when does a calorie defecit burn fat and not muscle

[solstice]

I have hit a plateau and my bodyfat has gone up. I workout 1 - 2 hours, including strength training, and perhaps all this effort has gone to eat away muscle. When does fat get burned instead of muscle ?

[Dodger]

As long as you get plenty of fat/protein in your diet, your body will not be using muscles for energy. Hard exercise does 'damage' muscles. They rebuild during the rest periods. The harder the workout, the longer the rest periods should be.

[kbfunTH]

How do you know you're losing muscle and your bodyfat is going up?

Optimum muscle stimulation is equally as important as optimum protein intake. These get more critical the leaner you get. You might want to analyze your program and make some adjustments.

[watcher16]

Just take 300-500 max as calorie deficit. For women I think 300 is the maybe even the maximum.

Otherwise you will burn muscle.

[medalian1]

Deficit ... so wait, what is the lowest # of calories a typical male can consume per day and not cause muscle loss? I'm trying to gain muscle and lose fat, but ~ 2500 calories per day my weight doesn't change. Bringing it down to 1500 calories per day I notice weight loss, but I just hope I'm not losing muscle too!

-edit-

I'm consuming 150-200g of protein per day still (weight 222lb). I can't imagine having more than that without reaching over 3000 calories per day. I think I understand now how they have to bulk/cut in order to get big.

[kbfunTH]

Deficit ... so wait, what is the lowest # of calories a typical male can consume per day and not cause muscle loss?...

That is the billion-dollar question. Most people are not able to pull this off simultaneously. Protein intake, diet composition and optimum strength training and genetics are the keys.

Your protein intake is probably adequate, but upping it to match your bodyweight may have better results. This may require a little less fat and/or carbs in order to keep your calories from exceeding your maximum limit. If dropping those two isn't feasible, then you'll have to up your activity outside of strength training. One great way to do this is high rep circuit/interval training.

I little muscle loss during dieting is generally acceptable. This really has more to do with how lean you already are and your level of conditioning.

[nets33]

Great e-book I'd recommend is Burn the Fat, Feed the Muscle . It provides a great background on burning fat vs. building muscle. I'm still working my way through it but it has already helped me better understand how I can improve my working out and weight loss plan.

kbfun is exactly right.. you cannot burn fat and build muscle at the same time. If your goal is to lose fat then you want to eat a calorie deficit... but note that Women should go no lower than 1,200 a day and men 1,800. This is your "survival" calorie level. Anything below this and your body will hang onto it's fat reserves and begin using muscle as energy - you've entered starvation mode.

What you need to do is determine how may calories you need to sustain your weight based upon your current stats (height, weight, age) and your activity level. Once you know that number then it is best to go 500 to 1,000 less than your maintenance level, never going below the "survival" calories listed above.

A 500 caloire deficit over seven days equates to 3,500 calories or 1 pound of fat loss... to maintain your muscle you must exercise and eat correctly. Any more than 1 to 2 pounds a week and you are probably taking off muscle as well as fat.

I did this calculation for myself and found that for weight loss I should be eating 1,800 to 2,000 calories a day. And I have begun to see a weight loss again. It does work!

If you can get your hands on the book I highly recommend it. :)
Kiks

[kaypeeoh]

My understanding is the body does not want to waste protein. Ingested protein is broken down into amino acids which are absorbed into the blood. These are used to repair injured muscle as well as maintaining the body's stores of protein.

If you ingest more protein than the body needs, the excess is de-aminated and used for energy. If the energy needs have been met what's left over is added to the fat storage. So too much protein could prevent weight loss.

Using figures from Barry Sears Zone Diet, you need a minimum of 0.5 grams of protein per pound of lean body mass. Heavy exercisers need up to 1.0 grams of protein per pound of lean body mass. Lean body mass is what you weigh once you've subracted the weight of your fat. E.G., if you weigh 100 pounds but have 20% body fat, your lean body mass is 80 pounds.

It's important to not eat more protein than you need. According to Sears, excess protein stimulates insulin which stops fat burning.