Hi guys, I am 76kg and 167cm tall.

So I've started this Intermittent Fasting (16/8, 8pm-12pm fasting, 12pm-8pm eating period), coupled with LCHF. (brunch at 12pm which is 2 hard boiled eggs, cucumber and tomato, dinner at around 7pm which is 2 piece of chicken fillet and 2 type of vege, typically broccoli / cauliflower + bak choy / romaine lettuce). In 1 week, I've lost 3kg. I jogged on Tuesday, Thursday and Saturday, during none fasting period.

I've been reading online coz I want to do Fasted Cardio. Which means I'll wake up at 7am, jog with an empty stomach. But from my research, there is 2 camps, and it's very 50/50

Response A: yes it will burn even more fat.
Response B: it will still use ur muscle energy or something. The side effect will be ur muscle deteriorates.

Would like to know any fitness guru's take on this topic.

IMO, it's better that you try it on your own since everyone's body works slightly different. Even if others could give you advice, they're anecdotes which may not reflect the truth. Personally, I wouldn't suggest you do it alone since there's always a chance of passing out from hypoglycemia.

P/S: Not a fitness guru.

Low Intensity Steady State exercise like jogging is great for fat burning - but needs a longer duration. It also doesn't need to be done fasted but if you're doing 3 sessions at half an hour a week, frankly it's not a lot.

If you're doing it with a huge calorie deficit you'll burn muscle - no way around it. I mean IF is supposed to increase metabolism and reduce calories right? Make sure you calculate your TDEE and match your calorie intake so that you can lose weight safely

Also, I'm not a fitness guru.

when losing weight...muscles will deteriorate no matter what...
the diet will determine how fast it deteriorates...urs seem fine anyway.

in the end, if not much muscle...just concentrate on losing weight only...muscle can rebuild later...and the cycle continues...

Yea. I'm reducing my calories and carbs intake as well during my none fasting period. Just want to hit the healthy BMI. Am overweight now.

I think I'll try out tmr morning for the fasted jog. Let's see how it goes. My previous week I jog for 5km, 6km, 6km. Should I still target the same 6km? Or should I look to reduce since I'm doing it during fasting period?

If you don't care about your muscle then you can go extreme low calorie for faster result.

If you want to preserve your muscle then best eat at slightly below maintenance and higher protein intake.

People say fasting works cause they don't have much time left to consume more calories in that particular day. Its all Calorie In vs Calorie Out.

Point B is obvoius if you are really lean. Otherwise, nothing much happened to your muscle.

This post has been edited by dewa_poyo: Oct 19 2020, 12:14 PM

I workout empty stomach in the morning. Real actual heavy lifting. Last meal the day before between 11-11.30 pm.

I do this simply because i feel better, and the timing i workout is too early to get any food actually digested. I once tried working out abit later so that i can get some quick digesting breakfast in. But tbh my workout had always been worse.

Truth to be told, weight lost is still pretty much calories in calories out. As much as some ppl who claims they track and not lose/gain weight. It just means that 1) their tracking is not accurate enough or 2) they overestimate the amount of calories burnt.

You wanna lose mainly fat, eat less and do resistance training so that the body will keep the muscle. Its designed to survive in the first place.

At a certain point, you will eventually lose muscle regardless of fasted cardio or not.

This post has been edited by axtray: Oct 19 2020, 12:35 PM

Both A and B will happen. But at what ratio I don't know.

It's not that.
Calories in and calories out.
but many people don't realize calories in affects calories out.

Let say your current metabolism is 2200 calories a day based on your intake of 2200 calories a day.
So you reduce to 1700 calories and get 500 calories deficit. What happens in the long term.

week1 -- calories in=1700, calories out = 2200 deficit = 500
week2 -- calories in=1700, calories out = 2100 deficit = 400
week3 -- calories in=1700, calories out = 2000 deficit = 300
week4 -- calories in=1700, calories out = 1900 deficit = 200
week5 -- calories in=1700, calories out = 1800 deficit = 100
week6 -- calories in=1700, calories out = 1700 deficit = 0, <----- At this point no more weight loss and this is where most people complain that they are no longer losing weight. Body metabolism have adapted to low calorie diet.

Now what happens when you start to eat 1900 calories which is still lower than your original intake. ... then you gain weight despite eating less than what you originally eat.

This post has been edited by Drian: Oct 19 2020, 05:29 PM

That means I need to do ttde calculation everytime I drop in weight right? That would be more accurate?

Then when does it stop?
If you're at 1600 calories , do you still starve yourself and go to 1200 calories to lose more weight? It's not sustainable.

Should read this. They were having 1200 calorie diet and their metabolism dropped by 800 calories a day.

https://thefastingmethod.com/biggest-loser-...LOSING%20WEIGHT.

What you're showing is just saying that you need to always know your new TDEE after you lose weight. I thought that's a given. Take into account me right now at 100 kg doing the same 5 days a week 2-3 hours gym will definitely burn more calories than when im at 90kg with same activity level.

What people fail to realize is that, the TDEE that is calculated from a standard TDEE calculator is not accurate. people may be loosing weight initially. but when the weight lost stops, you need to recheck what you're doing (apart from recalculating your TDEE with your new weight).

If you are too drastic with the caloric reduction, it will affect the non exercises activity thermogenesis. and this can easily change the overall TDEE for the day from the actual amount the TDEE Calculator shows, to way less (up to 500 cals).

This post has been edited by axtray: Oct 19 2020, 06:26 PM

Your calculation is correct but that's not metabolism adaptation. Its just your bodyweight dropped hence doesn't require that much energy to move.

So when your bodyweight dropped, then you need to recalculate the TDEE. Simple as that. Or everytime you drop 1kg, you reduce 100kcal.

One should not just reduce "calorie in" to lose weight.

The best way is to bump up your "calorie out" so that you can get alot more macro & micro-nutrients for healthy body.

Short answer is to stop being lazy. Exercise more, move more. Stop lying on bed for social media and sit whole day to watch tv/play games. Go for a walk, wash, clean, take stairs instead of elevator, etc.

There are 2 things :

1.) Due to body weight
2.) Due to body adapting reducing its metabolism to the lower calorie input.

180cm, 30yo, M

1.)100kg, BMR =1980kcal
2.)90kg,BMR = 1880kcal
3.)80kg, BMR = 1780kcal
4.)70kg, BMR =1680kcal

BMR DROP = 300CAL/30KG = 10cal/kg
https://tdeecalculator.net/

If you need to reduce 100cal/kg, then you're TDEE drop is due to body adapting to your input calories , NOT due to body weight.

Someone who once weighs 100kg needs to consume -3000kcal to maintain his weight at 70kg? That metabolism is probably less than a 10 year old girl.

This post has been edited by Drian: Oct 20 2020, 11:47 AM

calorie deficit.

Calories in calories out. Doing it fasted or non-fasted DOES NOT overwrite the laws of thermodynamics. The only side effect I could think of if you're doing cardio fasted is that you're gonna feel like shit and have no energy. So, eat something so you can perform the exercises the best that you can.

the stupid response A and response B you're listing - those effects are so small and minute, it do not matter.

Fasted cardio is to consume leftover blood glucose before 1st meal. But it is also a known method among fitness elites not to gain excessive fat.