I did a water fast for a week and now my running has never been better! Anyone else tried this?

Yes.

That doesn't sound like a good idea, but I'm curious how you had the energy to get things done. Did you run at all during this time?

To be honest after the first 1-2 days it gets a lot easier. I did do an easy run every day and noticed that though I felt a bit depleted, my pace got faster without trying. Once I broke my fast, my pace was faster than what it was before I fasted.

Exactly how much weight did you lose in that week?

I lost 5-10 pounds during the week and then have lost a little more since, partly because it's helped regulate my appetite.

Silky Johnson wrote:

That doesn't sound like a good idea, but I'm curious how you had the energy to get things done. Did you run at all during this time?

Even a runner has pounds of stored energy. You just have to mobilize it.

Every time I see "water fast," I initially think someone is trying to go without water. Maybe I'm wrong, but I would just call what you did a fast, or if you feel the need to specify, a food fast.

You are burning fat instead of sugar. Those endless-energy runs are the reward of low-fat/high-carb +intermittent fasting, if you would like to continue. Just don't push the pace or you will feel like crap until you can get a modicum of glycogen back.

Nothing but water for 7 straight days? Not a bite of food at all?

Doesn't sound like a smart or healthy way to lose weight.

not so sure about that wrote:

Nothing but water for 7 straight days? Not a bite of food at all?

Doesn't sound like a smart or healthy way to lose weight.

If he lost 5-10 pounds then it was successful, no? So how is that not smart or healthy?

Probably 4 pounds or more was water weight, due to loss of glycogen which retains water.

Sounds interesting, but if I don't eat for a full day I get a raging headache. Never gone more than 2 days without eating, but I assume it'd only get worse. Did you not have spells of lightheadedness or major irritability?

Turbogeezer wrote:

Probably 4 pounds or more was water weight, due to loss of glycogen which retains water.

What does that have to do with what I wrote?

Just a little relevant information to fasting effects. Not particular to your post, which is why I didn't quote it.

idid wrote:

Turbogeezer wrote:

Probably 4 pounds or more was water weight, due to loss of glycogen which retains water.

What does that have to do with what I wrote?

Bobs Burgers wrote:

Sounds interesting, but if I don't eat for a full day I get a raging headache. Never gone more than 2 days without eating, but I assume it'd only get worse. Did you not have spells of lightheadedness or major irritability?

Lightheadedness will definitely happen, but headaches in my experience subside after about 2.5 days.

I do think it is stupid however, to only drink water. You're perfectly fine eating some vegetables, a light salad, yogurt, or even some fruit. Hell, even some toast with salted butter in the morning is fine.

Keep it under 200 calories at a time and the effects on your fast are minimal, but you'll get some electrolytes and feel better. No need to make this into a masochistic stunt and get terribly sick from lack of salt intake.

Also, *fasting might be dangerous for some people*. The advice of Your Doctor takes precedent over that of a few weirdos on LetsRun.

Don't expect fasting to help your running or athletics in any way. Animals eat or die for a reason.

It can be entertaining though, to try it for some time. And eye-opening, when you consider how ingrained the 3x meal system is, and how fearful many people are of skipping meals.

This is starting to sound a lot like what drug addicts say to newcomers, purporting the benefits of some recreational drug. Fasting shares a lot in common with taking drugs actually - there *may* be medicinal purposes for some people, but these are not well substantiated. It *may* be dangerous or even deadly, but this is rare if done in moderation. And it may come with altered feelings, mental state, or even perception of reality after a few days. Changes *may* or may not be long lasting upon return to normal routine. Effects are very *unlikely* to help sports performance much, but *may* decrease health.

Silky Johnson wrote:

That doesn't sound like a good idea, but I'm curious how you had the energy to get things done. Did you run at all during this time?

Read my post above.

After a few days I find that "energy" increases dramatically. Some will claim this is because of some kind of metabolic shift into fat burning but it's really not worth hypothesizing about.

What it feels like is a caffeine/tea buzz, without the jitteriness and with more clarity of thought. It feels like the outside world has slowed down but your thoughts have not, and visual acuity seems to increase dramatically, with details far away almost popping out at you.

If exercise is kept easy and low in volume, I find sleep increases dramatically in quality, while required hours drop by 30-40%. I find that I recall my dreams while fasting too. In the mornings I would wake after 4-5 hours and spring out of bed in a heightened state of alertness with absolutely no drowsiness whatsoever.

I will repeat - going a long time without eating is stupid and can have dangerous consequences. Approach this like you would a recreational drug.

So the way you'd recommend it is doing a 200 calorie/day fast for a week instead?

For light-headedness, take in extra salt (several teaspoons/day).

I've had a few questions about an intermittent fast for awhile now, specifically the 16/8 method. Maybe someone on here has some answers...

From what I understand, the idea behind the whole thing is that your body cannot process stored fat while insulin levels are high. You are essentially in an 'energy saving' state So, for the last few hours of the 16 hour fast, you have no/less insulin, and therefore are burning more fat for your energy.

Can anyone (preferably someone who knows what they are talking about) comment if this is correct from an physiological standpoint? It sounds logical to me, but I'm no expert by any means. I also can't readily find anything to confirm/refute that this is correct.

I do know that this method works well for me, at very least its an easy way to cut a few hundred calories from my day, with only a short period of actually being hungry. However, I don't know if it works because its just a caloric deficit, or if its because of the insulin level logic described above.