The Metabolic Slowdown Thread

[lee__d]

Yes, we know there is no true starvation mode, i.e. your body can never outrun a caloric deficit. What we do know, is that your body will make metabolic adaptions to combat a caloric deficit. Perhaps, your bmr will decrease, or your body will become more efficient at burning calories through activity (thus burning less calories for the same activity than when you began your cut).

Now, a lot of times these issues only affect those dieting down to contest leanness. However, any deficit will cause metabolic adaptations (however slight they may be). Any prolonged cut will see more drastic issues.

I wanted to consolidate some of the information I have come across on this topic in one thread.

Just note, when I say Metabolic issues I mean anything that could be affecting one's tdee, includes hormonal issues and what not.

General Metabolic Rate info

LBM Maintenance & Metabolic Slowdown

Permanent Damage

Permanent damage follow up


Layne speaking directly about metabolic damage.


Berto speaking of maintaining low bf levels, which I believe is relevant.


Eric Helms discussing the subject. There are 6 parts to this Q & A, I definitely recommend watching them all, but it would be redundant for me to link them all imo.


Helms speaking of refeeds and carb ups.



This should be a good start for most of you.

Please note: Most dieters will not be suffering from metabolic slowdown to a degree where it will sabotage their weight loss efforts. The most common cause of weight loss stalling is inaccurate calorie counting (or inaccurate estimations of one's maintenance, thus leading to a small or non existent caloric deficit). Please do not use this thread as an excuse. Make sure you're counting is accurate. The information here is great for everyone, but using metabolic slowdown as the sole reason of one's stalled weight loss is likely to be a last resort.

[lee__d]

Add whatever links you have, and share your personal experiences.

[PhiSig2298]

Best thread in this section.. Reps off spread, OP.


I was dealing with metabolic slowdown not too long ago. I was doing extremely low calories (1,800) for my size, lifting & cardio. I stalled out & lowered calories even more. Lost a few lbs & stalled again. Did research on metabolic damage & reverse dieting. Took a couple months to slowly bring calories up & stopped cardio. Now, cutting again @ 2,500 calories with minimal cardio (mostly metabolic resistance training) and losing FAT. Feels good to eat like a normal human & lose.

I have progress pics in my log that's below in my sig that shows exactly how resetting metabolism helps.


Once again, excellent thread!

[lee__d]

Thanks, Phi. Its a seriously overlooked topic.

[dmacdonal9]

From what I've learned, it seems to me that you can really only affect small changes in BMR (10% maybe?), but that you can cause massive unintentional swings in TDEE through reduced NEAT and other adaptations.

I think it's misleading when we refer to the global reductions in TDEE as "metabolic damage", because so many people hear that and focus solely on the BMR component through hormones, thyroid and such. Layne does this in his video and I think it clouds the issue.

Here's some stuff I've collected:

NEAT & sedentary interruptions

TDEE changes from bulking to cutting

Longer term adaptations to a deficit

The last one has some really great stuff clearly separating the effects on BMR from TDEE.

[lee__d]

From what I've learned, it seems to me that you can really only affect small changes in BMR (10% maybe?), but that you can cause massive unintentional swings in TDEE through reduced NEAT and other adaptations.

I think it's misleading when we refer to the global reductions in TDEE as "metabolic damage", because so many people hear that and focus solely on the BMR component through hormones, thyroid and such. Layne does this in his video and I think it clouds the issue.

Here's some stuff I've collected:

NEAT & sedentary interruptions

TDEE changes from bulking to cutting

Longer term adaptations to a deficit

The last one has some really great stuff clearly separating the effects on BMR from TDEE.

I will read those when I can, got a little busy at work so I bookmarked them. Just wanted to say, Layne is speaking mostly about contest prep dieters. Also, anecdotally, people who have worked with contest prep dieters have seen ultra low calories plus tons of cardio yielding no fat loss. So while there may not be BMR slowdown per se (or maybe there are), I would guess there's more going on that simple reductions in NEAT. Yes these are the extreme cases and most regular dieters won't have to worry about it. NEAT reductions due to lethargy will have an effect, but they can take away that lengthy periods of low calories is not healthy.

[cunfewzed]

Really strong thread lee. Repped (when off spread). Nothing to add to what you already have here.

[cnh57811]

Stick this.

[RRJ]

I wonder why some individuals seem to be more affected by it than others. Over the last 3 years I've spent more than 24 months cutting. A lot of it was anywhere between 1700 to 2000 calories, with 3x weights and 3x 45 minute cardio per week. My maintenance is still right around 2850, which is what it's been for quite some time (it was higher than that at 350 lbs, of course, but I was practically doing squats just by getting out of my chair).

[truushot]

I wonder why some individuals seem to be more affected by it than others. Over the last 3 years I've spent more than 24 months cutting. A lot of it was anywhere between 1700 to 2000 calories, with 3x weights and 3x 45 minute cardio per week. My maintenance is still right around 2850, which is what it's been for quite some time (it was higher than that at 350 lbs, of course, but I was practically doing squats just by getting out of my chair).

I'm in this category. I've been cutting on 1600-2000 calories for 10 months and my TDEE seems hardly effected.

[MulattoRance]

Beautiful, can't wait to read all these links later.

Been cutting for a good 8 months now, and unfortunately when I started I was a total bro, doing 2 hours of LISS every day, with no idea what I was doing. Since then, having found this site, I've learned about TDEE, tracking calories/macros, etc., gotten my diet in check, and reduced to 1 hour of LISS 6 days a week. I want to reduce it even more, but I'm already on 2000 calories and am afraid of how low I might have to go now with no cardio.

All that to say, I do believe I have been affected by some metabolic adaption/down-regulation/whatever you want to call it. Some time back I took a two week diet break with no cardio and 2400-2600 calories and I went up 7 pounds (that's AFTER the water weight had come back off and been accounted for, 2 weeks back into dieting.) Not looking forward to the process of fixing this damage.

[lee__d]

I wonder why some individuals seem to be more affected by it than others. Over the last 3 years I've spent more than 24 months cutting. A lot of it was anywhere between 1700 to 2000 calories, with 3x weights and 3x 45 minute cardio per week. My maintenance is still right around 2850, which is what it's been for quite some time (it was higher than that at 350 lbs, of course, but I was practically doing squats just by getting out of my chair).

I'm in this category. I've been cutting on 1600-2000 calories for 10 months and my TDEE seems hardly effected.

Depending on how overweight you were when you start could delay the process (or at least allow for you to continue cutting for a long time without being affected by the slowdown that has occurred). That said, 2000 is low imo, but not horribly low where people will trash their metabolism (1600 is way low though imo). That said, reverse dieting can still be beneficial and allow you to continue cutting more easily.

[gloria7]

sticky this!

[truushot]

From what I've learned, it seems to me that you can really only affect small changes in BMR (10% maybe?), but that you can cause massive unintentional swings in TDEE through reduced NEAT and other adaptations.

I think it's misleading when we refer to the global reductions in TDEE as "metabolic damage", because so many people hear that and focus solely on the BMR component through hormones, thyroid and such. Layne does this in his video and I think it clouds the issue.

Here's some stuff I've collected:

NEAT & sedentary interruptions

TDEE changes from bulking to cutting

Longer term adaptations to a deficit

The last one has some really great stuff clearly separating the effects on BMR from TDEE.

Longer term adaptation. How did you interpret the study? Did I read it wrong, or did it basically suggest that you are far better off exercising while cutting calories then not?

[dmacdonal9]

Longer term adaptation. How did you interpret the study? Did I read it wrong, or did it basically suggest that you are far better off exercising while cutting calories then not?

Yeah, CR+EX got better results, in that they experienced a net TDEE increase, whereas the CR only group had a net decrease (after adjustment for calories burned in exercise itself). Both were pretty long term effects that persisted into weight maintenance phases. In both the increase and decrease, some of it appears to be from BMR and some from activity.

[truushot]

Yeah, CR+EX got better results, in that they experienced a net TDEE increase, whereas the CR only group had a net decrease (after adjustment for calories burned in exercise itself). Both were pretty long term effects that persisted into weight maintenance phases. In both the increase and decrease, some of it appears to be from BMR and some from activity.

Now we need a study that measures CR+EX where the EX is just weight lifting....

Thank you, great stuff.

[TomLambert]

Stick this.

I second this

[Kevin71]

Good thread. Seems to be a common question and there is a lot of knowledge in the OP.

[lee__d]

From what I've learned, it seems to me that you can really only affect small changes in BMR (10% maybe?), but that you can cause massive unintentional swings in TDEE through reduced NEAT and other adaptations.

I think it's misleading when we refer to the global reductions in TDEE as "metabolic damage", because so many people hear that and focus solely on the BMR component through hormones, thyroid and such. Layne does this in his video and I think it clouds the issue.

Here's some stuff I've collected:

NEAT & sedentary interruptions
This is a good study, theoretically, and relevant since it speaks of ways to increase an otherwise sedentary workdasy. However, I don't feel it is quite relevant to the purpose of the thread. Not to mention, in practice, people may walk around to get snacks (as mentioned in the study)

TDEE changes from bulking to cutting
Full text: http://ajcn.nutrition.org/content/64/3/259.long

An 8.3% reduction in BMR seems significant over 12d, imagine a year of cutting. Yes weight loss itself will contribute to a lower BMR, and this was due to a 7lb loss in 12 days (which is crazy). I plugged in 200lb and 193lb (all other stats equal) in a bmr calculator and got 1688 and 1656 respectively, which would be a 1.8% drop. A sign that big deficits can cause quick metabolic adaptions themselves? The paper says these changes were small in relation to the deficit, but unless I'm misunderstanding, they are large if you consider the bmr differences if they didn't come from dieting (i.e. 200lb man vs 193lb man - same heigh, age, etc.).






Longer term adaptations to a deficit
this looks like the full text: http://jama.jamanetwork.com/article....icleid=1108368
6 months, a nice longer term study (even so, we see people cutting here for upwards of a year or more)
"Participants were provided with all their food from the last 2 weeks of baseline through week 12. Participants ate 2 meals at the center each weekday, with 1 meal plus snacks packaged for take-out. During weeks 13 through 22, participants self-selected their diet based on individual calorie targets. During weeks 22 through 24, 2 meals per day were provided at the center, with 1 meal and snacks for take-out. "
God I wish they could have fed them for the whole study.

Results:; (2) a metabolic adaptation (decrease in energy expenditure larger than expected on the basis of loss of metabolic mass)
Which suggests there is something going on in the body to adapt to the prolonged, low energy intake. NEAT adaptaions? Maybe, but " There were no significant changes from baseline in the level of spontaneous physical activity or in the thermic effect of food expressed as percentage of energy intake.", I would assume this is for all groups....>>>"Spontaneous physical activity and the thermic effect of food were not changed from baseline. However, even if these 2 factors can account for some of the metabolic adaptation, the thermic effect of food accounts for only 10% of daily energy expenditure,44 and the cost of activity is already accounted for by a decrease in body weight. Therefore, these 2 factors can only account for a minor part of the metabolic adaptation."

"In this study, we observed a metabolic adaptation over 24 hours in sedentary conditions and during sleep following 6 months of calorie restriction. The metabolic adaptation in the calorie restriction with exercise group was similar to that observed in the calorie restriction group, suggesting that energy deficit rather than calorie restriction itself is driving the decrease in energy expenditure. Importantly, the metabolic adaptations were closely paralleled by a drop in thyroid hormone plasma concentrations confirming the importance of the thyroid pathway as a determinant of energy metabolism.43 Of significance, the metabolic adaptation occurred in the first 3 months of the intervention, with no further adaptation at 6 months, even though weight loss continued in the calorie restriction and calorie restriction with exercise groups."
To me this says, yes metabolic adaptations occur, but still cannot outrun a true calorie deficit. I also wonder if macronutrient intakes ended up changes (i.e. more carbs at times for some).


The last one has some really great stuff clearly separating the effects on BMR from TDEE.

Also, wow: http://calerie.dcri.duke.edu/ Comprehensive Assessment of the Long Term Effects of Reducing Intake of Energy (CALERIE)

[dmacdonal9]

To me this says, yes metabolic adaptations occur, but still cannot outrun a true calorie deficit.

Yeah, I think that's the most critical point. You can erode the deficit a little bit from metabolic adaptations, and a little more from TDEE (NEAT) reductions. But you will still have some deficit.

But then you throw in a few missed calories in the tracker and an error or two in portion size, and you've got a dieter eating at maintenance.

[JOSEF RAKICH]

Best thread I have seen. Ever.

[matt1942]

Bookmarked. Thanks for putting this together.
+rep

[qurs]

Great compilation and resource. Haven't watched the videos myself but it took me a while to research this stuff by myself in the past. Will watch later to see if what I learned was accurate, i.e., about a 10% adjustment in efficiency.

[GotrippedDOTorg]

Best Post ever!

[PhiDelt234]

5 star thread, I had to reset by cut by raising my deficit higher. Now I'm losing again

[PhiDelt234]

Best thread I have seen. Ever.

your calorie deficit is perfect, it isn't too high or too low for your stats.

[munkeyfunk]

Great Thread!!!!

[stingray72]

Ive found for me since I dont have tons to lose is to stagger out the cutting phases to the length that my body doesnt recognize the changes. For me i can cut 1 to 2 pounds a week for two weeks and then I have 4 week spreads on maintenance calories and repeat the cycle. It doesnt seem like much but you can lose 18 to 36 pounds of fat in a year this way. Thought id throw this in there in case it helps anyone. (youll have zero strength losses this way and no weight loss stalls)

[lee__d]

Ive found for me since I dont have tons to lose is to stagger out the cutting phases to the length that my body doesnt recognize the changes. For me i can cut 1 to 2 pounds a week for two weeks and then I have 4 week spreads on maintenance calories and repeat the cycle. It doesnt seem like much but you can lose 18 to 36 pounds of fat in a year this way. Thought id throw this in there in case it helps anyone. (youll have zero strength losses this way and no weight loss stalls)

This is a good strategy as well. Basically works out to having a very small deficit over a long time (in terms of weight loss, not metabolic effects ).

I know some people will complain that the weight loss might be too slow, but if you're not obese, slow eight loss is the way to go anyway.

[lee__d]

I see it ALL…THE…TIME! Metabolic damage and serious metabolic issues are rampant in the sport of bodybuilding. Metabolic damage is essentially a drastic slowing of the metabolism that is caused by excessive calorie restriction, excessive cardio, and stress on the body.

I think I can speak for all good prep coaches out there when I say that there is probably not much that is more frustrating than starting with a new client only to find that they have a completely crashed metabolism. To make matters worse I usually learn that they have been coached to that point by a previous trainer.

The reason this is so frustrating to me as a coach is because before this new client and I can even begin thinking about losing fat, we first must "fix" their metabolism. This is no easy task and can take months or even up to a year. So I am here to officially say, hours of cardio and cutting calories to ultra-low levels is not the way to get lean.

Female competitors are particularly plagued by this issue. Fat loss does not come as easily for the majority of women as it does for many men. As a result many will resort to drastic measures in an effort to get shredded.

Male or female, only the most motivated competitors are affected by this problem. The unmotivated competitor will give up long before things get to this level while those that are truly motivated will push through and do whatever it takes to get lean. The attitude of “whatever it takes” is common in this sport. Anyone that will do “whatever it takes” to win will not rule out starving themselves or doing several hours of cardio per day.

How A Slowing Metabolism Happens

Let me run you though a scenario with which I am sure many people are familiar. Let's say we have a competitor that is prepping for an upcoming bodybuilding show. Our competitor has put on a bit too much fat in the offseason, so being ready on time is going to be difficult. Since time is of the essence our competitor begins with aggressive cuts to his diet.

He was maintaining his body weight with about 3000 calories per day in the offseason, so he begins by cutting to 1600 calories and starts by doing an hour of cardio a day. This really gets things moving as he loses several pounds in the first few weeks. Eventually things begin to slow down though.

After a few more weeks fat loss has pretty much stalled, so our competitor, who is already eating very little, decides to cut out all carbs and lower his fat intake down to 20-30 grams per day. This gets things moving again but not nearly as fast as in the beginning. After another few weeks fat loss stops again. Since he really can't eat much less than he is currently eating, our competitor has no choice but to add another hour of cardio per day.

Fat loss barely crawls along for the next few weeks before it inevitably stops altogether. Our competitor is exhausted, has no energy to train, is eating no carbs, very little fat, and doing 2-3 hours of cardio per day, but the scale does not budge. There is still more fat he needs to lose, but our competitor is out of luck. His metabolism has stalled and it is not going to give up any more fat.

This is exactly the type of situation that leads to a huge metabolic slowdown and makes it nearly impossible to lose any fat. Now that we have identified how this situation occurs the big questions that remain are, why does it happen, and what can you do to prevent it?



Why A Slowing Metabolism Happens

Let’s clear one thing up right now. It is normal for the metabolism to slow down on any diet or calorie restriction. This is all due to metabolic adaptation. For a successful prep you need to understand how the body adapts to survive. The human body is an amazing adaptive machine that will always strive for homeostasis. Whatever conditions the body is put in, it will strive to survive within that new norm.

If you remember our bodybuilder in the previous example, he was eating 3000 calories a day to maintain his weight but he cut to 1600 to lose fat. As soon as he cuts calories his metabolism will begin to slow. Many people do not realize that the body uses calories just digesting and processing food. This is described as the thermic effect of food. So the simple act of eating less causes less energy output.

Once the body senses that fat loss is occurring it will begin to lower thyroid levels and diminish nervous system output in an effort to stop the weight loss. Once further calorie cuts are made and cardio is increased fat loss will resume again, but the body will further lower thyroid levels and nervous system output. It will also lower testosterone levels and raise cortisol levels, which will eventually lead to muscle loss. Since muscle is metabolically active tissue, meaning it requires calories simply to exist, the metabolism will drop even further.

So why does the body sabotage our effort like this? It is simple…survival. If the body did not make these changes it would be in serious trouble. If our bodybuilder eating 3000 calories a day cut his calories to 2500 per day and his body did not have these adaptive abilities, he would lose weight continually without stopping until he would eventually die. Luckily nobody is starving to death on 2500 calories per day (even though it may feel like it sometimes). So you see,these are normal adaptations that are necessary for survival.

Always remember that as soon as you make a change that will affect calorie intake or expenditure your body will immediately begin taking measures to reach homeostasis.

Metabolic Slowdown As A Cycle

From my experience, metabolism crashing is a cycle. People drive their metabolisms into the ground for their contest prep leading to a seriously slowed metabolism. Someone with a tanked metabolism cannot handle many calories at all. Yet after the show is over, most will tend to binge excessively as the months of restriction have now caught up with them mentally. Their metabolism is not equipped to handle this level of calorie intake and the fat gain is fast and furious. This leads to getting extremely heavy, yet the metabolism will remain depressed.

I have also found that most competitors that have prepped incorrectly to the point of having serious metabolic issues do not get lean enough. As a result many are not particularly pleased with their placing and are eager to get back on stage and redeem themselves. These competitors typically take little to no time off before prepping for another show. So they begin their prep with an already lowered metabolic rate, too much fat lose, and not enough time to lose it. The cycle begins all over again.

How To Prevent A Slowing Metabolism

Luckily there are several ways to prevent these serious metabolic issues from occurring. While the metabolism will slow a bit on any diet it does not and should not have to lead to extreme calorie deprivation and hours of cardio. Not only is this not healthy but in the end it will not get you lean enough. So here are the rules to follow for a better prep.

Tip #1 - Be Patient

Fat loss should not be rushed. You need to allow plenty of time to diet. You should aim to lose no more than 2 lbs. of fat per week and preferably keep a rate of 1-1.5 lbs. lost per week. This will ensure that muscle loss is minimized. Remember that muscle tissue is metabolically active meaning it uses calories just existing. This goes a long way toward keeping a healthy metabolism.

Another part of being patient is learning to make minor changes to the diet rather than massive cuts. Keep in mind that as soon as you make a change, whether it be cutting carbs or increasing cardio, your body will begin adapting to the change. Every change you are able to make to increase fat loss is a tool in your tool bag.

Do not use all of your tools in the first few weeks. If fat loss stalls and you cannot cut calories any lower and are already doing hours of cardio per day there are no more moves to be made. You need to save something up your sleeve for the end of the prep when you will need it.

Tip #2 - Keep The Carbohydrates

There is no denying that if you want to get lean you sometimes have to drop carbs to low levels. This does not mean that you should cut them out altogether though. Carbs increase cellular osmotic pressure (cellular hydration) and therefore cell volume.

When muscle cells are hydrated and have greater volume this sends signals to the body that it is in a fed state. The body, sensing it is in a fed state, then keeps the metabolic rate raised. Obviously if carbs are too high then fat loss cannot occur, but for continued fat loss carbs must remain in the diet.

Tip #3 - Utilize High Carb Days

Carbohydrates are essential to keeping an elevated metabolism and leptin is a primary reason for this. Leptin is a fat burning hormone that is directly related to carbohydrate intake and body fat levels (Romon et al, 1999). Leptin is a fat burning hormone that serves many functions, including the control of energy expenditure.

While we have already noted that to get truly lean carbs will eventually have to be lowered. As carbs get low and body fat levels dwindle the body will inevitably lower leptin levels. This can be combated to an extent by adding in high carb days. A high carb day once every 4-8 days can boost leptin levels since leptin is highly responsive to glucose metabolism.

Adding high carb days will not only boost leptin but it will lead to a more positive hormonal profile in general. Higher carb days can lead to higher levels of the thyroid hormone t3 as well as even keep testosterone levels elevated, which will further fat loss efforts.

Tip #4 - Don’t Cut Fat Too Low

Fatty acids are substrate for cholesterol, meaning that fatty acids must be available to create cholesterol which is eventually converted to testosterone. If fat intake is too low there will not be enough fatty acids available for optimal testosterone production. This will lead to lower testosterone levels. Low testosterone leads to greater muscle loss during prep, meaning a lower metabolic rate.

The body also has a built in adaptive response to chronically low dietary fat intake. When the body senses an extremely low intake of fat it will naturally try to hold on to body fat stores and fats are now at a premium. Taking in moderate amounts of fat will ensure that calories are low enough for fat loss, but the body does not perceive it as starvation......