Will I hurt myself doing 13.1 without training

Go to youtube, search for ‘untrained marathon’ or ‘marathon untrained’. You should get a good feel for what happens.

IMO it’s asking for an injury.

Just for interest’s sake: this guy did a DIY Ironman with no specific training at all. He was pretty athletic and young, so not exactly couch to Ironman, but still.

I’m not sure how old you are. The older you are, the higher the chances of an injury. Also, don’t forget that there are many ways to do a half marathon, and run some walk some is acceptable. Presumably the harder you push yourself, the higher the chances of some injury beyond just DOMS.

And last, do you actually want to do this? In economics, there’s a concept called the sunk cost fallacy. Basically, you shouldn’t do something just because of sunk costs. You should base your decision on what lies ahead. In this context, do you actually want to do a half marathon? Would you actually get pleasure from it?


Just another “Don’t do it” vote. Not worth it. I love that “sunken cost fallacy” is covered above! As a runner and cyclist, I’ve done several 13.1’s. There’s a lot that can go wrong during a half. You may feel good for the first 3 or 5 miles, but the remaining 10 or 8 are still really long. The fact that you haven’t enjoyed running in the past, have not been running at all, and have some really cool and important “A-races” ahead this year are all good reasons to not run the 13.1!

From one ‘exerciser’ to another, skip it, avoid the injury, and do the ‘exercise’ you enjoy most! Lol

Introduce your wife to the concept of sunk costs. The entry fee is gone, no matter what. Seems like you’d incur significant additional costs if you run. Especially since you’ve stated you’ve never really enjoyed it, why bother? I’d email the race director and offer to donate the slot to someone else or your entry fee to the organizers. Races have been hit hard by the pandemic, they’ll appreciate it.

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Years ago one of my classmates (medical school) decided to run a marathon without any training. He finished, but took over a month to recover, could barely walk at first. Honestly, I wouldn’t advise it.

Recommendation: Give it away to someone else. Unless it is something you WANT to do, I don’t think you have anything to gain.

Personal anecdote: On a whim signed up for a 50 miler with three weeks time to train. But I did have a long running history and have done multiple 50k’s. I had just stopped running a couple years before because I got so involved in MTB riding. I ran the 50 miles, rode my bike the next day.

I think the worst case is you become a triathlete.


Well, you’ll be sore for sure. At 27 and if you’re otherwise active I think if you go slow you’ll otherwise be fine in a week. But it probably won’t be enjoyable based on your description of things.

Lol, very good.



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I did pretty much this exact thing when I was 27; ran a half marathon when the only run I had done for months prior was a 4 mile run on Wednesday (I still had doms from that on the start line). It ended up being my second fastest half; arguably faster if you adjust for elevation.

That said, my quads & IT bands were screaming at me for the better part of a week after. In your situation with Leadville I probably wouldn’t have done it. Also, I had previously been a reasonably competitive triathlete a few years earlier so I probably had some longer term physical adaptions from that (technique, at least).