a porridge bar.
Keep at it - this is all part of the learning experience of running for longer.
And don't give up on the full marathon! It's a great experience.
MOBB said:
Jesus Christ, you did a 20 mile bike ride on Wednesday aswell!Muzzer79 said:
MOBB said:
Jesus Christ, you did a 20 mile bike ride on Wednesday aswell!edit - 2x 20 miles, and I do push really hard on the e-bike.
Back to the Half Marathon drawing board!
MOBB said:
Cheers - the 4.40/5.10 was literally for the first 1k only in all the excitement, it settled quickly into 5.30 to 5.40 - before the event I kept telling myself that 5.50 was probably the correct pace to try, but I felt so comfortable - probably like everyone else trying their first half marathon I'm sure.
With the gels I just took one each half an hour, no real science behind that decision really.
It was fun mostly, and the crash whilst grim, was interesting to experience not having any input into my leg pace!!
In all honesty you probably don’t need any gels for a HM. They are more psychological for a two hour event than physiological. With the gels I just took one each half an hour, no real science behind that decision really.
It was fun mostly, and the crash whilst grim, was interesting to experience not having any input into my leg pace!!
Even a km at 4.40 can wreck your day if your target pace is 5.50. Think of your target pace like a bucket that’s being filled with water and that you’re trying to empty at the same time, whilst all the time keeping the water level as close to the top as the bucket as you can without it overflowing. You target pace is the best pace you can maintain for the full race distance.
If the rate of water in gets increased by 20% even for a short period, you’ll be working *very* hard to keep up, and that will quickly and adversely affect your ability to hold your maximal pace thereafter. It’s basically like trying to do your best performance whilst holding your breath for a chunk of it.
Mass start events are bloody awful if you have a pace that you want to hold. You need to concentrate so hard on your race and not let yourself get swept along by everyone else.
General tips :-
Aim to do the second half quicker than the first - ie. start slow.
Double the distance, then multiply time by 2.2 - ie. 25 min 5k ~ (25min x 2.2) 55min 10k
Carbo load in the 2-3 days beforehand - eat lots of carbs to pack muscle cells with max. glycogen.
No real exercise 2-3 days before event.
Aim to do the second half quicker than the first - ie. start slow.
Double the distance, then multiply time by 2.2 - ie. 25 min 5k ~ (25min x 2.2) 55min 10k
Carbo load in the 2-3 days beforehand - eat lots of carbs to pack muscle cells with max. glycogen.
No real exercise 2-3 days before event.
bigandclever said:
djglover said:
Why did I not perform as expected at an endurance event:
A: Not enough training
B: Over optimistic starting pace
C: Insufficient fuelling
D: A combination of the above
100% .. it’s not rocket surgery A: Not enough training
B: Over optimistic starting pace
C: Insufficient fuelling
D: A combination of the above
Tbh op your journey from 2016 to now, discussing the best strategy to approach the half marathon is amazing. Hope you don’t give up on it - there’s some good advice here.
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