Intermittent Fasting

[Puncture Kid]

6 minutes ago, JayLow said:

Yea Layne's youtube persona is very obnoxious, but when you listed to long form interviews he is very thoughtful. He sets a very high bar for what he considers as acceptable evidence and he is open to changing his mind when good studies (well-designed human randomised control trials with large sample sizes) go against his ideas. At the same time, he resists charlatans (CGM/carnivore/fitstagram) with enthusiasm.

He also has some interesting videos (citing good studies, always) about the insulin claims of various diets.

Ok cool I will check his vids out. If claims are not science based and/or cherry-picked, I disregard.

I also look at the comments in all vids. That also gives me an indication of sentiment. Of course, you have to moderate that sometimes. The one thing about Dr Ekberg's videos is that he is a doctor and the comments from viewers that tried his advice are hugely positive.

[JayLow]

1 minute ago, Puncture Kid said:

Ok cool I will check his vids out. If claims are not science based and/or cherry-picked, I disregard.

I also look at the comments in all vids. That also gives me an indication of sentiment. Of course, you have to moderate that sometimes. The one thing about Dr Ekberg's videos is that he is a doctor and the comments from viewers that tried his advice are hugely positive.

Layne is also a doctor, but not a medical doctor (many of which know neither science nor nutrition). He has a PhD in nutrition science, specifically relating to protein. I try to not use comments as an indicator of value because random people on the Internet like me have no credibility and anecdote is not evidence. Comments also feed my confirmation bias too much.

[peetwindhoek]

On 1/31/2025 at 10:58 PM, JayLow said:

"Autophagy mode"

There is no evidence that fasting increases autophagy when you control for energy intake.

Fasting is useful because it helps restrict energy intake.

 

That was hard to watch, but I did. They don’t address whether the control group was fat-adapted. (Except if I missed that). Numerous studies show that both fat adaptation and intermittent fasting ) trigger autophagy, similar to caloric restriction. However, there are important differences between being carb-dependent and fat-adapted. Evidence suggests that IF, especially when in a state of ketosis, induces autophagy more rapidly compared to caloric restriction alone. This is largely due to faster glycogen depletion and enhanced metabolic flexibility in fat-adapted individuals.

[peetwindhoek]

5 minutes ago, peetwindhoek said:

That was hard to watch, but I did. They don’t address whether the control group was fat-adapted. (Except if I missed that). Numerous studies show that both fat adaptation and intermittent fasting ) trigger autophagy, similar to caloric restriction. However, there are important differences between being carb-dependent and fat-adapted. Evidence suggests that IF, especially when in a state of ketosis, induces autophagy more rapidly compared to caloric restriction alone. This is largely due to faster glycogen depletion and enhanced metabolic flexibility in fat-adapted individuals.

That said, I’m just a noob compared to the professionals, and I realize there are many factors at play. It’s not as clear-cut as Dr. Norton presents it. While I agree with most of the comments here, my stance is that this type of lifestyle might offer health benefits beyond just weight management.

['Dale]

What a highly recommended lifestyle habit.

Weight loss may be a cool side-effect. The real magic with intermittent fasting is its anti-inflammatory benefits, boosting brain vitality, steadier life force or energy, and enhancing mental health.

It has been valuable for me to 16:8 or 18:6 on most days as I navigate my auto-immune health challenges.

It's just eliminating those blerrie pastry fests on the weekend rides with my chain gang, eish. 😛

Edited February 5 by 'Dale

[lenzman]

Thank you for all the info and advice on this thread.

Been following fat adaptation recommendations as well as IF for a week.

Results have been great but carb flu and no power during exercise is a real thing.

Edited February 5 by lenzman

[NickGM]

27 minutes ago, 'Dale said:

What a highly recommended lifestyle habit.

Weight loss may be a cool side-effect. The real magic with intermittent fasting is its anti-inflammatory benefits, reducing brain fogginess, steady life force or energy, and enhancing mental health.

It has been valuable for me to 16:8 or 18:6 on most days as I navigate my auto-immune health challenges.

It's just eliminating those blerrie pastry fest on my weekend rides with my chain gang, eish. 😛

I've done little to no reading around this, but my partner started to do it and I joined her. Which in practical terms means that on days where I have not done a morning ride, I will not eat until 10am earliest. About 4 hours later than I normally would. It's been easier then I expected and my perception so far is definitely less fogginess and a sort of calm-but-alert feeling for the morning. This is all very "soft science" and nothing I've measured yet (although checking BP and heart rate wouldn't be hard at all). But my point is I've found it to be a net positive so far, and losing a few kilos was a nice side effect. I think a lot of our modern day eating and sleeping habits are unfortunate by-products of the industrial revolution.

[lechatnoir]

here's an anecdote - after living in Hout Bay and riding Chappies 100's of times, I beat my PR by 90sec on a ride where I was fully fasted after 4 days - that would be espresso, water and salt for 96hours. That's a fair chunk on what's quite a short segment.

It could be explained by all my other times being sluggish, or it being a particularly good weather day, but my experience showed a different story.

I can't explain it, but it sure makes for interesting thinking

I hasten to add that kind of thing never happened again

Why did I do that? I wanted to find out about my body. The only way I could was to try it myself. No amount of reading, podcasts, or YouTube bingeing will help. What works for others may not work for you, and what works for you today might not work tomorrow. Be open-minded and curious and reject all sacred cows

 

[love2fly]

2 hours ago, lenzman said:

Thank you for all the info and advice on this thread.

Been following fat adaptation recommendations as well as IF for a week.

Results have been great but carb flu and no power during exercise is a real thing.

I've not felt much of the carb flu but flat during exercise, yes definitely.

As per a previous post of mine, I have shelved trying to improve fitness and am starting with weight loss as my priority.

I'm doing flattish, approx. 30-45km  rides with some climbing on tar on my heavy dual suss MTB and keeping it low intensity as I'm 18:6 fasting and only eating at 12:00 and 18:00, thus riding fully fasted on water with some salt only.

I ride this 4 times a week and after 2 and a bit weeks have lost just over 5kg, my allergies and asthma have improved and my rides are no longer feeling like I'm bonked. Provided I keep the intensity down.

I have had to fig around for recipes as I soon got tired of omelettes and mince dishes....

Good luck.

PS, here's the keto pizza I made....

[ChrisF]

18 minutes ago, love2fly said:

I've not felt much of the carb flu but flat during exercise, yes definitely.

As per a previous post of mine, I have shelved trying to improve fitness and am starting with weight loss as my priority.

I'm doing flattish, approx. 30-45km  rides with some climbing on tar on my heavy dual suss MTB and keeping it low intensity as I'm 18:6 fasting and only eating at 12:00 and 18:00, thus riding fully fasted on water with some salt only.

I ride this 4 times a week and after 2 and a bit weeks have lost just over 5kg, my allergies and asthma have improved and my rides are no longer feeling like I'm bonked. Provided I keep the intensity down.

I have had to fig around for recipes as I soon got tired of omelettes and mince dishes....

Good luck.

PS, here's the keto pizza I made....

 

May I suggest you go see a specialist sports dietitian.  By the sounds of it, you are doing "the right thing", yet not getting the expected results.

 

Eating plans are incredibly complex, or rather the individual element.

 

The "perfect plan" may not work for the next person, simply because of some underlying medical condition, or simply genetics.

[lenzman]

26 minutes ago, love2fly said:

I've not felt much of the carb flu but flat during exercise, yes definitely.

I had to call in sick and tell my boss I am becoming fat adapted and now have carb flu.

 

[love2fly]

21 minutes ago, ChrisF said:

 

May I suggest you go see a specialist sports dietitian.  By the sounds of it, you are doing "the right thing", yet not getting the expected results.

 

Eating plans are incredibly complex, or rather the individual element.

 

The "perfect plan" may not work for the next person, simply because of some underlying medical condition, or simply genetics.

Hi Chris, I'm actually very happy with the results. The low intensity rides are to help burn fat rather than carbs, assisted by the low/almost no carb, highish fat and medium qty of protein.

I'm feeling better than when I started and don't struggle during the fasting period.

Lots of Keto recipes on YT and I've started experiment with them. The pizza (just an example) is fairly high in calories but virtually zero carbs.

[Puncture Kid]

11 hours ago, lenzman said:

Thank you for all the info and advice on this thread.

Been following fat adaptation recommendations as well as IF for a week.

Results have been great but carb flu and no power during exercise is a real thing.

Yes agreed, but my take on this is based on Dr Ekberg and my own experience:

If you are fat adapted you can exercise at aerobic levels easily, even during fast. But if you want to exceed that for a prolonged period then you may need carbs for glycolysis or have sufficiently topped up nutrient stores.

I did OMAD for whole of last week. Then went for a ride on Sunday. 30 mins at 140bpm to get to the trail and then 1.5 hr between 140-160. At the start of the higher intensity period I was pretty fatigued already. Then I took a sip of my wife’s Enduren. After a few minutes it made a huge change and I felt way better. 
My conclusion is basically that my nutrient stores were low because of the week’s OMAD and that the carbs helped. And / or I am not properly fat adapted yet to be able to ride on my belly fat at high intensity…

I think fat burning is likely much slower than glycolysis hence my need for the bit of carbs.

[Rapunzel]

I think we're sometimes too quick to adopt the "one size fits all" approach and fasting is no different. While it works wonders for many people, don't beat yourself up if it doesn't work for you. 

Ladies (and hubbies /partners who read this), fasting and intermittent fasting doesn't work the same way in women as it does in men. I attempted the IF approach and suffered from zero weight loss and a loss of muscle and strength. Having researched a fair amount, I came across Dr Stacy Sims (exercise physiologist and nutrition scientist unlike "doctors" marketing themselves on social media such as Dr Mindy Pelz, Dr Sten Ekberg and Dr Eric Berg who are all Chiropractors). She gives sound scientific advice based on peer reviewed studies and it is well worth watching this video, even if you do it in chunks over a few days.

 

[Mike Dewing]

On 1/29/2025 at 3:53 PM, ChrisF said:

 

The human body is a crazy thing ....

 

MOST diets comes back to a calory deficit ... that, or "switching" from carbs as fuel to using fat as fuel.

 

Metabolism, or rather a change in your metabolic rate, early onset diabetis (insulin resistance), and so many more can cause the body to go pear shaped (pun intended).

 

If a "healthy eating plan" and moderate exercise does not keep off the weight .... GO SEE A DOCTOR.  The risks associated with a web-based diagnoses is simply not worth it.

 

To the OP - hope you get to the bottom of this quickly.

Weight loss is calorie deficit.. end of story..

when creating that deficit by restricting diet then cutting carbs makes sense.. carbs are generally high in calories.. 

but when raising your consumption of calories by exercise completely cutting out carbs is going to make exercising painfully exhausting.. 

but I agree on GO SEE A DOCTOR.. if you are in a calorie deficit and not losing weight(and remember it doesn’t happen in five minutes, it took years to put on those pounds it takes long time to lose them) then you got something else going on and should get that checked out.. or, and this happens often, you think you in a deficit but you actually are not🤷🏼‍♂️.. and some are blatant liars🤣🤣.. 

Edited February 6 by Mike Dewing

[love2fly]

I started my keto and IF journey on around 20Jan. In the 2nd week I eliminated carbs but for berries, salad and a tiny bit of veg. 

I've done about 6 or 7 low intensity rides on the road on my MTB.

I'm 61 years old, my Max HR is 164 and I keep my HR around 110 on the flats and on the odd climb I might see 140 odd.

In 2 1/2 weeks I have lost just over 6 kg and haven't felt this good in a long time. The weight loss is visible and clothes are looser.

I am trying to make meals more interesting but my fall back is a cheesy omelette. I eat lunch at 12:00 and dinner at 18:00 and fast between.

I'm getting by on less than 2000cal daily, partly due to boring food but also due to no carbs and don't struggle with hunger.

I'm a foodie and previously lived to eat.

My rides are fully fasted and salt water only.

This may not suit all but I want to lose another 10-25 kg and prefer the cold turkey approach and am not prepared to go slowly does it.

Like I said, each to his own.