Couch to 5K
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Are any C25Kers also doing the 5:2?

So with all the publicity surrounding the 5:2 after the Horizon documentary, I wondered if anyone here was also doing this diet and following the C25K plan at the same time? A lot of what Mosley discovered in the programme made a lot of sense and the results it can generate (lower cholesterol/IGF-1/blood sugar etc) are changes I would like to make to my own general health, but I worry about running on fast days. Presumably the most sensible thing would be to fast on rest days. Anyone got any first hand experience to share? .

19 Replies

I got to my goal weight a couple of weeks ago so its too late for me. But I have to say I don't think I could survive on 500 calories a day and run as well. I didn't see the programme but was part of a debate my friends were having 2 days ago, they all wanted to know how I had lost all my weight which was using and just by reducing fat and calories and eating more fruit & veg. I drink a lot more water than I ever used to too.


Hi oldgirl, well done for all your hard work

and determination.I to are doing the couch

to 5k and trying to watch what i eat. Could I

ask how much weight have

you lost? Ive lost a little about 8lbs i think.

I never weighed myself before starting my

runs, but ny clothes feel loose. I would love

to loose about 2 stone.


I was very interested in the horizon finding and need to do more reading, but my plan if I decide to do it is to ensure that the fast days are always on rest days and always in the week, as I think I could manage all day at work and just eat 600 calorie evening meal. But I don't think I could do it on a inning day or the weekend, whn I'm at home all day.

I asked someone on a blog the other day to let me know how they get on wih it in a couple of weeks time.


More interested in the health benefits, than weight loss, although I'll take the flat stomach if I have to..(3 stone of it)


Me too but most of my excess weight is belly weight which is the worst kind so if that disappears along with lowrr cholesterol/IGF-1 etc then bring it on. But am only fasting as you have suggested on weekday/rest days which means Monday and Wednesday for me.


I'm working on it but only started this week with the programme. I'm looking for weight loss primarily but if it is later proven to help humans with longevity and reduced risk of senility or Parkinson's then I'll take those benefits as a bonus.


Good luck and keep us posted on how you do :)


Yes, I'm doing this. I've had two fasting stints now and have lost 3 pounds. Not bad. It isn't interfering with my run (yet). I'm on week 5 run 3 (tomorrow). I've run on mornings after the second fast day, before breakfast. No problems with energy levels etc, but I don't think I'd run on an actual fast day, until I'm used to it. Once your metabolism adapts, though, it shouldn't be an issue.

I think this diet is really easy and there's an awful lot of scientific literature to back up the alternate day fasting on which it is based, if not much on the 5:2 diet itself. I think I'll be sticking with this diet (maybe even alternate day fasting).

While I was digging around, I think I found the paper from where it might originate:

The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women.

Harvie MN, Pegington M, Mattson MP, Frystyk J, Dillon B, Evans G, Cuzick J, Jebb SA, Martin B, Cutler RG, Son TG, Maudsley S, Carlson OD, Egan JM, Flyvbjerg A, Howell A.

Int J Obes (Lond). 2011 May;35(5):714-27. Epub 2010 Oct 5

Copy and paste that into google and you'll get a link to the paper, it's open access . The MP Mattson in the author list was the bloke with the mice on the Horizon programme. He's published a lot on fasting and calorie restriction.


Dont fad diet... I do slimming world which is just sensible eating to its core. Sensible eating for ever, not for the few months on a diet that results in you gaining as soon as you drop off.

I did c25K and SW, both since march this year and as of tonight i have lost 80 1/2 lbs (5st 10 1/2)


Hi Gazter,

You're right fad dieting isn't a good idea and you've done really well on a sensible eating diet.

I can only speak for myself but the Alternate Day Fasting is for me a permanent change which will give immediate benefits of weight loss but long term (read rest of my life) may also provide other benefits. I say "may" because the scientific evidence isn't yet conclusive in humans but the worse case scenario is that it's a healthier diet than I was on before.

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The reason I'm thinking of doing 5:2 is primarily the proposed health benefits and to see if it does actually work. Weight loss would be a benefit as well - particularly belly fat where my main issue is and it's teh most dangerous kind of body fat.

Congratulations Gazter on your incredible weight loss. But I know I couldn't stick to something like Slimming World, whereas eating 600 calories a day twice a week should be easy on my really busy work days. We'll see how it goes :)


Is there a book on this diet?


Dr Michelle Harvie is a dietician working in the field of breast cancer prevention in the Manchester nhs.She has developed a 2 days a week intermittent diet plan that is designed to be easy to follow. The information is available if you access their website and search for intermittent diet in their media area. I'm going to try it because it makes a lot of sense to me.


There are some details of the diet in the Daily Telegraph

Also an interesting article on exercise and weight loss


I was wondering wheher the two fast days are supposed to be concurrent, as that's what the good doc did? Or can you split them up during the week? Can you 'eat what you like' on non-fast days or was that only on the alternate day fasting? I found the whole programme made a lot of sense and it might be something I try, especially as the health benefits are so potentially huge. I think I used to do something very similar, though not intentionally, before I gained weight. Some days I just didn't feel hungry so I didn't eat, and my weight stayed contstant.


Don't remember what he did but eat stop eat a similar concept is not consecutive - so a tues and thurs or a mon wed fri what you need to avoid at all cost is the starvation responses which undermine the benefits


The fasting days should be none-consecutive. you can still eat what you want on the 'feeding' days. See the article and read the section entitles 'The 5:2 diet: what is it and how does it work?'


I'm going to give it a go with separate fast days so that they are not on my run days and are during the working week when I'm busy enough to not sit there craving food. There's no way I could do 2 days straight while working or just fast on the weekend when I'm sat around. That would be a sure fire way to send me rummaging for the jaffa cakes!!


I'll look forward to hearing how it goes. Fasting on run days (or running before eating after a fast day) doesn't sound like a good idea. I like the idea of alternate day fasting on rest days, but those are the days when it's hardest not to over-indulge. ;) I often find that I'm less hungry on my most active days.


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