Fat loss - how to lose the bulge and gain the ripples

[SociallyChallenged]

I was under the impression that for burning body fat % the best training is high rep with short rests inbetween sets and not a low rep workout.

high rep workout should also prevent muscle loss during the cut. As long as the muscles are stressed, the body tries to sustain them.



I´m not sure if i´m correct here, but if his goal is to loose BF% an weight, this should be no problem or atleast the benefit of the cardio would still be greater then the benefit of hypertrophy.

No, high rep training works like aerobic training. It stimulates catabolism to a greater degree than low rep training. Because of this, protein degradation increases and muscle is burned as an energy source. At low reps and high weight, the load (and therefore repair response) is much greater. The body is forced to maintain the muscle mass, rather than degrade it, resulting in body fat being the primary energy source (if the individual is in a caloric deficit). High rep workouts don't quite work the same. They're middle ground in between general cardio and low rep weight work. Low reps, high weight is the most effective for maintaining muscle mass.

Hypertrophic pathways increase protein synthesis over protein degradation. This is important because it allows for muscle maintenance (or sometimes growth) even in a caloric deficit. Cardio is an ineffective way to lose body fat because it results in everything being burned - muscle, fat, and glycogen. With cardio alone (and no dietary modifications), research has shown time and time again that oxidative ability and fitness increase, but body fat does not change. With cardio and a caloric deficit, you lose muscle. With heavy weightlifting alone, beginners will often reduce their body fat % and increase lean muscle mass. In a caloric deficit, weightlifters have shown to lose predominantly fat compared to those participating in endurance exercise.

Therefore, weightlifting is actually a better means of losing weight than cardio. It stimulates pathways that maintain muscle mass and metabolize fat stores. Endurance pathways metabolize everything, resulting in catabolism of everything. With dietary modifications, weightlifting is always the best way to lose weight. Always.

 

[thatsright]

Thoughts/suggestions please:

I am overweight and have had no exercise in the last few years. While I don't eat much (in terms of calories) I eat unhealthy at night and on weekends. This has pretty much maintained my 6' 265lb frame. (I think) the most effective way to reverse this is with change of diet and joining a gym (build lean muscle and do aerobic). I'm committed to latter, but on the issue of changing diet after hearing a few folks and reading posts, perhaps I should do this first and then start exercise regime down the road??

Would it be too difficult to adjust to a new diet built around losing weight and try and start exercising? I'd like to try but it sounds like the prudent approach would give it a few weeks (2-4?) to adjust to what the new diet will be when I'm actually exercising?

What do you think? Obviously my desire is to start exercising right away. Bt I don't want to make it harder if I try and rush into it.

 

[SociallyChallenged]

First, we need to address some issues. You are overweight because you DO overeat (or have in the past). The types of food you eat aren't as important in weight gain as overall calories. Even if you're eating a 500 calorie surplus of fruits and veggies, you will still gain weight. It's thermodynamics.

If you want to exercise, go ahead and exercise. That will be a great step toward improving your health and losing weight. I suggest nutritional intervention before exercise because most people are concerned with weight before their health. You can start with either exercise or dietary changes alone, but I would suggest only starting with one. You don't want to overburden yourself and get tired of the whole weight loss process. Some people can do it, but I truly believe chances of success are greater if an individual slowly modifies their overall lifestyle.

You can do whatever you like, to be honest. Just make sure you aren't overdoing it. Read the entire fat loss sticky and follow it. You'll start seeing progress no matter what. Also, I don't quite suggest seeing a personal trainer, as you've mentioned in your other thread. Personal trainers typically have minimal certifications and are unqualified to truly write a program for you. I think you'd be wasting your money.

 

[HomerX]

No, high rep training works like aerobic training. It stimulates catabolism to a greater degree than low rep training. Because of this, protein degradation increases and muscle is burned as an energy source. At low reps and high weight, the load (and therefore repair response) is much greater. The body is forced to maintain the muscle mass, rather than degrade it, resulting in body fat being the primary energy source (if the individual is in a caloric deficit). High rep workouts don't quite work the same. They're middle ground in between general cardio and low rep weight work. Low reps, high weight is the most effective for maintaining muscle mass.

Hypertrophic pathways increase protein synthesis over protein degradation. This is important because it allows for muscle maintenance (or sometimes growth) even in a caloric deficit. Cardio is an ineffective way to lose body fat because it results in everything being burned - muscle, fat, and glycogen. With cardio alone (and no dietary modifications), research has shown time and time again that oxidative ability and fitness increase, but body fat does not change. With cardio and a caloric deficit, you lose muscle. With heavy weightlifting alone, beginners will often reduce their body fat % and increase lean muscle mass. In a caloric deficit, weightlifters have shown to lose predominantly fat compared to those participating in endurance exercise.

Therefore, weightlifting is actually a better means of losing weight than cardio. It stimulates pathways that maintain muscle mass and metabolize fat stores. Endurance pathways metabolize everything, resulting in catabolism of everything. With dietary modifications, weightlifting is always the best way to lose weight. Always.

You are right with this, but i think there is a difference between a fat/overweight/untrained person and a muscular person who tries to loose some BF for a better look, while maintaining muscle mass.

The key to loose weight is to eat less energy than you burn. The low rep weight training itself doesnt burn as many energy as a high rep workout (20 reps with 50lbs burn more energy than 5 reps with 100lbs).

A lot of overweight persons have problems to change their eating habits from one day to the other... They probably need to reduce their intake by 2000cal+ which seems impossible for them. But Instead of eating 4000cal they reduce to 3500cal after a few weeks to 3000 cal etc...
It is easier for them to increase the amount of burned energy in order to loose weight.

So with a low rep workout with no/little cardio you have to monitor your calorie intake more precisely.

with high rep + cardio they can eat more compared to a low rep workout and still loose weight.

You are right that this lost weight isn´t all fat and that there is the danger to loose muscle mass, but in the case of a untrained person there is not so many "unnecessary" muscle mass compared to Boybuilder/Powerlifter. And for a untrained person, even a high rep workout will force a great repair response.

The low rep approach is surely a cleaner way to reduce your weight while keeping your muscle mass, but for a untrained person it is probably faster to burn the weight whith high rep training + cardio.
Later, when they are used to a more strict eating plan and lost a serious amount of fat, they should switch to a low rep workout plan in order to build up/maintain their muscle mass.

At least this approach worked very good for one of my friends. He ate tons of crap and had problems to abstain from it. But he managed to be very active! He did cardio + high rep workout 4-5 times a Week and lost weight fast.
He was so motivated after this success, that he managed to eat much more healthy things and reduced his carbs/suger intake. Then he started to train together with me (low rep) and reduced its cardio workout to 1-2 times a week.
Without the fast success at the beginning i`m sure he would have lost the motivation!

 

[Ancalagon44]

How many reps/sets would you define as high or low? Is 12 a high number of reps?

Also.... a friend of mine says that some trainers have told him that the ideal heart rate to lose weight at is 140. Ie, during cardio, its a good idea to keep your heart rate at 140 to maximize fat burn, irrespective of your fitness level. Any higher, he says, and you start building fitness, which is counterproductive to losing weight.

Now.... I dont agree with this - I think its not so easy to separate fitness gains from weight loss anyway, and everyone's body will be different. Besides, it seems that those trainers were of the opinion that sustained moderate cardio is better for weight loss than short, high intensity cardio, which I think is untrue isnt it?

Does the 140 rule have any basis in science?

 

[HomerX]

How many reps/sets would you define as high or low? Is 12 a high number of reps?

personally i use the following numbers:

1-6 = low rep -> max strength
6-12 = medium rep -> max size
13+ = high rep -> max endurance

Does the 140 rule have any basis in science?

yes and no...

afaik the relative amount of burned fat is higher at low intensity levels. If the training is more intense, the ratio of energy from fat compared to the absolute amount of energy used decreases.
But the absolute amount of burned fat is higher with high intensity training.

50% of 1000 > 75% of 300....

If you want to loose a lot of weight (fat) the key is not to train at low intensity levels, because you want to burn as much energy as possible in order achive a negative energy level!

You wont loose weight if you burn less energy than you eat...

If you are a bodybuilder and you want to decrease your BF% whilst maintainig a negative energy level, low intensity cardio might be better compared to high intensity cardio, because you burn less muscle mass.
But in this case, cardio is anyway the wrong approach...

 

[Saulbadguy]

You must be above, even if only slightly, this while dieting at all times or else your metabolism will crash.

Link please.

 

[thatsright]

First, we need to address some issues. You are overweight because you DO overeat (or have in the past). The types of food you eat aren't as important in weight gain as overall calories. Even if you're eating a 500 calorie surplus of fruits and veggies, you will still gain weight. It's thermodynamics.

If you want to exercise, go ahead and exercise. That will be a great step toward improving your health and losing weight. I suggest nutritional intervention before exercise because most people are concerned with weight before their health. You can start with either exercise or dietary changes alone, but I would suggest only starting with one. You don't want to overburden yourself and get tired of the whole weight loss process. Some people can do it, but I truly believe chances of success are greater if an individual slowly modifies their overall lifestyle.

You can do whatever you like, to be honest. Just make sure you aren't overdoing it. Read the entire fat loss sticky and follow it. You'll start seeing progress no matter what. Also, I don't quite suggest seeing a personal trainer, as you've mentioned in your other thread. Personal trainers typically have minimal certifications and are unqualified to truly write a program for you. I think you'd be wasting your money.

A lot of what your saying makes sense. My feeling it would be worth a shot to first ease into the new diet and wait a few weeks (2-4) and then start exercising. Plan B would be to start exercising/diet modification at the same time relatively soon. This is what my friend is suggesting and he worked out a lot and has a fairly extensive knowledge on this. But its almost like he's saying its a waste of time to start exercising (if the goal is to loose weigh/tone up) without using supplements, shakes, vitamins at the same time. So in a sense, just starting to exercise would be half the battle and only have the potential to loose weight/build muscle. Given this idea, would it be worth a shot to try at the same time. Or would I be making it harder for me to stick with it long term?

 

[HomerX]

But its almost like he's saying its a waste of time to start exercising (if the goal is to loose weigh/tone up) without using supplements, shakes, vitamins at the same time.

You need NO supplements in order to loose weight... All you have to do is to make sure you are at a negative energy level...

Changing your eating habits will make it easier to eat fewer calories. A Protein Shake can be helpfull because they tend to make you full for a long time but you can also achieve this through eating a lot more veggies, lean meat etc by cutting out sugar and reducing carbs. The Goal is to feel full, despite eating fewer calories...

If you are able to change diet and start exercising at the same time depends on you and your motivation... Start slow if you are a beginner.

 

[brikis98]

The key to loose weight is to eat less energy than you burn. The low rep weight training itself doesnt burn as many energy as a high rep workout (20 reps with 50lbs burn more energy than 5 reps with 100lbs).

Weight training is an inefficient way to burn calories and its primary goal while losing weight is to maintain muscle mass. With respect to this goal, low rep sets are a much better choice. The difference in calories burned between a set of 5 reps versus a set of 10 reps is pretty minimal; the difference in strength/mass/power/etc gains from a set of 5 versus a set of 10 is much more substantial. If you are worried about not burning enough calories due to lower rep training, your time would be much more efficiently spent by either tweaking your diet or adding just a few minutes of cardio before/after your strength sessions (or on rest day). Walking at a brisk pace for 10-20 minutes (a good warm-up, btw) will probably more than make up the difference between low rep weight training and high rep weight training.

A lot of overweight persons have problems to change their eating habits from one day to the other... They probably need to reduce their intake by 2000cal+ which seems impossible for them. But Instead of eating 4000cal they reduce to 3500cal after a few weeks to 3000 cal etc...
It is easier for them to increase the amount of burned energy in order to loose weight.

If a person is seriously overweight, their BMR is significantly higher too. Therefore, they will NOT need to reduce their intake by 2000+ calories to lose weight. Like everyone else, they'll initially need to reduce it by ~500 calories per day. After they have lost a decent amount of weight, their BMR will be reduced and they will need to reduce calories further to continue weight loss, but this will be part of a gradual process and not as hard as trying to drop 2k calories immediately.

So with a low rep workout with no/little cardio you have to monitor your calorie intake more precisely.

with high rep + cardio they can eat more compared to a low rep workout and still loose weight.

Yes, high rep + cardio obviously burns more calories than just low rep training, but that isn't exactly a fair comparison. If you compare high rep + cardio to low rep + cardio, I'd bet that the latter group will end up happier with their body composition.

And for a untrained person, even a high rep workout will force a great repair response.

Initially, yes, any workout scheme will illicit a response from a novice. However, beginner gains don't last long and after that, the trainee who worked with heavier weights from the start will be able to keep making progress, where as the high rep trainee will be further behind, stall and have to change his routine to low rep training anyway.

 

[brikis98]

How many reps/sets would you define as high or low? Is 12 a high number of reps?

Take a look at this chart. "Low rep" training is 1-5 reps and is the most efficient choice for strength, power and hypertrophy. 12-20 reps is "high rep" and is best for muscular endurance.

Also.... a friend of mine says that some trainers have told him that the ideal heart rate to lose weight at is 140. Ie, during cardio, its a good idea to keep your heart rate at 140 to maximize fat burn, irrespective of your fitness level. Any higher, he says, and you start building fitness, which is counterproductive to losing weight.

Ugh, this is absolute garbage. Your friend should get rid of his trainer for tangling and screwing up so many concepts:

1. The 140 heart rate comes from the idea that there is a "fat burning zone" in cardio. That is, at a certain percentage of your maximum heart rate, your body uses a higher percentage of body fat as fuel instead of muscle. The first inaccuracy is that this doesn't happen at exactly 140 bpm for every person, as it varies with age, fitness, etc.

2. Even more importantly, it is almost entirely irrelevant to weight loss. The key factor in weight loss is that you burn more energy through out the day than you consume. The number of fat calories you burn during exercise is utterly irrelevant. To put it another way, "Caring how much fat is burned during training makes as much sense as caring how much muscle is built during training." It's also worth pointing out that the "fat burning zone" is only achievable during low to moderate exercise. If you instead use something higher intensity, such as interval training, you can burn a higher TOTAL number of calories; in fact, HIIT burns a lot of calories not just during the workout, but also the rest of the day after it. In other words, the fat burning zone is a myth in terms of being an efficient way to lose weight.

3. Increasing fitness is in no way counter productive to weight loss. I think this is so utterly self evident that it's not worth discussing. Seriously, avoid that "trainer" at all costs.

 

[brikis98]

You need NO supplements in order to loose weight... All you have to do is to make sure you are at a negative energy level...

Correct. Supplements are in no way a necessity for weight loss. If anything, they are a distraction that lets people think they can get away with crappy eating habits.

A Protein Shake can be helpfull because they tend to make you full for a long time but you can also achieve this through eating a lot more veggies, lean meat etc by cutting out sugar and reducing carbs. The Goal is to feel full, despite eating fewer calories...

Minor correction: protein shakes are typically helpful because they are a very quick/easy/convenient way to get a lot of protein. Although it certainly depends on the exact contents, the one thing most protein shakes are NOT is "filling". Liquid calories tend to be much less filling than solid ones: a shake with 50g of protein is usually not nearly as filling as 50g of protein from chicken breast, tuna, steak, etc. So if your ultimate goal is to feel full on less calories, whole/natural/unprocessed foods are typically the way to go.

 

[brikis98]

Given this idea, would it be worth a shot to try at the same time. Or would I be making it harder for me to stick with it long term?

It's really up to you. There is no hard or fast rule about it and the best choice depends on the individual. Having said that, this isn't exactly that big of a decision. You could start with both and if it becomes overwhelming, stick with just one until you can handle it... Or you could start with one and as soon as it's "easy" add in the other. As long as you get to comfortably doing both by the end, how you got there doesn't really matter and whether or not it took a few extra weeks to get there will not make a noticeable difference in the long term.

 

[SociallyChallenged]

You are right with this, but i think there is a difference between a fat/overweight/untrained person and a muscular person who tries to loose some BF for a better look, while maintaining muscle mass.

The key to loose weight is to eat less energy than you burn. The low rep weight training itself doesnt burn as many energy as a high rep workout (20 reps with 50lbs burn more energy than 5 reps with 100lbs).

A lot of overweight persons have problems to change their eating habits from one day to the other... They probably need to reduce their intake by 2000cal+ which seems impossible for them. But Instead of eating 4000cal they reduce to 3500cal after a few weeks to 3000 cal etc...
It is easier for them to increase the amount of burned energy in order to loose weight.

So with a low rep workout with no/little cardio you have to monitor your calorie intake more precisely.

with high rep + cardio they can eat more compared to a low rep workout and still loose weight.

You are right that this lost weight isn´t all fat and that there is the danger to loose muscle mass, but in the case of a untrained person there is not so many "unnecessary" muscle mass compared to Boybuilder/Powerlifter. And for a untrained person, even a high rep workout will force a great repair response.

The low rep approach is surely a cleaner way to reduce your weight while keeping your muscle mass, but for a untrained person it is probably faster to burn the weight whith high rep training + cardio.
Later, when they are used to a more strict eating plan and lost a serious amount of fat, they should switch to a low rep workout plan in order to build up/maintain their muscle mass.

At least this approach worked very good for one of my friends. He ate tons of crap and had problems to abstain from it. But he managed to be very active! He did cardio + high rep workout 4-5 times a Week and lost weight fast.
He was so motivated after this success, that he managed to eat much more healthy things and reduced his carbs/suger intake. Then he started to train together with me (low rep) and reduced its cardio workout to 1-2 times a week.
Without the fast success at the beginning i`m sure he would have lost the motivation!

There's actually no difference between the goals, nor should there be a difference between the pursuit of those goals. Overweight individuals will lose weight easier than muscular individuals who are cutting, but the process is the same.

I agree that calories in vs calories out is the main dilemma here. Overall calories burned is not the dilemma. Dietary modifications resulting in a 500 calorie deficit are not difficult to make. That's part of why I mention people getting their diet in order before getting on the lifting program. A 500 calorie deficit becomes easy after 4 weeks. When you introduce lifting, that skews the body's maintenance of muscle tissue. In a caloric deficit then, the energy must come from fat and glycogen stores.

What you're misunderstanding here is that high rep programs aren't as good at signaling hypertrophy. Hypertrophy pathways are responsible for protein synthesis and muscle maintenance. High rep programs actually induce protein catabolism (much like aerobic exercise) rather than prevent it. This means that both muscle and fat are burned, rather than fat.

On top of that, did you just call muscle mass unnecessary? People who want to lose weight want to lose fat. They don't want to become the skinny fat person. Maintaining muscle mass is essential (and typically what people expect) for people's self image and strength goals.

Also, I'm not looking for people to get the fastest results. The right way is frequently the way that takes a bit more work and a bit more patience. These individuals have taken years to put this type of weight on. Why would they lose it in a couple of weeks? Rushing this process is silly and frequently can result in overtraining, burnout, compensatory eating, stress, etc. Instead of doing weight training and cardio and HIIT as you suggest, all people have to do is lift and modify their diet. This is much simpler, which is what most people need. They don't need another complicated diet and they don't need a complicated workout. They just need some good information.

See, your friend enabled himself through exercise. I'm not here to promote that. I'm here to promote lifestyle changes through nutrition and exercise so that people can live happier and longer. When people do what your friend did, they have an increased risk of falling into exercise addiction or bulimia nervosa (except instead of vomiting to purge, they exercise). Exercise should not be a means to an end to let you eat all the crap you want. It should be something you do for enjoyment and health.

 

[SociallyChallenged]

Link please.

http://jap.physiology.org/cgi/content/abstract/12/2/230

Semistarvation induces decreases in overall metabolism and basal metabolic rate.

 

[SociallyChallenged]

A lot of what your saying makes sense. My feeling it would be worth a shot to first ease into the new diet and wait a few weeks (2-4) and then start exercising. Plan B would be to start exercising/diet modification at the same time relatively soon. This is what my friend is suggesting and he worked out a lot and has a fairly extensive knowledge on this. But its almost like he's saying its a waste of time to start exercising (if the goal is to loose weigh/tone up) without using supplements, shakes, vitamins at the same time. So in a sense, just starting to exercise would be half the battle and only have the potential to loose weight/build muscle. Given this idea, would it be worth a shot to try at the same time. Or would I be making it harder for me to stick with it long term?

Well, it seems like your friend isn't taking into mind that different people work different ways. If you're the type of person that tends to get overwhelmed when multiple things are going on in your life, then I wouldn't suggest starting diet change and exercise at the same time. If you're someone who can multitask throughout the day without a problem, then that might work for you.

Also, just to mention, supplements are completely unnecessary. If you get your nutrition honed in, you'll be perfectly fine. The only supplements I would suggest for overall health would be fish oil supps and a 1000-2000 IU vitamin D pill. Let me stress that they are completely unnecessary for weight loss. They just have some good effects on general health.

If you're this worried about starting both, just start one. What do you have to lose? If you change your diet and realize how easy it is and then decide to start exercising, then go for it. It's all about taking what you can in stride.

 

[thatsright]

Well, it seems like your friend isn't taking into mind that different people work different ways. If you're the type of person that tends to get overwhelmed when multiple things are going on in your life, then I wouldn't suggest starting diet change and exercise at the same time. If you're someone who can multitask throughout the day without a problem, then that might work for you.

Also, just to mention, supplements are completely unnecessary. If you get your nutrition honed in, you'll be perfectly fine. The only supplements I would suggest for overall health would be fish oil supps and a 1000-2000 IU vitamin D pill. Let me stress that they are completely unnecessary for weight loss. They just have some good effects on general health.

If you're this worried about starting both, just start one. What do you have to lose? If you change your diet and realize how easy it is and then decide to start exercising, then go for it. It's all about taking what you can in stride.

I talked to a co-worker who lost 80lb in the last 7 months and he stressed getting a diet down is key and should be first. I am going to start a low cab diet and get a hold on that first. I have come around a bit on getting hooked up with a gym/PT right away. The more I think about it, I think given my work schedule and life...trying to do both at once will be hard to stick to if I rush into both at once. I'll wait until I think I am well on my way to understanding what I need to do and how diet wise. Then perhaps 2 weeks out I'll look into going into the gym....

 

[Saulbadguy]

http://jap.physiology.org/cgi/content/abstract/12/2/230

Semistarvation induces decreases in overall metabolism and basal metabolic rate.

That's it? How about the effects on fat loss in those subjects?

 

[SociallyChallenged]

That's it? How about the effects on fat loss in those subjects?

You quoted me talking about a decrease in metabolism if you eat too little food. I responded with a peer-reviewed research article. What exactly do you want to know? What's your general question?

 

[Saulbadguy]

You quoted me talking about a decrease in metabolism if you eat too little food. I responded with a peer-reviewed research article. What exactly do you want to know? What's your general question?

I guess I just don't buy in to the whole "eat xxx amount of calories to lose weight, but don't eat too few or your metabolism will crash!!" line of thinking.

I think it could be dangerous to under-nourish because it may lead you to over indulge during the next meal.

 

[SociallyChallenged]

I guess I just don't buy in to the whole "eat xxx amount of calories to lose weight, but don't eat too few or your metabolism will crash!!" line of thinking.

I think it could be dangerous to under-nourish because it may lead you to over indulge during the next meal.

Well, it depends on a few factors. Firstly, it's very easy to reduce your calories by 500 if you're eating the right foods. You won't be hungry and you won't hate the weight loss process. Secondly, you can only put yourself in a certain calorie deficit before your body starts to break down your proteins for energy (through gluconeogenesis). Most people want to lose fat rather than muscle so that is another reason why a moderate caloric deficit is suggested.

However, you're not quite right to think that the amount of food eaten does not effect metabolism. The body is a very dynamic system and it will adapt to its environment to maintain homeostasis. I don't have time to find the article now, but there's research that shows people who have dieted for long periods of time have decreased BMRs. Also, as the article I posted shows, decreasing calories too much will reduce basal metabolism. These phenomena aren't just found in a few research articles, but have occurred so reliably that they are published in common textbooks (for both nutritionists and exercise physiologists). There are a ton of factors that induce this like stress hormones, catabolic enzymes, low circulating glucose/fatty acids, etc.

This is how the body reacts to dynamic stimuli. When that stimulus is simulated starvation, calorie wasting goes to zero. You should re-think your stance because there is quite a bit of research that supports it.

 

[brikis98]

I guess I just don't buy in to the whole "eat xxx amount of calories to lose weight, but don't eat too few or your metabolism will crash!!" line of thinking.

Then you may want to read this.

 

[Saulbadguy]

http://johnbarban.com/tag/metabolism/

 

[Saulbadguy]

Then you may want to read this.

Yeah. If you incur a 50% calorie reduction over a period of 6 months without any "cheats meals", you will probably go crazy. You will also lose muscle mass if you don't bother with weight training.

Big revelation.

 

[brikis98]

Yeah. If you incur a 50% calorie reduction over a period of 6 months without any "cheats meals", you will probably go crazy. You will also lose muscle mass if you don't bother with weight training.

Big revelation.

I guess you didn't bother reading the article I posted, so you missed all the key points:

1. "It is well established from longitudinal studies of human starvation and semistarvation that weight loss is accompanied by a decrease in basal metabolicrate (BMR) greater than can be accounted for by the change in body weight or body composition." In other words, your BMR doesn't drop just because you are losing muscle mass, but simply because you are eating too little. Your body actually tries to prevent tissue loss by reducing your energy expenditure in a way you can't control. This is great from a survival perspective, but if weight loss is your goal, it is horrendously inefficient: with too big of a deficit, for every 100 calories that you struggle to cut from your diet, your body reduces its expenditure by 80!

2. Moreover, diets with too much of a caloric deficit are not only inefficient, but also include a ton of negative psychological and physiological effects: lethargy, obsession with food, constant hunger, depression, loss of sexual drive, and so on.

3. Finally, to add insult to injury, it is harder to maintain weight loss from a starvation diet because your metabolic rate may stay depressed: "resting metabolic rate of our obese subjects remained depressed after massive weight loss despite increased caloric consumption to a level that allowed body weight stabilization.”

So, yes, you certainly will lose weight if you starve yourself, but it is an extremely impractical, inefficient, unmaintainable and difficult way to do it.