Preventing Muscle loss while dieting.

zachborg1

This is probably one of the most debated topic. I've seen multiple arguments opposing each other and this just confuses me. My question is: When does the body start using muscle as a source of energy? What factors affect this? (ex. calorie intake, calorie deficit, cardiovascular/strength training?).

usmcmp

There's not a definitive point where the body uses lean mass, it's a combination of factors. These factors are:

-Leanness: the less body fat you have the more likely you are to lose lean mass.
-Magnitude of deficit: the greater the deficit the greater the risk.
-Protein consumption: eating adequate protein is the easiest way to mitigate risk.
-Resistance training: use it or lose it essentially.
-Age/hormones: various factors here play into your ability to maintain lean mass and lose fat.

NorthCascades

I don't think it's so much that your body uses muscle for energy, because that's terribly inefficient and there are better alternatives most of the time. It's that it'll break some muscle down for the raw materials they're made of, amino acids.

Smaller deficit (slower weight loss), higher protein diet, and resistance training are the levers you can pull to affect this.

Cardiovascular exercise has nothing to do with it, except that it burns calories, which contributes to a deficit.

cwolfman13

NorthCascades wrote: »

I don't think it's so much that your body uses muscle for energy, because that's terribly inefficient and there are better alternatives most of the time. It's that it'll break some muscle down for the raw materials they're made of, amino acids.

Smaller deficit (slower weight loss), higher protein diet, and resistance training are the levers you can pull to affect this.

Cardiovascular exercise has nothing to do with it, except that it burns calories, which contributes to a deficit.

Pretty much...

Also, muscle is an expensive commodity from an energy standpoint for the body to maintain, so it's a use it or lose it proposition...if you're not using it, there's not need for your body to maintain that kind of expensive commodity.

lcrepp

Keeping protein at 1g per body weight in lbs is ideal to hold onto as much muscle as possible while in a deficit. Continue to train the same as if you were not in a deficit. Maintain weight on the bar, progressive overload.

Keep protein on the higher end of the suggested 0.8-1.2 grams is what will keep your body from using it as fuel. There may be a small percentage that gets used, but this happens when you are in the lower body fat percentage.

usmcmp

Since you posted multiple threads I am copying my answer here:

There's not a definitive point where the body uses lean mass, it's a combination of factors. These factors are:

-Leanness: the less body fat you have the more likely you are to lose lean mass.
-Magnitude of deficit: the greater the deficit the greater the risk.
-Protein consumption: eating adequate protein is the easiest way to mitigate risk.
-Resistance training: use it or lose it essentially.
-Age/hormones: various factors here play into your ability to maintain lean mass and lose fat.

Lizzypb88

zachborg1 wrote: »

This is probably one of the most debated topic. I've seen multiple arguments opposing each other and this just confuses me. My question is: When does the body start using muscle as a source of energy? What factors affect this? (ex. calorie intake, calorie deficit, cardiovascular/strength training?).

My mom had weight loss surgery, and a year after losing the weight, she got hip pain... basically the dr told her that she lost a lot of muscle along with fat, and the big loss in muscle was causing her pain, and was told to exercise
From what I've always understood, you have to lightly exercise, some who lose weight and are sendentary will lose much more muscle mass compared to those who exercise. Key is exercise, even light walking

zachborg1

Thank you all for such detailed answers!

zachborg1

usmcmp wrote: »

There's not a definitive point where the body uses lean mass, it's a combination of factors. These factors are:

-Leanness: the less body fat you have the more likely you are to lose lean mass.
-Magnitude of deficit: the greater the deficit the greater the risk.
-Protein consumption: eating adequate protein is the easiest way to mitigate risk.
-Resistance training: use it or lose it essentially.
-Age/hormones: various factors here play into your ability to maintain lean mass and lose fat.

Any ideas how much the calorie deficit range should be so as to keep muscle loss minimal?

jennybearlv

I'm not sure if there is an answer to exactly how many calories will prevent muscle loss. If you have been lifting weights regularly it is pretty easy to tell if you are gaining or losing muscle because your level of strength will change on the lifts you do regularly. Keep track of your exercise in a journal or your phone, you can even make charts and plot trends to see where things are going.

For example I was eating at a 1000 calorie deficit and my strength kept decreasing, so I know I was losing muscle along with the fat. I was morbidly obese, so more concerned about losing weight than just fat. I've been slacking off on my tracking for the past few weeks, maintaining to gaining slightly according to the scale, and now my lifts are going back up. I'm not sure what my magic number is, but I think it's pretty close to maintenance unfortunately.

usmcmp

zachborg1 wrote: »

usmcmp wrote: »

There's not a definitive point where the body uses lean mass, it's a combination of factors. These factors are:

-Leanness: the less body fat you have the more likely you are to lose lean mass.
-Magnitude of deficit: the greater the deficit the greater the risk.
-Protein consumption: eating adequate protein is the easiest way to mitigate risk.
-Resistance training: use it or lose it essentially.
-Age/hormones: various factors here play into your ability to maintain lean mass and lose fat.

Any ideas how much the calorie deficit range should be so as to keep muscle loss minimal?

There's not an exact amount, but a frequent suggestion is 20% below your total daily energy expenditure. Morbidly obese can have a greater deficit without compromising lean mass and people within the athletic range may need a smaller deficit.