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Half marathon with no training

262 replies

sunallsummer · 19/07/2026 00:42

Probably a stupid question sorry but I’m not a runner so have no idea!

DH impulsively signed up to do a half marathon in 2 weeks and has done zero training for it. He’s slim and has normal fitness I would say but definitely not a runner and previously did a 5km and completed it but struggled

I know it’s his choice and he’s an adult to it’s up to him, but I’m just a bit worried about the idea of him running 21km with little to no training. I’m just not sure if I’m just being overly anxious but it seems so far to my non runner brain! Having said that, I know people do 10km without any real training and it’s fine, has anyone ever done a half marathon without any training and did it go ok?!

My concern is when he puts his mind to something he can be very stubborn and competitive so I think when the run starts he’ll actually go much faster than he should and it’s not like he’ll accept he’s not trained and take it at a slower pace. His plan was to drink a few coffee and get some pre workout for it and frankly I’m worried he ends up unwell after it

If anyone who knows anything about running can put my mind at rest and reassure me that I’m being silly and dramatic and he’ll be fine (other than a normal amount of tiredness afterwards) I’d really appreciate it!

OP posts:
ThisSereneGoose · 19/07/2026 10:59

Lins77 · 19/07/2026 10:46

Please come back to let us know how it goes, I really want to know!!

Twisted ankle or twisted knee at mile 3.5, while he was ahead on time for his target, blaming the road condition and leaving with his head high because do you know how fast he would have finished without his injury 😂😂

Injury which will not require medical treatment obviously

ThisSereneGoose · 19/07/2026 10:56

Ginmonkeyagain · 19/07/2026 10:27

Heat is an issue as you can over heat and debydrate quickly, even at tempwratiess that are comfortable for walking.

Training is not just about getting faster, for distance running you need to learn how to take on water and electrolytes. I have seen experienced runners suffer badly from dehydration if it is hotter than expected or if they get their hydration wrong.

Mr Monkey ran Boston marathon a couple of years aho and it was an unseasonably warm day, more pertinently they used Gatorade which is more sugary than Europeans are used to and the on course water was in open cups, something he had not trained for.

He got round but was pretty sick (literally) at the end. Luckily I am an experienced marathon support team, so was there to meet him at the end with hydration tablets, water and salty crisps.

Its actually really dangerous to drink too much water

That's the mistake beginners make, they drink way too much water during the actual races.

You don't wait until the starting line to start drinking and you don't need to down 1liter of water because you are a bit sweaty.

SleepQuest33 · 19/07/2026 10:51

Im not a serious runner but DH is and based on what I’ve seen him do re training and planning ahead, I think yiur DH is delusional!

Was it a bet???? What on earth made him sign up?

LittlestBoho · 19/07/2026 10:50

This reminds me of that questionnaire where 50% of men thought they could win a fist fight with a grizzly bear. They don't live in the real world!

Please update us after the race OP

Lins77 · 19/07/2026 10:46

Please come back to let us know how it goes, I really want to know!!

Funnylass · 19/07/2026 10:42

GingerAndTheBiscuits · 19/07/2026 10:38

Has he been and bought brand new running shoes for the occasion as well OP? I’d suggest stocking your cupboards with blister plasters and ice packs for the aftermath…

He should definitely think about his shoes, and socks. If he has brand new running shoes he needs to practice with them beforehand. I like these socks to help prevent blisters https://www.ronhill.com/collections/hilly-twin-skin?srsltid=AfmBOorEV5vx4iv2LgLa0SeZqNqFPxxQX8E8bAJokLM4eu_lZdr7Nbs9

Twin Skin Running Socks | Hilly

Discover Hilly’s Twin Skin Running Socks, crafted for serious runners. Dual-layer design reduces friction, prevents blisters, ideal for long runs. Seamless toe construction ensures comfort. Strategic ventilation and cushioning offer support. Reflecting...

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hugasaurus · 19/07/2026 10:39

He’s delusional but he’ll discover that for himself!

GingerAndTheBiscuits · 19/07/2026 10:38

Has he been and bought brand new running shoes for the occasion as well OP? I’d suggest stocking your cupboards with blister plasters and ice packs for the aftermath…

Funnylass · 19/07/2026 10:37

I have run 3 HMs. My fastest 5k is about 32 mins and my fastest HM was 2:40. I ran this aged 38 and trained for about 3 months (2-3 runs a week including one long run, and cycling). I was already running 5k 3x a week before starting training. I’m quite overweight, so didn’t have a good base fitness. But I’m concerned his 5k time suggests he doesn’t have much base fitness either.

If his ego can cope with a bit of walking he will be fine. He is very unlikely to manage sub 2 and if he did manage there would be a higher risk of injury. I’d suggest he books a day off work the day after to recover and is open minded about his time, listen to his body on the day.

I’d ditch the coffee idea and stick to water/sports drinks and jelly babies, being able to chew/not choke can be surprisingly difficult if you don’t want to stop to eat so he should practice this. He should also be finding out how his stomach will react. For 13 miles with no experience he will probably want to fuel little and fairly often. Maybe every 5km. Stomach issues are very real for runners. After my 3rd HM I stupidly drank the smoothie thing they put in the goody bag at the end. It went literally right through me and I was stuck in a portaloo for the next hour unable to leave without shitting myself.

I’d suggest he attempts a very slow (ie much slower than his dreamed off race pace) 6 mile and 10 mile run, spaced out by several days, and ideally with at least a week left before the HM day. Then I’d do a couple of gentle 5ks the week leading up to the race.

Personally I wouldn’t run a HM in August at all, the heat is a real risk. Get excellent sun cream and plan for lots of hydration. Can he run with a bladder or similar? Again, little and often. A cap or visor too.

overall I actually think it’s just really lame and arrogant to try and run a HM with literally no training. He might be fine, he might even do well. But the work of a HM or marathon is the training. It’s putting in the miles, learning how to optimise your performance. Someone said to me the race is just the victory lap and I agree. The achievement includes everything that leads up to the day.

ShortColdandGrey · 19/07/2026 10:33

I did a half marathon last Sunday and there were a few men like your husband. Hopefully he can finish in the time frame and doesn't end up injured like they did. Make sure he warms up his hips before he starts and all he gets is sore feet and legs. I did run past a guy last Sunday who had shooting pains up his thighs at the halfway mark. He told his mate he would rather be injured than not finish.

SmashThePatriarchy · 19/07/2026 10:30

Just let him realise himself that he’s stupid!

BringBackCatsEyes · 19/07/2026 10:29

ThisSereneGoose · 19/07/2026 10:12

Normally fit people can walk a half marathon no problem, even if a bit of a boring walk, so if he gets too tired he'll just walk 😂

What's more likely to happen is injuring himself and being unable to do any running any time until he properly heal.

Might be worth booking a physio before and after.

Under 2 hours? No chance, but he can blame the wind. Saying that coffee will make him run faster is stupid, where did he get that from?

Edited

It's worth checking if there is a time cut off. Road closures may end (if it's a big HM with road closures that is) and marshals will stand down.
It's likely to be a smaller HM if he managed to get a place just 2 weeks before the event.
People can still complete the event after a time cut off on the understanding there are no marshals, but (as we all keep saying)...what's the point?

Beachbeach · 19/07/2026 10:29

he can walk it! He won’t be doing sub 2 on no training.

BauhausOfEliott · 19/07/2026 10:27

Savoretti · 19/07/2026 08:18

How old is he?
My brothers used to run marathons in their 20s and 30s. They played a bit of squash and football sometimes so fit ish but not runners. They managed just fine. Young bodies, strong impulsive heads. He will be fine if he is determined 💪

Footballers can run several miles during the course of one 90 minutes. Even defenders cover around 5 miles and a midfielder can cover 8 or 9. They’re doing it in short sprints, but that’s actually more challenging than a steady jog - a football match is basically a 90-minute HIIT workout.

The OP’s husband has previously struggled to jog 3 miles. He’a not as fit as a bloke in his 20s who plays football and squash and he’s not going to perform well running 13 miles. He’s going to end up walking most of it.

Ginmonkeyagain · 19/07/2026 10:27

Heat is an issue as you can over heat and debydrate quickly, even at tempwratiess that are comfortable for walking.

Training is not just about getting faster, for distance running you need to learn how to take on water and electrolytes. I have seen experienced runners suffer badly from dehydration if it is hotter than expected or if they get their hydration wrong.

Mr Monkey ran Boston marathon a couple of years aho and it was an unseasonably warm day, more pertinently they used Gatorade which is more sugary than Europeans are used to and the on course water was in open cups, something he had not trained for.

He got round but was pretty sick (literally) at the end. Luckily I am an experienced marathon support team, so was there to meet him at the end with hydration tablets, water and salty crisps.

ThisSereneGoose · 19/07/2026 10:12

Normally fit people can walk a half marathon no problem, even if a bit of a boring walk, so if he gets too tired he'll just walk 😂

What's more likely to happen is injuring himself and being unable to do any running any time until he properly heal.

Might be worth booking a physio before and after.

Under 2 hours? No chance, but he can blame the wind. Saying that coffee will make him run faster is stupid, where did he get that from?

BringBackCatsEyes · 19/07/2026 10:09

Jackiepumpkinhead · 19/07/2026 10:04

He’s not going to die! He’s an arrogant fool who will deserve his blisters.

Not dying is quite a low bar if you care about someone’s welfare. Yes he’s a fool, but it’s not the worst trait to have in a partner.

FMLpassthegin · 19/07/2026 10:06

The baffling question is why do it on no training? If he wants to run a half and wants a sub two hours why not enter in six months time and train for it and reduce the injury risk and learn how to fuel for it properly and how to pace it? What on earth is the point? If it’s just to say you’ve done it you may as well walk it. There is no way he will do it sub two hours. You don’t times your 5km by four - and think you’ll get faster you get SLOWER as fatigue sets in! You base a marathon pace on your half marathon time and double it and then add some time on - ie another 10 /15 mins. He’ll be lucky to do it in 2hr 30 and even then he will finish feeling broken and bloody stiff for the days that follow.

Ace56 · 19/07/2026 10:05

Will he finish it? Yes
Will he run the whole way? No
Will he do it in under 2 hours? Absolutely not

Jackiepumpkinhead · 19/07/2026 10:04

BringBackCatsEyes · 19/07/2026 10:03

Because she cares about the great buffoon!

He’s not going to die! He’s an arrogant fool who will deserve his blisters.

pragmatismuniversalsentimentalist · 19/07/2026 10:04

Ginmonkeyagain · 19/07/2026 08:15

Also are you in the UK? A half marathon at the end of July does not sound wise. There is a reason why most mass participation distance races take place in spring and autumn here. Running in the heat with no experience is a recipe for disaster.

Mr Monkey ran a half in mid September a couple of years ago. There was an unseasonal heatwave - 30 degrees). He got round ok as he is experienced in running in the heat but he said people were dropping like flies on tne course.

I was going to ask this OP, where on earth are you that has scheduled a summer half marathon?! They are usually march /april or October time, and for a reason!

I mean frankly he just sounds like a massive dickhead doesn't he, arrogantly reckoning he can pull off a sub-2hr half with no training. What a bellend.
Former regular runner here and most women training for a first half marathon are aiming for 9.5 - 10 minute miles over the distance giving a time somewhere between 2hr 10 and 2hr 20. Blokes training for a first half are usually aiming to go under 2hrs but that is usually with 6-9 months build up increasing their distance by 10% each week and allowing for a taper towards the end.

There is a massive massive difference between running a 2hr half (and you'd not get that time if doing big stints of walking) and doing it in 3.5hrs doing loads of chunks of walking in there.

BringBackCatsEyes · 19/07/2026 10:03

Jackiepumpkinhead · 19/07/2026 10:01

Why do you need to be reassured? He’s an idiot and will struggle, let it be a life lesson for him.

Because she cares about the great buffoon!

lessglittermoremud · 19/07/2026 10:02

I would mention it’s a terrible idea to load up on coffee but otherwise let him crack on. If he’s as stubborn as you say then he’ll not listen anyway.
To put your mind at rest my 11 year old did a 10 mile walking challenge a couple of weeks ago in hot weather. I was hoping it would be cancelled but because of the early start it they got to the checkpoints on time then they would be back before the worst heat of the day.
He easily completed it at a fast walk and was one of the first teams back, I would say he has probably the typical fitness levels of a child of his age that plays a team sport.
If your DH sets off at too fast pace he will slow to a more sensible one or have to drop out, hopefully he’ll stick at a sensible jog, walk a bit if he’s struggling and be able to finish!

Jackiepumpkinhead · 19/07/2026 10:01

Why do you need to be reassured? He’s an idiot and will struggle, let it be a life lesson for him.

redstaff · 19/07/2026 09:59

sunallsummer · 19/07/2026 00:42

Probably a stupid question sorry but I’m not a runner so have no idea!

DH impulsively signed up to do a half marathon in 2 weeks and has done zero training for it. He’s slim and has normal fitness I would say but definitely not a runner and previously did a 5km and completed it but struggled

I know it’s his choice and he’s an adult to it’s up to him, but I’m just a bit worried about the idea of him running 21km with little to no training. I’m just not sure if I’m just being overly anxious but it seems so far to my non runner brain! Having said that, I know people do 10km without any real training and it’s fine, has anyone ever done a half marathon without any training and did it go ok?!

My concern is when he puts his mind to something he can be very stubborn and competitive so I think when the run starts he’ll actually go much faster than he should and it’s not like he’ll accept he’s not trained and take it at a slower pace. His plan was to drink a few coffee and get some pre workout for it and frankly I’m worried he ends up unwell after it

If anyone who knows anything about running can put my mind at rest and reassure me that I’m being silly and dramatic and he’ll be fine (other than a normal amount of tiredness afterwards) I’d really appreciate it!

I did a half marathon with no training. I could run approx 5k at the time.
Honestly - the biggest part is the mental battle, I went into it with just wanting to enjoy myself and I did exactly that. When things felt hard, I slowed and walked. I think as your DH already has a steady fitness level, he’ll be fine. He may lose some toenails though.

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