Friday, April 01, 2011
My own personal philosophy is to
1) get the BMI below 30, and then
2) focus on dropping body fat.
The problem is, how do you actually *measure* body fat? It's elusive.
Here's a nice synopsis on Wikipedia:
Here's an interactive web tutorial on some methods:
(Calipers aren't mentioned in this one.)
Leigh Peele wrote a very nice post about the topic:
The pictures in there are especially helpful.
James Krieger wrote a really really in-depth series of 7 columns about the relative pros and cons of different methods for figuring out % body fat:
The Pitfalls of Body Fat Measurementť: Part 1
The Pitfalls of Body Fat Measurement: Part 2
"The bottom line is that underwater weighing can give good results when looking at group averages, but not so good results when looking at individuals. The sad thing is that underwater weighing is actually the best method out of the 2-compartment models. Other methods, including the Bod Pod, BIA, and skinfolds, are significantly worse."
The Pitfalls of Body Fat Measurement, Part 3: Bod Pod
"The Bod Pod does OK when looking at group averages, with some studies showing error rates of around 2%; however, other studies have indicated average error rates of over 5%. The individual error rate for the Bod Pod can be unacceptably high in some individuals, and the Bod Pod is horrible for tracking change over time. For these reasons I would recommend against using the Bod Pod as a body composition assessment tool. Hydrostatic weighing, despite some of its problems, is much more reliable."
BIOELECTRICAL IMPEDANCE (BIA)
The Pitfalls of Bodyfat Measurement, Part 4: Bioelectrical Impedance (BIA)
"BIA can be problematic because itâ€™s a prediction based off of a prediction, so the error gets compounded. When you look at group averages for BIA measurements, there tends to be bias, with BIA often underpredicting how much fat you have. As with other techniques, the individual error rates can get high, with some research showing error rates of around 8-9%. In fact, BIA doesnâ€™t do much better than BMI at predicting body fat in some cases. When it comes to measuring change over time, BIA can often underpredict the amount of fat loss, and the estimated change can be off by up to 8%.
For all of these reasons, I am not a fan of BIA for measuring body composition in individuals. If you are going to use BIA for tracking body composition over time, I recommend very long time intervals between measurements (at least 3 months, but 6 months is probably better), as the error rate for BIA can be larger than the changes in body fat in you see. Whatever numbers you do get using BIA, always remember they are very rough predictionsâ€¦.and I emphasize very rough."
The Pitfalls of Body Fat Measurement, Part 5: Skinfolds
"Like BIA, skinfolds can be way off when it comes to determining body fat percentage in individuals. When it comes to tracking change over time in groups, then skinfolds do pretty well. However, errors for tracking change in individuals over time can be up to 3-5%. Thus, if you are going to use skinfolds for tracking a single person over time, I recommend very long time intervals between measurements (minimum of 3 months but 6 months is better); otherwise, the error rate is higher than the change that you can see. In fact, I recommend against even calculating a body fat percentage. If skinfold thicknesses are going down, then you are likely losing fat."
DUAL-ENERGY X-RAY ABSORBANCE (DXA / DEXA)
The Pitfalls of Body Fat â€śMeasurementť, Part 6: Dual-Energy X-Ray
"Despite the fact that DEXA represents a 3-compartment model, its error rates are no better than hydrostatic weighing, and in some cases is worse. Like other techniques, DEXA does well when looking at group averages, but not so well when looking at individuals. Individual error rates tend to hover around 5%, although some studies have shown error rates as high as 10%. When looking at change over time in individuals, error rates have hovered around 5% in some research, although other research has indicated DEXA to perform much more poorly. For these reasons, I do not recommend DEXA for tracking change over time in individuals. If you do use DEXA for tracking change over time, I recommend very long time periods between measurements (a minimum of 3-6 months), as you will need a minimum of a 5% change in body fat to reliably detect a true change in body fat in most people."
The Pitfalls of Body Fat Measurement, The Final Chapter
"Body fat testing isnâ€™t useless, but you do need to be careful in how you interpret the results." "For extremely obese people, I recommend simple body weight and circumference measurements."
According to him, hydrostatic weighing (NOT Bod Pod) and DXA are the most accurate. For following trends in % body fat he recommends calipers or if you're extremely obese, a plain old measuring tape.
For those of us who have weighed over 300 lbs, our bones are likely to be extremely dense (we're weight-lifting all the time just by walking around), so DXA is probably a better bet than hydrostatic weighing if you want to go either of those routes. I had a DXA scan done Jan '10 and at that point they said my bones were 25% denser than average.
I checked my Tanita BIA scale against the DXA % body fat measurement and discovered that if the scale was set to "athlete" mode the readings matched exactly.
So for now I'm just going with what my scale says, although BIA is not supposed to be very accurate. I'm averaging the daily measurements over at physicsdiet.com.
Although DXA is the technology used on the Biggest Loser to assess % body fat, many people still do not know about it. Here is a nice PDF article by Mary Oates summarizing its use, with pictures:
So, where can you get a DXA scan done?
If you live west of the Continental Divide you can probably find a sports medicine or wellness center that will do it, if you just use Google Maps and search for "DXA" and "DEXA."
If you live in the East, it seems to generally be a bit trickier. You'll need to contact the radiology or imaging departments at a few local hospitals to find out if they 1) have the right machines (GE Lunar or Hologic) and 2) if they will even do a whole body scan (many places just use DXA for bone density testing and either don't know they can or don't choose to provide whole body composition analyses).
Once you've found a place that knows what you are talking about, you can bring the above Oats PDF article to your physician and ask for an order for the scan.
There aren't any lists anywhere of facilities that provide DXA body composition analysis, so I've started compiling one. The list of places that have responded so far is here:
If you know of a place that does it, or any lists where people collect that kind of information, please have them fill out this form here, so we can find more places:
Tuesday, March 29, 2011
The one really important joint for kayaking is the shoulder. The one thing you don't want to mess up is your rotator cuff.
Guess what I hurt when I fell snowboarding on Sunday? Yeah.
^%$#@!! off-season sports.
Doc says to stay off it 8-10 days and if it's not better by then to get an MRI.
Which means I won't be going to West Virginia to paddle this weekend as I'd planned.
So now I get to satisfy myself with indoor cycling. Weight lifting is going to be kind of out, until the shoulder is better. Except for stuff I can do with my left hand I suppose. I'll ask my PT when I see him tomorrow.
Thursday, March 17, 2011
So I joined a study as a research subject. It's kind of cool.
They lent me an Android phone for a month and I'm supposed to take a photograph whenever I make a health-related decision, rate it on a scale of -3 to +3, associate an emotion with it, and share it with the other people in the study who are also doing the same thing.
Then we can look at each other's photos and comment on them and have conversations.
Here's the page where the research study is described:
Look at the list of projects on the lower left and click "Vera."
If you don't feel like following the link, here's the blurb about the study:
"A key to behavior change is the ability to intervene at the point of decision. In health behavior, this could be the moment one must decide between taking the elevator or the stairs or whether or not to eat a piece of cake. These are also the moments where it is most difficult to reach people--they occur throughout the day, often randomly, in any location. Fortunately, the ubiquity and awareness of today's mobile phones provides us with a solution. The goal of this project is to explore the use of the mobile phone as a behavioral interrupt: how, at the point of health-related decisions, can we encourage people to take a moment to think about the ramifications of their decision, reflect on past decisions, and ultimately make healthier choices?"
So far I've only had one conversation with someone who posted a picture of her dog (I commented that I thought it looked cute and she said thanks).
It kind of reminds me of the blogs WOLFKITTY was doing for a while where she logged all her food by photograph.
I'm interested to see if it'll help me stay on track, because it often is at the moment of decision that I waver and sometimes end up making choices I regret - especially when it comes to binge eating. I'll let you know how it goes.
It's also kind of neat to have access to a smart phone. My cheapo Tracfone can't do these things. I think I prefer the iPod interface to Android overall, but I could get used to the swipe text entry feature...
Wednesday, March 16, 2011
Inspired by another blog post to share some of my current eating habits.
I frequently buy the big family pack of boneless chicken breasts from Wegmans ($1.99/lb), and with kitchen scissors trim off the remaining bits of fat (those go in a container in the fridge for cat treats). As far as I can tell, Wegmans does not inject this chicken with extra saline.
Then I chop up the breasts with the scissors into manageable pieces and freeze them, in handfuls of pieces, in ziploc bags.
To use I dump the frozen raw chicken pieces into a microwave bowl with some water and cook 'em. Usually it takes about 3 minutes on high, then I poke them apart and cook for 3 more, often adding a can of "Light" soup (Campbell's and Progresso both make soups which have about 150 - 200 calories per can.) Or I just add actual vegetables and seasonings and make soup from scratch. If I have the time I lengthen the second cooking time to 10 or 15 minutes on medium power. The flavor is better and there is less risk of boiling over.
I like to buy these packages of salmon and keep 'em in the freezer. They're individually wrapped, which is convenient. I take one out when I arrive at work and it's usually thawed by lunchtime.
Then I fire up the toaster oven, spread foil on the tray, spray with some olive oil,
sprinkle salt-free lemon pepper, slap that fish on top, sprinkle with more lemon pepper, and broil for 5-10 minutes.
You can do the same thing with shrimp and you don't even have to thaw them first, although I sometimes do. You can also add shrimp to soups. It's one of the lowest-calorie lean protein sources out there.
Sometimes I just microwave the shrimp, stopping every few minutes to dump out the water and move the cold ones in the center to the outside.
Then I dip in Tabasco sauce as I eat them.
I also buy giant Hubbard squash (anywhere from 1-5 dollars each), drop them from chest height on the front stoop to break 'em open, scoop out the seeds, and bake skin-side down for about 3 hours at 350. The seeds go into the bird feeder where the blue jays enjoy them.
Sometimes I rinse the seeds and bake sprinkled with salt-free seasoning. It depends on how ambitious I feel and whether I want a high calorie snack sitting around or not.
When a fork goes in easily and there are lots of nice carmelized edges I scoop the flesh into microwave and freezer friendly containers and freeze them. One squash often yields more than 16 cups of actual food. I think the flavor is superior to other kinds such as butternut.
Then I microwave with seasonings (any kind of alt-free one works) or add a dollop to the chicken soup, above.
Sometimes for dessert I just take the squash cold, add some nutmeg and cinnamon and sugar substitute and mix it up. It tastes like pumpkin pie.
P.S. The absolute best tasting squash, in my opinion, is Buttercup.
I didn't mention it above because Hubbard is so much cheaper and tastes almost as good. I bake it the same way, but because it's smaller it takes more like 1-2 hours. They're small enough you can cut them open with a knife. Sometimes I'll bake half of one in the toaster oven for lunch. (No one else uses the toaster oven at work between breakfast and lunch so it's available.)
It was bred in North Dakota to replace sweet potatoes which don't grow there because it's too cold:
Yeager, A.F. and E. Latzke. Buttercup Squash: Its Origin and Use. Fargo, ND: Agricultural Experiment Station, North Dakota Agricultural College, 1932. Bulletin/North Dakota Agricultural Experiment Station no. 258. 19 p. NAL 100 N813 no.258
In 1922 North Dakota researchers Yeager and Latzke undertook a squash breeding program that was initially focused on the Hubbard squash. Their aim was to develop a desirable variety that would take the place of the sweet potato, which had proved unsatisfactory in variety testing in the region. This report, issued ten years hence, describes the origin of the Buttercup variety, a small turban-shaped squash selected from an accidental cross of Quality and Essex Hybrid, and also considers growing methods and the varietyâ€™s cooking and food qualities. A good portion of the bulletin consists of general instructions for cooking and several dozen recipes (p. 13-19). With black-and-white photos, and bibliography (sources cited in footnotes).
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