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Couch to 5K
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Why am I suddenly struggling with C25K?

So I've managed to do Weeks 1 - 6 no problemo, and am actually really starting to like running. I inadvertently managed to sign up to a half marathon in April which is why I started.

I've had some pain in my shins since about week 2 that I've put down to shin splints and hoping it clears up on its own. (its not that bad)

However today I attempted Week 7 Day 1. 5 minutes in I was so done. Laura helpfully was like "you should be getting into a good pace now, keep going!" But I literally couldn't go any further. I was all achey, my breathing was already like I'd done 20 minutes and I had like no energy whatsoever. In the previous 25 minute run I was like a bit tired by 10 minutes, able to continue to 20 minutes then push myself to run really fast for the last 5 minutes.

I usually run after 5pm, but today I went around lunch time (I hadn't had lunch first, I know not to run for at least two hours after eating.) I also tried a different route just to mix things up, but that doesn't seem to have gone down well.

I'm going to retry on my normal route and normal running slot tomorrow, but in the mean time any ideas on what caused today's disaster?

15 Replies

Half marathon! That's way ambitious and I think unrealistic to be honest. It's the recipe for injury. If you are already feeling shin splints then I would forget the idea and concentrate on c25k and then slowly and carefully progressing whilst working on your overall strength and fitness.

Having said that I suppose you could tackle it by run/walking it

Your run yesterday could have been pants for various reasons but it happens. Just make sure you are adequately fed, watered and rested. Also slow things right down, don't worry about speed ☺


There is not necessarily a specific reason. It can be what you've eaten, how much sleep you got, whether you are sickening for something etc etc. We all have them!

Don't panic! Slow things down and try again - it'll probably be fine next time.

And, by the way, I agree with MissW that a half marathon in April feels overly ambitious. Do you need to take a bit of pressure off yourself? Over training can risk injury and can kill the joy.

Do take care.


You had what we seasoned veterans call 'a bad run'. Don't worry. Happens to us all. even when you can run for 5 hours at a stretch there will still be days when, for no obvious reason, you punk out after 5 minutes.

Have a day off, run again.

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Do you have asthma or breathing problems? I really struggle for breath in the wet and cold and am finding the freezing, driving rain a real pain for getting the air in my lungs.

Of course, it might be that you thought at week one that by now that running would be easy- I did anyway, and I have never found that to be the case, and as Rignold pointed out, sometimes you just have a bad run.

As for the aching shins, some more calf stretching and possibly foam rolling and step drop things (I'm sorry I can't rember their name!) might help get rid of the niggles.

I hope it was nothing more than a bad run, let us know how you get on next time- try not to be too hard on yourself! :-) you've already come so far from week 1!

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Forget about half marathon for now, just concentrate on c25k and slow down!


Definitely concentrate on c25k at the moment. Sounds like you may be trying to go too fast. To reiterate what many a better runner than me has said, go as slow as you think possible and then slow down a bit more. At this stage in the programme speed is completely immaterial, it's all about getting through the runs. Good luck, Emma. Chalk it up to experience and try, try, try again :)


Bad runs can be due to many reasons. I agree with what others have written especially Ullyrunner.

It can be due to number of factors:

1. Bad night's sleep

2. Underhydration

3. Shoes unsuitable for your gait (you may need gait analysis which is free at many running shops)

4. What and how much and when you last ate

5. Think of reducing speed further if that helps

6. What is going through your head?

There are compression socks that can help with shin splints too. So can a visit to a physio therapist.

Next, the half marathon. 13.1 miles or 21K is a long distance. However, it is just a number of steps. And if that is your goal, you need a plan to go with it.

A simple plan works best.

I use an app called GymBoss (not the actual device) which I now program for 1 minute intervals - about 4 hours worth for a half marathon.

And every minute on minute, I device whether I will run or walk the next minute depending on how I am feeling.

Plus, I run every downward slope.

Now, that is my plan. And it has served me well so far.

You can make your own and see what works for you for that distance.

Apart from running, you will need other preparation for a Half Marathon:

1. Layers depending upon typical weather at that time of the year

2. Shoes and Socks - good moisture wicking socks

3. Hydration - how do you plan to keep yourself hydrated?

4. I use something called Clif Shot Blocks to eat one every 2 miles or so. They provide some sustainance.

5. Squats and cross-training along with some hill walking - prepare those legs and strengthen those muscles

People in the front run the entire event. Then there are run/walkers. And finally there are the walkers. Most important people are those who finish the event and not at a certain pace.

If you have gone beyond W5R3, you can definitely run/walk a half marathon.

Good luck! You can do it!




Thank you so much! That's really helpful - I'll be sure to take all your advice on board. I'm thinking its in April so its manageable. I'll be sure to look into new trainers and socks.

I love mountain walking so I'll be sure to up that as well. I'm thinking slow and steady around the 13 miles, and there's hydration stations every two miles from memory.

A lot of the training programmes need at least a 5k running base and can get you running in 12 weeks ish. I think I've got plenty of time, its my first one, my only goal is just to cross the line - I don't care about the time! :)

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Good luck!

I would recommend picking up a bottle of water at every hydration station even if you feel you don't need it.

Better to have and not need than to need and not have :-)

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"Inadvertently" :)

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Haha yes, I emailed this charity asking what sort of support they gave like advice and running shirts then got an email back like "we've got you signed up for a half marathon in April" and my reaction was like "what." So now I'm doing a half marathon :D


AHhh you guys are all amazing! Thank you so much for all your support.

I've just done week 7 run 1 (yeeeees!) and managed to cover about 3K in the 25 minutes which I think for me is rather brilliant. I did stupidly run too fast in the first half and kinda knacker myself for the second, so next time should hopefully go better.

I think it was probably just a bad run, but I've put it down to experience and over come that and finished today :D

I'm really tempted also to go back and do one of the runs from weeks 2 or 3 just to show myself how far I've come (just because, its sounds stupid, but in my head I've not actually improved) - is this a good idea? To give me something to like compare it too.

With regards to the half marathon, its actually keeping me quite focused on running, like the number of times I've gone for a run because I know I have a goal to work towards has actually been quite useful. I know it does kind of put some pressure on, but I find I work better under pressure. As I think I mentioned before, for me that half marathon will just be about raising money for a brilliant cause and getting across the line, I don't really care about the time (well fast enough not to be caught by the bus that goes around picking up the people who go too slow).

Thanks again guys!


Perhaps you're coming down with something, last week I had two rotten runs, the first I had no energy or inspiration and my pacing was all over the place. The second was ok but I felt heavy. Woke up the next day with a cold which had evidently been brewing...it's a horrible one too, not run for over a week...

If you feel ok now just put it behind you, as Laura says some runs will feel better than others, there's no rhyme or reason for it.


That's what it turned out to be! I wasn't feeling too peaky at the end of the week so took a break and gone back out today and had a fantastic run :D

Just the way of life I guess...

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Yay! I can't wait to get back out there, have another fantastic run for me please xxx


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