How compatible is 'Fasting' (5:2 etc) with running?

Spirogyra

It causes the body to regenerate and repair. But if one is running a lot,Doe's one need good quality meals in the morning etc ? I've tried skipping the odd breakfast but only on a few days occasions. Is 16 hours the minimum effectively fast does anyone know? And has anyone integrated it into a 'running lifestyle'? Thanks S

RayCun

What is the advantage of fasting over a good daily diet?

jamule

RayCun wrote: »

What is the advantage of fasting over a good daily diet?

more than likely none. Put it up there on the shelf with barefoot running and any other dietry fad

Murph_D

Hardly any research done, and thus no evidence that fasting works.

tunguska

Spirogyra wrote: »

It causes the body to regenerate and repair. But if one is running a lot,Doe's one need good quality meals in the morning etc ? I've tried skipping the odd breakfast but only on a few days occasions. Is 16 hours the minimum effectively fast does anyone know? And has anyone integrated it into a 'running lifestyle'? Thanks S

Didnt do 5:2 or any of that but did fasted long runs. Only easy pace stuff though. Tried doing a fasted track session and fell apart after half a mile. But the fasting for easy paced long runs works like gang busters. Only caution is theres evidence to support kidney damage could result from ketones. But i believe thats kind of like atkins type of low carb fasting. But all the same i wouldnt do it long term. Just use it for a marathon training cycle and then return to normal.

ooter

Wouldn't know a hell of a lot about it personally but there's a lad called Barry Murray that I've listened to in a few interviews/podcasts and he talks about it as a good way to promote a fat burning state but he recommends you only run fasted 2 days a week max.
Did it myself a couple of years ago when training for DCM, ran all my weekend long runs on empty and I definitely think it helped as I got my PB that still stands.

Atlantic Dawn

It would be idiotic.

TFBubendorfer

A friend of mine did that a few years ago and it works very well for easy runs but workouts in a fasted state are out of the question.

He lost a ton of weight during that time, which was his main aim, and he feels it helped his running - at least as far as running ultras was concerned.

Enduro

Spirogyra wrote: »

It causes the body to regenerate and repair. But if one is running a lot,Doe's one need good quality meals in the morning etc ? I've tried skipping the odd breakfast but only on a few days occasions. Is 16 hours the minimum effectively fast does anyone know? And has anyone integrated it into a 'running lifestyle'? Thanks S

I've been on the "skipping breakfast" intermittant fasting style for a little bit now. I found that relatively easy to undertake and incorporate into lifesyle. (I reckon I'd find 5:2 more difficult to adopt personally, but each to their own) I haven't noticed any negative issues with my training or racing.

As background, I would have been doing all my training runs on empty for years now, with a particular emphasis on BtoB long runs at the weekend. That's all aimed at helping trigger fat-adapated running. Removing breakfast was a relatively small addtional step.

I wouldn't be surprised if people had energy issues on training sessions for a couple of weeks if they do adopt an I.F. eating pattern, but I would guess once your body adapts you'll be back to normal.

That all works fine for ultr training. I would imagine that icorporating I.F. into one's lifestyle for shorter distance racing would probably be just as straighforward. Getting the meal timings right would probably address any potential issues.

Enduro

RayCun wrote: »

What is the advantage of fasting over a good daily diet?

It isn't to do with diet, its to do with timing. Subtly different.

This is as good a site as any to read up on the ideas behind it. Lots of links to other articles and to scientific papers. There's a BBC horizon episode about I.F. here

average_runner

So this is basically another fad that will die out like the rest of them.

seamus

average_runner wrote: »

So this is basically another fad that will die out like the rest of them.

It's just another form of calorie restriction. Rather than having to find a 4000 kcal deficit over 7 days, they just front-load the deficit into the first two days.

There are as usual people claiming feeling energised and all sorts of other effects, but aside from some small positive results in rat trials, no benefit proven for humans over any other calorie restriction.

HelenAnne

)

TFBubendorfer wrote: »

A friend of mine did that a few years ago and it works very well for easy runs but workouts in a fasted state are out of the question.

He lost a ton of weight during that time, which was his main aim, and he feels it helped his running - at least as far as running ultras was concerned.

I always do my Sunday LSRs fasted (due to laziness re breakfast as mentioned before on the forum not for any fat burning plan or anything). Sadly, I never seem to lose any weight! Do the runs have to be a over a certain length or several times a week for the fasting to have amazing weight loss properties, or maybe I'm eating too much after the runs? (sorry to fixate on the weight loss side of it, but it would be nice if something I'm already doing could be tweaked for miraculous weight loss

Enduro

average_runner wrote: »

So this is basically another fad that will die out like the rest of them.

One of the things I love about discussing running nutrition is that you can be completely open with your competitors about what works, but people are so unquestionaly wedded to orthodoxy that they just won't listen. It's hilarious.

Krusty_Clown

The 5:2 diet isn't about running fasted. It's a starvation diet, concerned with restricting your total calorie intake for two days per week to 25% of normal calorie intake. That's about 500-600 calories for most people (or a bowl of porridge and an apple, if you want to equate it to food). I'm pretty sure that those of you who run fasted will eat a normal diet afterwards, but in this scenario your calorie intake after your run is also restricted, if you happen to run on the '2' days (or the day after). I'm also sure there are outliers/multi-day eventers, where getting used to restricted calorie intakes probably makes sense (like where you have to carry your food), but for most people, a starvation diet is not compatible with running.

Spirogyra: If the goal is weight loss, then either do your starvation diet or run. Don't do both. If the goal is to be a better runner, then run and skip the 5:2 diet (and run fasted, if that makes you feel better).

seamus

HelenAnne wrote: »

)

I always do my Sunday LSRs fasted (due to laziness re breakfast as mentioned before on the forum not for any fat burning plan or anything). Sadly, I never seem to lose any weight! Do the runs have to be a over a certain length or several times a week for the fasting to have amazing weight loss properties, or maybe I'm eating too much after the runs? (sorry to fixate on the weight loss side of it, but it would be nice if something I'm already doing could be tweaked for miraculous weight loss

Calorie restriction is the basis behind the "magical weight loss" touted by these kinds of diets.

Your body stores a certain amount of energy in muscles and liver as glycogen. This is how it maintains a smooth level of energy in the blood, even when you haven't eaten in a couple of hours. It's the body's version of the uninterruptible power supply. When you eat, it recharges your glycogen levels. The lower your glycogen stores run, the more energy your body starts deriving from fat stores. When your glycogen is almost completely depleted, almost all of your energy is coming from fat stores.

In a "fasted" state such as first thing in the morning, your glycogen will be down a little bit from the energy you've burned through overnight. If you haven't eaten in a while, it'll be quite down. And so your body will start burning fat stores faster to pick up the slack.

But it all works out on balance. It doesn't really matter if you burn 1,000 kcal from stored glycogen or from fat. The body will balance it out in the end.

How much anyone has is dependent on a lot of factors, but when well fed you have about a full normal day's worth of energy stored in glycogen. And about enough for two hours of relatively heavy exercise (like a race pace half marathon). So if you haven't eaten since lunchtime yesterday and go out for a 15 miler this morning, you'll probably start eating into fat stores in the later stages of your run.
But if you only go out for 5 or 10k, it probably won't make much of a difference.

As Krusty_Clown rightly points out, doing a run at the start or in the middle of your 2-day fast is likely a poor idea since your body will be gasping for nutrition that you're just not giving it. Doing it at the end (i.e. just before you start pigging out) would be best if you insist on doing it. But any run should be slow and easy. Any high-intensity training would be a mistake.

average_runner

Enduro wrote: »

One of the things I love about discussing running nutrition is that you can be completely open with your competitors about what works, but people are so unquestionaly wedded to orthodoxy that they just won't listen. It's hilarious.

I listen to new ideas and love reading books on how the top runners do things.
But the fasted thing for 24 hrs once/twice a week doesn't sound a healthy thing.

I am all for running first thing in the morning without eating, I would do it every sat morning, basically because I will only get a small window to get out, so something has to give, usually food

RayCun

Enduro wrote: »

This is as good a site as any to read up on the ideas behind it. Lots of links to other articles and to scientific papers. There's a BBC horizon episode about I.F. here

Just noting that two of the positive changes supposed to be promoted by intermittent fasting are also/anyway produced by exercise
autophagy
increased production of HGH

TFBubendorfer

HelenAnne wrote: »

)

I always do my Sunday LSRs fasted (due to laziness re breakfast as mentioned before on the forum not for any fat burning plan or anything). Sadly, I never seem to lose any weight! Do the runs have to be a over a certain length or several times a week for the fasting to have amazing weight loss properties, or maybe I'm eating too much after the runs? (sorry to fixate on the weight loss side of it, but it would be nice if something I'm already doing could be tweaked for miraculous weight loss

In the end, weight loss comes down to burning more calories than eating or drinking them.

In that light, the length of one single long run isn't all that relevant as it's only a small piece of the jigsaw throughout the week.

My own experience with weight loss is that I easily drop 6/7 pound from an already reasonably low level over a few weeks just by cutting out processed sugar without making any other changes. I would suggest you try that first before making any drastic changes.

(sorry for the OT post )

HelenAnne

TFBubendorfer wrote: »

In the end, weight loss comes down to burning more calories than eating or drinking them.

In that light, the length of one single long run isn't all that relevant as it's only a small piece of the jigsaw throughout the week.

My own experience with weight loss is that I easily drop 6/7 pound from an already reasonably low level over a few weeks just by cutting out processed sugar without making any other changes. I would suggest you try that first before making any drastic changes.

(sorry for the OT post )

yes, once of my colleagues swears by the no processed sugar thing too. Thanks! Good idea!

Enduro

ooter wrote: »

Wouldn't know a hell of a lot about it personally but there's a lad called Barry Murray that I've listened to in a few interviews/podcasts and he talks about it as a good way to promote a fat burning state but he recommends you only run fasted 2 days a week max.
Did it myself a couple of years ago when training for DCM, ran all my weekend long runs on empty and I definitely think it helped as I got my PB that still stands.

As it happens one of his blogs popped up in my FB feed which is pretty relevant. So he practices the "skip breakfast" 16 hour daily fast himself, which is the route I'm heading down as well.

Enduro

HelenAnne wrote: »

yes, once of my colleagues swears by the no processed sugar thing too. Thanks! Good idea!

The single best thing you can do is eliminate added sugars from your diet, particularly in liquid form. Get it into your head that sugar is the enemy (Not fat). Have a look at this (american centric) documentary if you want some motivation!

The next major step would be to eliminate processed foods in general... just cook foods from the natural ingrediants (Vegetables, nuts, fruits (But NOT fruit juices), fish, meat, poultry, spices etc).

average_runner

Enduro wrote: »

As it happens one of his blogs popped up in my FB feed which is pretty relevant. So he practices the "skip breakfast" 16 hour daily fast himself, which is the route I'm heading down as well.

So you will have a meal at night time, go to bed, run in the morning and then eat around lunchtime?

Would your meals on either side be bigger than a normal day?

Enduro

average_runner wrote: »

So you will have a meal at night time, go to bed, run in the morning and then eat around lunchtime?

Would your meals on either side be bigger than a normal day?

In a working day... meal at lunchtime, training after work in the evening, followed by an evening smaller meal, and nothing until the following lunch. I'm not enough of a morning person to go running in the morning on a weekday. Skipping breakfast has the useful side effects for me of freeing up a little more time in the morning, and eliminating what was probably my worst meal from a nutritional POV. I haven't actually changed the size of my meals, but then I was a bit over my target race weight. It's been surprisingly straightforward so far, but I do need to adjust my timings a bit to hit a full 16 hour gap.

dublin runner

I'm very dubious regarding the merits of fasting but open to the idea. With that said, surely one should look at the basics of training first before resorting to what I feel may quite possibly be a very unhealthy endeavour (i.e fasting /starvation).

Personally, I will try to improve my training whilst continuing to eat a healthy balanced diet before going down that particular road.

Enduro

dublin runner wrote: »

I'm very dubious regarding the merits of fasting but open to the idea. With that said, surely one should look at the basics of training first before resorting to what I feel may quite possibly be a very unhealthy endeavour (i.e fasting /starvation).

Personally, I will try to improve my training whilst continuing to eat a healthy balanced diet before going down that particular road.

FWIW, I agree entirely with that approach. From a running POV, putting in the hard work in training (and recovery) is the basic, and there are no shortcuts.

I.F. isn't about running performance per se (Although it definitely has its uses in an endurance ultra context). It's more a general health thing. The OP's question was well put in that context, in that he asked if it was compatible rather than benificial.

average_runner

Enduro wrote: »

The single best thing you can do is eliminate added sugars from your diet, particularly in liquid form. Get it into your head that sugar is the enemy (Not fat). Have a look at this (american centric) documentary if you want some motivation!

The next major step would be to eliminate processed foods in general... just cook foods from the natural ingrediants (Vegetables, nuts, fruits (But NOT fruit juices), fish, meat, poultry, spices etc).

The second step I am pretty good at, press full of spices etc. Love making korma's, turkey meatballs etc First step I am pretty poor at :mad:

Enduro

average_runner wrote: »

The second step I am pretty good at, press full of spices etc. Love making korma's, turkey meatballs etc First step I am pretty poor at :mad:

I've got a sweet tooth as well, which means it's a bit more hard work for me than it should be. I do find that over time my tolerance for sweetness lowers, making things easier, thankfully! Big races can set that back though :mad:

Do you take orders for your homemade Korma

El Caballo

Enduro wrote: »

In a working day... meal at lunchtime, training after work in the evening, followed by an evening smaller meal, and nothing until the following lunch. I'm not enough of a morning person to go running in the morning on a weekday. Skipping breakfast has the useful side effects for me of freeing up a little more time in the morning, and eliminating what was probably my worst meal from a nutritional POV. I haven't actually changed the size of my meals, but then I was a bit over my target race weight. It's been surprisingly straightforward so far, but I do need to adjust my timings a bit to hit a full 16 hour gap.

Not to pry but this really sounds like the beginning of an eating disorder.

Enduro

El Caballo wrote: »

Not to pry but this really sounds like the beginning of an eating disorder.

I can see why you would think that, but I can assure you it isn't. Intermittant fasting isn't a food restricting diet. It's about the timing of your intake. Anyone who knows me in real life would probably laugh at the thought of me having an eating disorder (whilst hiding their food from me).

RuMan

A lot of this seems to come from the ultra running community. Is it relevant to those running 5/10k marathons ?

I'm open enough to new ideas and have been running on empty in the morning for a good few years now (mostly to get more sleep). I'm not exactly sure what the benefits of fasting are for most of us. Obviously if it means you can run a 24 hour race eating less it's a different situation.

happygoose

RuMan wrote: »

A lot of this seems to come from the ultra running community. Is it relevant to those running 5/10k marathons ?

I believe so, even middle distance. Frank Horwill of BMC fame was an advocate of fasting, he's some material on it on the Serpentine website.

TFBubendorfer

RuMan wrote: »

A lot of this seems to come from the ultra running community. Is it relevant to those running 5/10k marathons ?

I'm open enough to new ideas and have been running on empty in the morning for a good few years now (mostly to get more sleep). I'm not exactly sure what the benefits of fasting are for most of us. Obviously if it means you can run a 24 hour race eating less it's a different situation.

I started running on empty well before I got into Ultras.

Being an efficient fat burner is a very beneficial adaptation for a marathon runner. The rule of thumb is that your carbohydrate stored last about 20 miles, and I never had a problem with running out of gas over 26 miles.

For a 5k or 10k runner I'd expect there to be no measurable performance benefit, not that I'd know.

Edit: well there you go. See above post

Chivito550

happygoose wrote: »

I believe so, even middle distance. Frank Horwill of BMC fame was an advocate of fasting, he's some material on it on the Serpentine website.

Who is the best right now, and how does he eat?

http://www.bbcgoodfood.com/howto/guide/eat-athlete-mo-farah

Fasting is just another hipster type fad IMO.

Working class heroes

Thought that lad only ate that Quorn stuff.

average_runner

When did 10,000 or 5,000 meters become long distance?

ultrapercy

Chivito550 wrote: »

Who is the best right now, and how does he eat?

http://www.bbcgoodfood.com/howto/guide/eat-athlete-mo-farah

Fasting is just another hipster type fad IMO.

Training on depleted fuel stores makes good scientific sense for marathon and is used by all top coaches. Fasting is a different matter though and something like 5:2 would leave you vulnerable to illness and injury 1/3 of the time.

Enduro

I think ye're making the mistake of assuming that I.F. is about improving running performance. It isn't. It's about general health improvements (which could of course could/should consequentially improve running performance, but that's generally not the primary reason for adpoting it). None of the links I've posted on this thread relate to athletic performance (Well, Barry Murray's blog does to an extent). They're all about health improvements.

Myles Splitz

FWIW alot of decent science done on performance nutrition in Australia over last few years which tends to support the idea that while fat burning tendencies can be useful at sub maximal efforts, they can negatively effect performance at close to Vo2 max efforts (3k-5k)

Spirogyra

For the record I am neither trying to improve performance nor loose weight. This is something separate which I've seen quite a bit about. I'm just wondering whether it's indeed safe for me to regularly skip breakfast and run at a high intensity. They say it causes the body to repair,after even 16 hours without food.

Krusty_Clown

Spirogyra wrote: »

For the record I am neither trying to improve performance nor loose weight. This is something separate which I've seen quite a bit about. I'm just wondering whether it's indeed safe for me to regularly skip breakfast and run at a high intensity. They say it causes the body to repair,after even 16 hours without food.

Skipping breakfast is a long way off the original title of this thread. Skip breakfast and run occasionally. It'll be good for you. No harm.

RuMan

average_runner wrote: »

When did 10,000 or 5,000 meters become long distance?

Sprints (100/200/400), middle distance (800-1500m), long distance 5/10k. Fairly standard I thought ?

average_runner

RuMan wrote: »

Sprints (100/200/400), middle distance (800-1500m), long distance 5/10k. Fairly standard I thought ?

Would of thought long distance was marathon up and not a run that takes the top guys less that 30 mins

Spirogyra

Krusty_Clown wrote: »

Skipping breakfast is a long way off the original title of this thread. Skip breakfast and run occasionally. It'll be good for you. No harm.

Yes that was just an example but taken to it's 'full' it would involve a lot more.

Chivito550

average_runner wrote: »

Would of thought long distance was marathon up and not a run that takes the top guys less that 30 mins

Distances longer than the marathon are rarely discussed in mainstream athletics. As far as the standard Olympic, World, European championship track disciplines are concerned, it has always been generally accepted that sprints are 100-400, middle distance is 800-1500 and long distance is 5000-marathon.

Enduro

Chivito550 wrote: »

Distances longer than the marathon are rarely discussed in mainstream athletics. As far as the standard Olympic, World, European championship track disciplines are concerned, it has always been generally accepted that sprints are 100-400, middle distance is 800-1500 and long distance is 5000-marathon.

When did Marathon become a track discipline?

Chivito550

Enduro wrote: »

When did Marathon become a track discipline?

It's part of the Olympic, IAAF World Championship and European Championship programmes, so I included it for that reason.

Sacksian

And, to continue the track segue, 3k is an awkward relative of both middle and long distance. I'd consider it closer to "long distance" (mainly because it's the "distance" event for indoor and also because of the training) as do most classifications, but it's probably a genuine hybrid.

Clearlier

Spirogyra wrote: »

For the record I am neither trying to improve performance nor loose weight. This is something separate which I've seen quite a bit about. I'm just wondering whether it's indeed safe for me to regularly skip breakfast and run at a high intensity. They say it causes the body to repair,after even 16 hours without food.

As Krusty said that's a long way from the original question so I'm left a little confused as to what you're trying to find out.

FWIW - I don't eat before 12 noon and almost all of my running is done in the morning. I'll have fasted for anything from 10-14 hours. The relatively few hard sessions that I've done have been absolutely fine. I'm probably a touch off the performance levels that I'd hit if I ran in the evening but that's because I run better in the evening than I do the morning - it's just much more practical for me to run in the morning.

I suspect that my body would have taken a little while to adapt to it but I was injured when I changed my eating regimen and built up my training from scratch which gave my body plenty of time to adapt.