Starvation mode with too much exercise?

AshLittle1 wrote: »

I just came across an article from the Oxford Journal. Basically there is a metabolic adaptation that takes place with severe caloric reduction, 1000-1200 calories consumed per day but exercise reduces the effect of the metabolic adaptation. I am still having trouble finding out information about, at what level of caloric restriction does metabolic adaptation start taking place?

http://fampra.oxfordjournals.org/content/16/2/196.full

I think each person is different based on a whole host of other variables....
Total BF
exercise
age
health
etc.....

So there is no "Hey this is when your adaptation happens your metabolism slows down"

Again, like I said earlier....Your body responds and adapts based on a whole host of variables.....
Our bodies are very smart at doing its number one job....preserving life.

OP, here's a discussion of the study I referred to:

http://www.myfitnesspal.com/blog/heybales/view/reduced-metabolism-tdee-beyond-expected-from-weight-loss-616251

People get sensitive about the term "starvation mode" because it gets used improperly all the time, to mean that you will stop losing weight. That's not true, but I think there's evidence that it can affect metabolism more than simply losing weight and that part of that is avoidable, and also having too aggressive a deficit might affect energy (which will result in a lower TDEE) or cause increased loss of muscle mass, so there are good reasons not to be too aggressive.

What being too aggressive is depends in part on how much you have to lose.

What matters isn't your BMR, but your TDEE, and most people won't want to go more than 1000 below their TDEE, with a lower amount (more like 500 or, say 20%) if you have less to lose and even less if you are close to goal and worried about keeping as much muscle as possible.

MFP's general plan of adding more calories as you exercise more is consistent with that, but many of us only eat back part of those calories since the amounts sometimes seem too large.

What made sense to me was just to watch how much I was losing over a month and adjust.

astralpictures wrote: »

AshLittle1 wrote: »

So, if my BMR is 2600 a day and myfitnesspal wants me to consume 2000 calories a day with 600 calories of exercise, I do not need to worry about my metabolism slowing down over time correct?

Your metabolism WILL slow down over time if you lose weight, but you don't need to worry about it. It's natural and not preventable since there will be less of you to carry out your normal functions, your body will need less energy.

However I also believe that people's TDEE does suffer if they eat too little, which can lower their calorie maintenance level. If you are severely under-eating, your body will respond by feeling both physically and mentally sluggish. You won't have adequate energy intake or nutrition, which could result in medical issues. Therefore, your body's defense will to make you feel exhausted, and you won't move around as much. This lack of fuel will then lower your TDEE as you just won't feel up to doing physical activities with the same strength you once did. This is not "starvation mode," because your metabolism won't suddenly quit (except for death), and you will still lose weight because no magical internal process will decide to store fat instead of burn it while in deficit. But you will feel crappy. That's why people generally tell others to eat more if they're eating a low amount of calories.

lemurcat12 wrote: »

OP, here's a discussion of the study I referred to:

http://www.myfitnesspal.com/blog/heybales/view/reduced-metabolism-tdee-beyond-expected-from-weight-loss-616251

People get sensitive about the term "starvation mode" because it gets used improperly all the time, to mean that you will stop losing weight. That's not true, but I think there's evidence that it can affect metabolism more than simply losing weight and that part of that is avoidable, and also having too aggressive a deficit might affect energy (which will result in a lower TDEE) or cause increased loss of muscle mass, so there are good reasons not to be too aggressive.

What being too aggressive is depends in part on how much you have to lose.

What matters isn't your BMR, but your TDEE, and most people won't want to go more than 1000 below their TDEE, with a lower amount (more like 500 or, say 20%) if you have less to lose and even less if you are close to goal and worried about keeping as much muscle as possible.

MFP's general plan of adding more calories as you exercise more is consistent with that, but many of us only eat back part of those calories since the amounts sometimes seem too large.

What made sense to me was just to watch how much I was losing over a month and adjust.

If you lose weight and part of that weight is muscle, then yes, your Energy needs will drop as well.
That is why most people on here recommend weight lifting while losing weight.
It keeps your energy requirements high.

Body fat does not require energy to maintain, it is purely a store of energy.
Muscle however does require energy to maintain.

So when losing weight, your should prioritize maintaining as much muscle as possible during the process.

If you let your calories drop beyond a certain point for a certain amount of time, your metabolism shuts down. I was wondering, if I keep my calories at a healthy level but do a lot of cardio and weight training, burning enough calories to put me at a low net calorie count for the day, will my body enter its starvation mode and slow my metabolism?

"Starvation Mode" gets batted around here a lot.

Generally speaking, you will not do damage to your metabolism until you get down into true starvation ranges of body fat - like single digit percentages.

However, when you lose body fat your Leptin levels drop, and when that happens your body responds by making skeletal muscle operate about 20% more efficiently. This results in about a 10%-15% reduction in overall metabolism.

This is not "starvation mode", it is called "Adaptive Thermogenesis". This has been seen in the laboratory under controlled circumstances for weeks and has been extrapolated out to persist for years.

The result is that someone who was once obese and lost weight will have a metabolism that is 10%-15% less than someone of the same body composition who was never obese. This equates to 200-300 fewer calories that will be needed for weight maintenance.

So will your metabolism slow as a result of fat loss? Yes, about 10%-15%. But it is a response to fat loss, not calorie restriction.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3673773/

maillemaker wrote: »

If you let your calories drop beyond a certain point for a certain amount of time, your metabolism shuts down. I was wondering, if I keep my calories at a healthy level but do a lot of cardio and weight training, burning enough calories to put me at a low net calorie count for the day, will my body enter its starvation mode and slow my metabolism?

"Starvation Mode" gets batted around here a lot.

Generally speaking, you will not do damage to your metabolism until you get down into true starvation ranges of body fat - like single digit percentages.

However, when you lose body fat your Leptin levels drop, and when that happens your body responds by making skeletal muscle operate about 20% more efficiently. This results in about a 10%-15% reduction in overall metabolism.

This is not "starvation mode", it is called "Adaptive Thermogenesis". This has been seen in the laboratory under controlled circumstances for weeks and has been extrapolated out to persist for years.

The result is that someone who was once obese and lost weight will have a metabolism that is 10%-15% less than someone of the same body composition who was never obese. This equates to 200-300 fewer calories that will be needed for weight maintenance.

So will your metabolism slow as a result of fat loss? Yes, about 10%-15%. But it is a response to fat loss, not calorie restriction.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3673773/

Please find me a study where Leibel didn't draw his data from patients who had lost weight on DRASTICALLY low calorie intakes.

senecarr wrote: »

http://www.bodyrecomposition.com/fat-loss/permanent-metabolic-damage-followup-qa.html/

Good read.

Take note of the last Q&A on that page.

I think a lot of people do this....
"Oh I only eat 1200 calories/day (honest). And cannot lose weight"