Does Exercising during Fast Increase Autophagy?

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Does exercising during intermittent fasting increase autophagy?

I knew that exercising during your fasting window was beneficial, and I usually do that, but I wasn’t sure whether that increased autophagy or not.

For example, I practice 17/7 intermittent fasting to activate autophagy, but when I exercise, can I decrease the fasting hours to gain the same autophagy effect?  In other words, can I do 16/8 or 14/10 to get the same benefits as doing 17/7 if I exercise? That was something I wanted to know. It would be cool if it did, wouldn’t it? Then, you won’t have to do 17/7. It would also make it easier to shift to early time-restricted feeding.

Well, Mike Mutzel from High Intensity Health has recently uploaded a video on it.

He said that autophagy is induced faster for people who exercise regularly.  For example, if you compare fit people and untrained people, among the fit people autophagy is activated after 12 hours of fasting while it takes 36 hours for unfit people.

He thinks, therefore, people who exercise don’t need to fast as long.

He says people who exercise regularly, not necessarily people who exercise during fasting, but either way, it seems that you can do shorter fasting if you exercise.

I don’t know what research he is referring to, so I don’t know the details of this research.

I wonder how many hours less you can fast to gain the same benefits as 17 hours, 24 hours, and 36 hours fast. According to Dr. Mindy Pelz, there are different stages in the activation of autophagy.

Different benefits of different lengths of fasting according to Dr. Mindy Pelz

Dr. Mindy Pelz says the amount of time you fast gives you different cleaning benefits; 16 hours, 17 hours, 24 hours, 36 hours, 48 hours, and 72 hours.

16 hour fasting has the following benefits.

fat burnings begin,

human growth hormones,

reduced inflammation,

increased ketones,

and improved energy and focus

17 hour fasting has the following

cellular detoxification,

cellular repair,

improved immune function,

and cancer prevention

24 hour fasting has the following benefits.

reboot intestinal stem cells,

reduces trymethylamine n oxide,

and increase longevity and survival.

36 hour fasting has the following benefits.

Reduced glucose stores

reduced insulin stores

increased fat burning



48 hour fasting has the following benefits.

reset dopamine receptors

reduced anxiety and depression

anti-aging antioxidant production

HGH increase by 500%

72 hour fasting has the following benefits. 

peak autophagy

immune stem cells

musculoskeletal stem cells

chronic conditions

accelerated healing

If you fast for 12 hours, do you get the same benefits as doing 36 hour fast?

Mike Mutzel was comparing 12 hours and 36 hours. Does it mean you get the same benefits as 36 hour fast if you fast for just 12 hours?

I don’t know. He didn’t clarify it.

What he said sounded like you get similar benefits as 16 hour fast, which is the common length of intermittent fasting, if you fast for 12 to 14 hours for people who exercise regularly. To get the similar benefits as 17 hours fast, you want to take the longer end, 14 hours. To be safe, 14 to 15 hours.

That is still good news.

If you are doing 17/7, eating lunch at 12 noon and finishing dinner at 7 pm, you can change to 14/10, eating at 9 am and finishing dinner at 7 pm, or do 15/9, eating at 10 am and finishing dinner at 7 pm.

It almost becomes like early time-restricted feeding, and you don’t need to skip dinner.

Early time-restricted feeding

Early time-restricted feeding is bringing the eating window earlier in the day such as 7 am to 2 pm, 8 am to 3 pm, and 9 pm to 4 pm if you do the 17/7 method. It is considered to be good because it matches the circadian rhythm. However, the drawback of this method is that you have to skip dinner instead of breakfast and dinner is often a family bonding time and it can be your ikigai.

By practicing 14/10 or 15/9, you can bring your eating window earlier without skipping dinner.

Anyway, it is better not to eat too early in the morning if you want to exercise in the morning.  If you eat at 7 am, you have to get up at 5 am to do your morning exercises.

Andrew Huberman says it is good not to eat within an hour after waking up, so even if you don’t do a morning workout, you still have to get up at 6 am to eat at 7 am.

In my case, I usually get up at 6 am and drink a glass of water and by the time I leave my house to do my morning exercise, it is 6:15, and I exercise for about 45 minutes. After that, I do eye exercises, pray at the house shrine, do Wim Hoff’s breathing exercise, and chant the Heart Sutra, which takes about 45 minutes altogether. Then, I have my first-morning black coffee.  One hour and 45 minutes after waking up. Andrew Huberman also says it is good to wait 90 minutes after waking up to take caffeine.

So, I drink coffee around 7:45. I check my e-mail and start writing my blog while drinking coffee. Time goes quickly and by the time I finish my coffee, go to the bathroom, and dry the laundry which I set to wash before drinking coffee, it is already 9 am. So eating at 9 am is early enough. I am not so hungry in the morning and I can easily wait until 10 am, too.

This is an option.

I will stick to my usual 17/7 schedule though. It isn’t hard to do at all by now, and I feel like my gut deserves a long rest anyway. I am happy to think that I may be getting the effect of 19 or 20 hours fast as an added bonus.

Anyway, combining fasting and exercise is a good idea from a holistic point of view, too. Just like diverse fiber can benefit the gut microbiome, diverse activities have synergetic effects on your well-being.

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