Does exercising while fasting increase fat loss?

ABC News' Dr. Jen Ashton answers viewers’ health and COVID-19 questions.

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[AgentSmith]

If you're skinny, you shouldn't try to fast very long unless you have experience, but if you're obese, it's a great way to lose weight. It does require some discipline though.

[emerson-lfow]

1:18 shes correct, long duration low intensity (walking for miles ) best way to burn fat when fasting..I fasted for 37 days & walking did it

[jayson]

If you start fasting for 3 days, you don’t want to eat again. Your hunger subsides

[Dooger]

Fasting works better if you have plenty of muscle mass to begin with. Fat just melts away

[benignoagbayani]

Fasting would be when glycogen stores drop. Ketosis begins. 20 to 30 hours. If there is exercise within this time it would shorten. Fat burning and not muscle sacrificing is best with little stress

[elirez]

She's making it sound complicated when it's not. Go on a water only fast for a few days and exercise. Your body will use up what you have stored. She said there is no simple answer, but there is a simple answer: Yes, you will lose fat. Look at every survivor type of show or look at people living with little food in other countries. It's just common sense.

[abelbastida]

Did anyone else miss if she actually and directly answered the question?

[omeatai]

Some of these comments are actually funny. She actually has a point. High intensity Training (HIIT) will make you burn fat but some of that will be converted to toned muscles which makes the fat burning process slower. So in the short-term you burn less fats with HIIT than if you go for long daily walks above 10000 steps (approx 1-2 hours walk). But in the long-term you burn more fat with HIIT because the muscles developed increases your daily metabolic resting rate, so you burn more fats even when you are resting as your muscles are trying to maintain themselves, that's why body builders eat alot.
So in summary, do both HIIT and endurance walks (cardio) to get both short term and long term benefits.

[Sora_Nai]

It's not true that doing longer and less intense exercise burns more fat, calories, or energy. Studies show that you get the same results exercising at low intensity for long periods of time as doing high intensity shorter periods of time. Though doing high intensity for shorter time is how you build muscle more muscle the higher your maintenance caloric burn rate so you technically burning more fat, energy, calories with higher intensity shorter duration exercises as you build muscle which burns more fat.

[scotthunt]

She clearly had no idea what she’s talking about regarding fasting. It’s pretty simple, Fasting for long periods decreases insulin, Which eventually converts the metabolism to take energy needed from the fat stores. Once the body is in this fat adapted state you’re in what is known as “ Ketosis “ Once the body is using energy in this fasted state of ketosis the body is eating itself which is known as “ Autophogy “ Excercise increases and stimulates Autophogy therefore the answer to that is yes Exercise whilst Fasting does increase fat loss .

[ayeshaa]

I have to say after their affair came out now you can see all the sexual innuendos (between Amy and TJ) in their conversations, and it makes it 10x funnier but great insight on the exercise thing lol

[michellejade]

I was in ketosis my entire pregnancy & I never fasted 36 hours. I wasn’t fasting period.

[DarciWhither]

"Did you send this one in Amy?"
Way to call her fat Jen. LMFAO

[Labor_Jones]

... 2 minutes and I'll know!
I've experimented with FASTING every other day last year for 45 days, 60 days, and 90 days and I'm about to do 120 days! *It's not easy and pretty crazy how it works on a body!* _I'll eat one day and not eat next. That means 60 Days of FASTING soon!_

[Labor_Jones]

I hate disappointment so I had to come back later just in case....
.... Low and Slow and Long, interesting because I think I feel I do that naturally.
36 hours! What.... who is the Czar of FASTING come up with that?
I heard another 'expert' say 19 and I was surprised, but I still did 24.

[elizabethmcnamara]

If you want to do a long fast. DON'T EXERCISE! you can walk or go the shops but working out will make you so weak you will want to quit after day 1. I am 2 weeks into my fast and I walk but that is it. when I start eating I will exercise but now I have an excuse to relax and read a book etc...

[Kenny-dfgm]

she has no idea of what she is talking about, she needs to re-educate herself on fasting and the benefits. Why doesn't this show bring on Thomas Delauer and get some truth about this subject?

[inshaallah]

A "real" fast isn't 36 hours... LOL

[marchfifth]

This comment section proves 2 things. The doctor has no clue what she is talking about and every single commenter has no clue what they are talking about. lol

[robjohnson]

She literally did not answer the question.