Phase 2 - Causes of weight loss plateaus: Page 1
Metabolism:
Blame your success!  Yes, your success at losing weight may be the blame. It seems like every weight loss expert wants to tell you that as you lose fat you will crank up your metabolism into a better fat burner.  Actually, nothing could be further from the truth. 

1.  Less fat:  Realize the truth that the more weight you lose, the less fat you have to feed.  Consequently the amount of calories your body needs has lowered.  Therefore, as you lose weight, you need to lower your calorie intake.  That does not necessarily mean at this point you need to start counting calories, but rather try for a month to be more mindful of what you are eating and how much. 
2. Caring around extra weight will burn more calories as you exercise.  Pick up two weights and get on the tread mill.  You will notice that you will get tired quicker.  So less weight to carry equals fewer calories burned.

3. If you have been exercising your body is more efficient.  As you have exercised, your muscles have gotten stronger and require less effort to do the same tasks.  Therefore, fewer calories burned. For example, a man who was overweight by 100 pounds may have had a hard time walking up a single flight of steps without being totally out of breath.  After he loses 100 pounds, he can pick up two dumbbells totaling 100 pounds and carry them up the stairs with no exertion whatsoever.  Although his weight going up the stairs is the same, his muscular efficiency has been vastly approved. But this increase in efficacy means he has burned fewer calories than he did before.

Also, contrary to what many experts say, gaining a pound of muscle does not raise your metabolism by 40-60 calories per day.  That means 10 pounds would allow you to eat 400-600 calories more per day while doing nothing.  But in reality, fat uses around 2 calories per day and muscle only uses around 6. 

It should be noted that regardless of all the hype you hear, there are no magic metabolism boosting exercise techniques.  The best techniques only burn a few extra calories.  Added up over a long period of time they can be somewhat meaningful, but no silver bullet.

Even absolute killer rounds of HIIT (high intensity interval training) will only increase your metabolic boos 6-15%.  That means for 1000 calories burned on a tread mill, you are only increasing your post calorie burn 150 calories at very best (this is if you can perform and survive a 1000 calorie interval workout). If you are an elite athlete maybe, overweight and out of shape - it isn’t happening! 

Homeostasis:
90% of the time when someone is hitting a weight loss plateau, it is due to this major factor.  Your body’s metabolism has a process called homeostasis.  In a clinical sense, homeostasis is your body’s ability to resist changes and maintain the body in a normal state.  Concerning dieting, it does this by adjusting its energy expenditure.  It tries to maintain your body’s systems at a constant.

Practically, homeostasis is a survival process your body uses to keep itself functioning in the face of famine (or reduced calorie diets). Until our modern times when an overabundance of high calorie food has enabled the population to overeat, depleted caloric intake meant the person was in an area of famine. 

A person who cuts their calories too low may stop losing weight because their body is trying to maintain its current weight in the presence of lower calories.  This is to offset the starvation it perceives it has encountered.

Unfortunately if the calories are lowered to an extreme, the body will destroy muscle tissue and use it for energy.  This is the main reason low calorie and starvation diets are absolutely horrible for your body and result in such little weight loss.  So keep in mind, a moderate caloric reduction will trigger fat loss, a large caloric reduction will trigger your body to slow down its metabolism and allow muscle to be destroyed. 

Granted, homeostasis will keep you from losing weight only so long.  On a prolonged starvation diet you will continue to lose weight, but it will cause severe damage to your body.  Besides, if you go back to your old eating habits again after starving off the weight, you will pack on the pounds faster than ever before as your body responds to having been starved.

Keep in mind, with any good diet you need to make sure the calories you do consume have enough of the right nutrients to maintain your body. Even on a non-calorie restricted diet, if you don’t have enough protein in your diet, muscle tissue will become damaged and unable to adequately repair itself (especially if you are doing intense exercise).  Simply having enough calories does not mean your body is getting what it needs to for proper health.

Next: Phase 2 The big picture:


Quote:
Homeostasis is your body’s ability to resist changes and maintain the body in a normal state.  Practically, it is a survival process your body uses to keep itself functioning in the face of famine (or reduced calorie diets).
Quote:
A moderate caloric reduction will trigger fat loss, a large caloric reduction will trigger your body to slow down its metabolism and allow muscle to be destroyed. 
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