Tuesday, March 08, 2005

Fit, Fat, and Thermodynamics

Warbs has a post up about why we're so fat as a nation. His basic idea is that, aside from being sedentary, we have a problem with portion control:

"In most of Europe, the dinner meal is a long process. American culture has long been one that is always on the move, always racing to finish a meal to get on to other things, and has never understood why those Europeans would want to sit down for a 3-hour dinner.

Bear with me a moment here. Think back to when the American hustling car-culture took hold. People were always in a rush, always in a hurry to finish meals. As such, we would consume our food in a very short period of time. Since the body takes a while to feel the effects of being "full", it was often that people were done with their meal before that feeling set in. Thus, restaurants worked hard to provide bigger and bigger portions (and American's wealth, another consequence of the GO!GO!GO! culture, easily financed this), such that people would never finish their meal and still feel hungry.

What happened next is no surprise. People would overeat and stuff themselves on a single meal, consuming far more calories in one meal than their body would ever need. This grew into our culture, and we continued to just grow accustomed to large portions. The large portions offered no reason not to continue eating too much, and now we're all fat as pigs."
He certainly has a point here, and it's not just related to cultural habits, or to the psychology and physiology of appetite; it's just as (if not more) related to basic physics.

The cultural ideas about our meals, menus, and portions were all set while Americans, on average, were expending from 2400 to 3200 calories per day, often in hard physical labor.

It takes 16-24 calories per day, per lean mass pound; and 6-8 calories per day, per fatty mass pound, at "room temperature" to keep lean body mass at 98 degrees. For most people this averages out to about 11 calories per pound per day, just to maintain their body temperature, to breathe, and to keep their heart pumping (oh and yes, that means most people have WAAY too much fatty mass).

These days the average American is primarily sedentary, and expends from 1600-2400 calories per day just sitting still and walking around. Unfortunately that is really just about all most of us do.

That extra 800 or so calories per day add up to somewhere between half a pound, and a pound a week in extra body weight, until your calorie consumption is balanced out by your extra calorie expenditure from the weight gain, some 60-70lbs down the line.

This is coming from a guy who weighs 365lbs, and who at his lightest was 265-285 at 7%-12% bodyfat. I maintained 265-285 from the time I was 13 (when I stopped growing), til I was 23.

The difference? I expended 3500-5000 calories per day for 8 years, then I had a severe knee injury and didn't walk more than 6 feet without a cane for six months. I gained 60lbs of straight fat, and lost a lot of muscle in that time (which of course was replaced by, more fat). That was 5 years ago, and the lowest I've been down to since is 295, about a year ago, and of course that was without gaining back all that muscle mass.

I'm a guy who can lose 20 lbs in a week if I work at it, and maybe 40lbs in a month without much difficulty. I can even lose 10lbs in a single day if I excercise a lot, but most of that will just be excess water, and I'm talking about losing real weight at that point, not just water weight. Just about everyone who isn't a professional athlete, dancer, or bodybuilder carries between 5% and 15% of their body weight as extra water, over and above their actual weight. When people see one or two pounds variation in a day, thats almost all water.

By the way, just about anyone can lose that much, at least in percentage terms, if they REALLY work at it, but it's a bit easier for me because of my muscle mass. Remember, that's only 10 percent of my bodyweight, which most people can lose in one month if they work at it (though doctors recommend you dont lose more than 5% a month).

Also remember, the bigger you are to start with, the faster your initial weight loss will be. If you limit your intake, and excercise properly, this will work for about three months, during which time you can lose from 10-20% of your bodyweight. Yes I said you could lose that much in a month, but it takes hard work, and your weight loss will slow down qick after the first 10%.

After that first three months, you need to do more. You'll probably need to take vitamin and other nutritional supplements, and you'll need to focus your excecise and your diet more, but really it still just comes down to basic physics.

The "secret" to maintaining or losing weight? Thermodynamics. Eat whatever the hell you want, so long as you burn as much, or more calories than you eat. In terms of bodyweight, your body can't tell the difference between eating 1lb of fat (3500 calories) and 2lb of sugar (about 3500 calories).

Now importantly, this is just about weight, not health. Obviously eating 1 lb of fat per day is a BAD thing for your heart. It's also not about muscle, because you need to balance your fat and protein intake or you're going to lose lean mass, which you want to keep, instead of fatty mass.

In my case, because of my muscle structure (pretty damned massive), I tend to actually gain weight to start as I work out, because I gain lean muscle mass very rapidly, and lean muscle mass weighs 1.7 times as much as fat.

If you manage it properly you can lose fat, and gain muscle at the same time; and the more muscle you gain, the more fat you lose, and the faster you lose it (remember that difference between calorie expenditure for fatty mass and lean mass).

Oh and apropos of nothing whatsoever, you may not lose weight right away, but you will get stronger, faster, better looking and healthier, which is really why most of us want to "lose weight" anyway.

Now, entirely contradicting everything I just wrote, try out some of these Recipes for REAL men.