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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:
Merkins · 02/08/2026 17:52

It must be over by now.

Youspurnme · 02/08/2026 13:05

Checking in to see how he managed 😂

Merkins · 01/08/2026 18:18

BringBackCatsEyes · 01/08/2026 17:16

A Sunday half marathon is far more common than a Saturday one, so I bet it’s tomorrow.

Good point!

BringBackCatsEyes · 01/08/2026 17:16

A Sunday half marathon is far more common than a Saturday one, so I bet it’s tomorrow.

Merkins · 01/08/2026 16:50

I can’t be the only one dying to know how it went. Please come back and tell us OP!

Tinkerbellflowers · 24/07/2026 08:02

I think there is another week yet. But would love to know how his training is going.

Scarydinosaurs · 24/07/2026 05:14

How did he get on??

BringBackCatsEyes · 20/07/2026 14:48

BarnacleBeasley · 20/07/2026 14:38

Yes, it's way faster than I ever managed! You can see the UK rankings on powerof10.uk for different distances and years (click on the road & distance tab). They record rankings for women up to 1:40 and men up to 80 mins for half marathon.

Cool. Yeah..I was very good (not that good!)....10 years ago. Clinging on with fingernails at the moment.

BarnacleBeasley · 20/07/2026 14:38

BringBackCatsEyes · 20/07/2026 13:50

Are you sure it's as many as 53 women running sub 1hr 15? That's really very fast!

Yes, it's way faster than I ever managed! You can see the UK rankings on powerof10.uk for different distances and years (click on the road & distance tab). They record rankings for women up to 1:40 and men up to 80 mins for half marathon.

BringBackCatsEyes · 20/07/2026 13:50

BarnacleBeasley · 20/07/2026 13:19

Maybe, and I'm sure some of them were lying. Others would be the ones who'd have the aptitude to run significantly faster if they trained (more than 1300 men ran sub 75 min half marathons in the UK last year vs 53 women). I don't think we actually disagree anyway - I agree it's a minority, but probably a bigger minority than it would be for women. Either way, it's not really relevant here as OP's DH is definitely not one of them.

Are you sure it's as many as 53 women running sub 1hr 15? That's really very fast!

BarnacleBeasley · 20/07/2026 13:19

MrsOni · 20/07/2026 13:04

Someone with a good level of fitness could get round a half, but anyone who tells you that they can hold that pace for that long without specific running training is in the minority and/or lying. Which is something men do quite often.

Maybe, and I'm sure some of them were lying. Others would be the ones who'd have the aptitude to run significantly faster if they trained (more than 1300 men ran sub 75 min half marathons in the UK last year vs 53 women). I don't think we actually disagree anyway - I agree it's a minority, but probably a bigger minority than it would be for women. Either way, it's not really relevant here as OP's DH is definitely not one of them.

Triskellion75 · 20/07/2026 13:13

Ooooft I think he's in for a bit of a shock. I've done two HMs with proper training and I find the idea that you can just rock up and complete one with on zero training and fuelled by coffee both amusing and irritating.

MrsOni · 20/07/2026 13:04

BarnacleBeasley · 20/07/2026 12:57

I didn't say 'most men' or anything like that, I said 'plenty of men', and it's true. Mostly the youngish ones who play football or similar fairly regularly but haven't really done much running. When I was actively training with a local club and participating in running forums you'd come across them fairly regularly as they'd have done a half marathon for a laugh with no training, then couldn't understand why it was so hard for them to then train to get under 1:45 or 1:30 or whatever their next round-number goal was. Mostly they would get frustrated and give up (or keep going but never really listen to advice on how to train better) but some persevered and got quite good.

Someone with a good level of fitness could get round a half, but anyone who tells you that they can hold that pace for that long without specific running training is in the minority and/or lying. Which is something men do quite often.

BarnacleBeasley · 20/07/2026 12:57

MrsOni · 20/07/2026 12:36

There really, really isn't plenty of men who could run a sub 2 hour half without training.

Someone without a decent amount of fitness cannot sustain 9 min mile pace for that long.

Edited

I didn't say 'most men' or anything like that, I said 'plenty of men', and it's true. Mostly the youngish ones who play football or similar fairly regularly but haven't really done much running. When I was actively training with a local club and participating in running forums you'd come across them fairly regularly as they'd have done a half marathon for a laugh with no training, then couldn't understand why it was so hard for them to then train to get under 1:45 or 1:30 or whatever their next round-number goal was. Mostly they would get frustrated and give up (or keep going but never really listen to advice on how to train better) but some persevered and got quite good.

Keepoffmyartichokes · 20/07/2026 12:52

MrsOni · 20/07/2026 12:36

There really, really isn't plenty of men who could run a sub 2 hour half without training.

Someone without a decent amount of fitness cannot sustain 9 min mile pace for that long.

Edited

Agree with this, I think a few people think of someone can do a 10k in just under and hour then they can do a half in 2 but it's not as simple as that. They don't account for the fatigue and the mental toll on running at a fairly decent pace for that long. My DH can easily smash out a 50 minute 10k but there is no way he would be able to do a half marathon at that pace or any pace without training. He would have to walk some.

MrsOni · 20/07/2026 12:36

BarnacleBeasley · 20/07/2026 12:17

I am a runner (albeit lapsed) and I would say that - annoyingly - it's much easier for men, and there are plenty of men who could run a sub 2-hour half marathon with no training. However, as OP's DH can't run a sub-30-min 5k, he is clearly not one of them. He will start too near the front, set off too fast, and then end up walking most of it. But it sounds like he won't be a dick about it afterwards. He's very unlikely to do himself any lasting damage.

There really, really isn't plenty of men who could run a sub 2 hour half without training.

Someone without a decent amount of fitness cannot sustain 9 min mile pace for that long.

BarnacleBeasley · 20/07/2026 12:17

I am a runner (albeit lapsed) and I would say that - annoyingly - it's much easier for men, and there are plenty of men who could run a sub 2-hour half marathon with no training. However, as OP's DH can't run a sub-30-min 5k, he is clearly not one of them. He will start too near the front, set off too fast, and then end up walking most of it. But it sounds like he won't be a dick about it afterwards. He's very unlikely to do himself any lasting damage.

Lins77 · 20/07/2026 12:07

JohnnyMcGrathSaysFuckOff · 20/07/2026 12:00

The idea that a 2h HM is "quite a slow jog" 🤣 I'm guessing that poster is Mo Farah!

Like I said, I am gym fit by most people's standards, and have recently started easing back into running.

I did a HM distance on one of those really hot days about 10d ago, keeping a very steady pace so as not to overheat, and got just over 2h 20m which I thought was fine for a starter time.

The idea you can break 2h with slow jogging and walking is just for the birds

It was a "very slow jog" according to them!

JohnnyMcGrathSaysFuckOff · 20/07/2026 12:00

The idea that a 2h HM is "quite a slow jog" 🤣 I'm guessing that poster is Mo Farah!

Like I said, I am gym fit by most people's standards, and have recently started easing back into running.

I did a HM distance on one of those really hot days about 10d ago, keeping a very steady pace so as not to overheat, and got just over 2h 20m which I thought was fine for a starter time.

The idea you can break 2h with slow jogging and walking is just for the birds

ItsOkItsDarkChocolate · 20/07/2026 11:58

His legs will probably hurt for a few days. You may want to go away somewhere! 😂

Is he entering MLC territory? 😉

TreeDudette · 20/07/2026 11:18

My husband is a runner and does a 5km Park Run every weekend and often also runs once or twice a week with running club between 5 and 10km. He does 4 or 5 x 10km races per year and does 5km in about 30mins, 10km in about an hour. Last year he did his first half marathon and was really hoping for under 2hours. He trained intermittently (life gets in the way) for is for 4 months beforehand. He completed it in 2hrs 10min so was very disappointed but he ran the whole way at a steady pace (Pacing is something he has really been working on). It was hillier and harder than he'd bargained for.

I think unless you are under-stating your husbands fitness he will go off far too fast, run out of puff about half way around and either drop out or end up walking / dragging to the finish. It won't kill him but it might make him feel pretty unwell in this heat.

Fizbosshoes · 20/07/2026 11:12

DeterminedRat · 19/07/2026 23:58

I think that with the popularity of marathons these days people forget that it's actually really far. Even running 10km is running far. Running that again and a bit is really fucking far. It's not something someone with no fitness background can slow jog.

I've been running for 2 years now and 5:40/km is my 'easy pace' now for long runs but that's with 1000s of kms and a lot of work behind me.

If it's hot he really needs to stay on top of his hydration and electrolytes though and listen to his body. A half marathon isn't a fun run for beginners and the distance should be respected.

Im sometimes surprised at runners (who havent run previously) finishing the London marathon in eg 10 hours and saying they underestimated how hard it would be....and as a regular runner who has run 9 marathons and lots of halfs im confused why they thought it it wouldnt be really hard!! Thats why I dont do one every year because I know how tough the training is, and the race itself, can be. (Although I've suppose if you miss out the training you've taken some of the hard parts out...? 🤣)

I actually quite enjoy training for a half

Havanananana · 20/07/2026 10:57

Newname26 · 19/07/2026 09:34

Whats the worse thing that could happen? Sore feet and take longer than planned?

Dehydration, electrolyte imbalance and fatigue - with the risk of confusion, dizziness, headaches, blood pressure and heart issues, plus the risk of subsequent injuries (e.g. dizziness causing a fall that results in a head or limb injury).
Heatstroke or hyperthermia - a real risk on hot, sunny days.
Impact injuries to feet, ankles, knees and hips and muscle injuries - particularly if the course is all on tarmac or hard surfaces, exacerbated by unsuitable footwear and poor running technique.
Friction injuries - foot blisters, nipple chafing and other chafing damage caused by unsuitable clothes.

All of these are possible, and the risk is higher for anyone who has not trained or who has an unreaslistic opinion of their own abilities. Most will result in short-term discomfort, but a foot full of blisters can take weeks to heal and muscle or knee injuries can take far longer.

hugasaurus · 20/07/2026 10:14

A slow jog is probably round about the 7 min a km pace for a man who doesn’t run, and if he was able to maintain that for an entire HM, which I doubt, it would take 2.5 hours if he held that pace solidly. If you start adding walking in, he’ll be nearer 3 hours. That is without the actual physical impact of running on joints and muscles that aren’t used to it for that length of time, cardiovascular stress, etc. Holding a pace for 30 mins and 2 hours and 30 mins are very different beasts!

I think thanks to Insta running content and stuff people have become a bit desensitised to how long these distances actually are and how long it takes to work up to them if you do actually intend to run them. Nothing wrong with walking them if that’s what you want.

That said, I doubt anything really bad will happen to him. He might end up with an injury, he’ll most likely do a combo of jogging and walking, feel pretty wretched, stumble across the line around 2.5-3 hours and be very sore the next day.

Lins77 · 20/07/2026 10:07

hugasaurus · 20/07/2026 10:01

Yes that is actually a decent pace. That’s my goal HM pace for six months’ time and I run 4 times a week, have done multiple 10k races, can do well under a 30-min 5k. Two hours would be an v impressive time for most amateur runners for their first HM, and I mean runners who have actually trained for it!

Agree, I've never managed a sub 2 HM, and my 5k PB is 24 minutes.

I was at my fittest when ultra training, and I might have managed it then, but definitely wouldn't now. Maybe one day if I really put the work in.

Good luck with your race!

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