DEXA Scan! (Read if you are thinking about doing it!)

CSARdiver

I work in a metabolics lab and have access to this and use this regularly. Not something I would spend a great deal on, but $75 is very reasonable. I also have a handheld impedance reader which is very accurate - within 1% of the DEXA. Note that all these machines are operator dependent and your accuracy increases with the routine you build.

lkpducky

What I find confusing is how to figure out muscle tissue gain. The scan tells you your LBM increase, but that would include water, glycogen, muscle, connective tissue, etc. I can't tell how much muscle tissue I gained from the before-and-after scans.

deannalfisher

Theo166 wrote: »

Think I'll save this for when I get closer to ideal body weight.
I already know I'm a fatbastard now, it's too early in my loss journey to help me set goal weight.

its never too early to set a goal - maybe it would be an intermediary goal - instead of 50lbs overall, you aim for 10lbs - but getting an assessment done at periodic intervals can help

deannalfisher

lkpducky wrote: »

What I find confusing is how to figure out muscle tissue gain. The scan tells you your LBM increase, but that would include water, glycogen, muscle, connective tissue, etc. I can't tell how much muscle tissue I gained from the before-and-after scans.

I had an inbody assessemtn done - not sure its accuracy as compared to Dexa, but on the results it gave me the following:
intra/extracellular water
dry lean mass
body fat mass

so by subtracting the intra/extra measurement from DLM, I could see the change

PAV8888

Necro thread @xchocolategirl

One of the things dexa scans do that is "different" is that they separately measure fat, bone and lean mass wheras many other measurements lump bone and lean mass into one. This is probably an only 6-8lb difference in terms of total lean mass, but I find it interesting when evaluating my protein goals.

Of course dexa is also susceptible to lean mass (usually inadvertent) manipulation.

If you carb load and/or eat a salty meal vs arrive fasted and glycogen depleted​ your total weight and fat % will change a bit because all that water will now be part of your lean mass on the day of the test.

This is true with other tests too; but it should be kept in mind when sometimes people get inconsistent results.

graphics1125

I've thought about doing a DEXA scan but my self esteem is to fragile.

macchiatto

Thanks for the info! That's actually a lot more affordable than I was assuming. I need to find out what the options are around here.

macchiatto

SCoil123 wrote: »

I got one once and it was an eye opener. My bf% was only a few % higher than calipers and measuring tape but it was enough to bump me up into the overweight category which was a motivator to get more proactive.

I really want to do it again. My goal is to get and stay at the 20-25%bf range.

Difference for me was 27-29% with calipers and measuring tape

32% with dexa

I had it done last year when I got seriois about getting back in shape.

Thanks for sharing your results, too.
I wonder if DEXA often ends up being higher than other methods or if it just depends on how the individual carries their weight.

sgt1372

macchiatto wrote: »

I wonder if DEXA often ends up being higher than other methods or if it just depends on how the individual carries their weight.

I have been measuring my BF/LBM quarterly for the past 6 months by both DXA scans and hydrostatic testing.

DXA is always higher than hydrostatic by about 3-4%. My last hydro test was 10.1% and my last DXA was 14%. 3 months before that the results were 12.1% hydro and 16.4% DXA. And, 3 months before that the results were 16.9% hydro and 20.3% DXA. A very consistent variation in the results.

trigden1991

lkpducky wrote: »

What I find confusing is how to figure out muscle tissue gain. The scan tells you your LBM increase, but that would include water, glycogen, muscle, connective tissue, etc. I can't tell how much muscle tissue I gained from the before-and-after scans.

Autopsy & disection

lkpducky

trigden1991 wrote: »

lkpducky wrote: »

What I find confusing is how to figure out muscle tissue gain. The scan tells you your LBM increase, but that would include water, glycogen, muscle, connective tissue, etc. I can't tell how much muscle tissue I gained from the before-and-after scans.

Autopsy & disection

They could remove some fat while they're at it

ninerbuff

alpepp wrote: »

I finally coughed up the money and got my DEXA scan done last Friday ($75 USD at my university). I decided to do it as I have been half-a$$edly working out and eating this past year. Well, it's time to put my money where my mouth is! I also just finished a personal training package (big strength gains, little physical results from poor eating) and am about to start a new package tomorrow. I also had wide varying measurements between the body fat scale, handheld device, and calipers. I wanted to know my accurate body fat so I can make a good judgment call on a goal weight and stop using BMI as my standard.

The results?

45.1% Body Fat (ouch!)

That makes me a 109 lbs of lean, mean body mass and an initial goal of 25% body fat between 140-145 lbs. That weight may end up being lower because, with over 60 lbs to lose, I may most likely lose some lean mass as I drop weight.

What I find funny/weird/awesome/frustrating is that, for my very short 5'1" frame, 140 lbs is still technically overweight according to the BMI chart, even if I should be within average limit for a woman by body fat %(almost to fitness level).

My personal trainer and I will be focusing mostly on fat loss and maintaining the muscle I have; therefore, I see lots of HIIT in my immediate future!

I am also going to the EM2WL approach a shot. My main problem with working out, especially with all the strength training I have done in the last year, is maintaining my energy consistently. This was pretty difficult to do on 1200 calories, even with eating back my exercise calories.

My plan is to have another DEXA scan done when I reach halfway between my current weight and goal weight (around 170 lbs) and then reevaluate my goal.

Thought I would post this for anybody considering it - the DEXA scan has been a great motivator for me. It helped me really evaluate what I want from my weight loss, work out, and my body in general.

Thoughts? Anybody else doing the same approach as me?

Just a quick note: HIIT isn't for FAT LOSS. That entirely depends on your calorie deficit. HIIT will help with your conditioning and fitness.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition

Cortelli

sgt1372 wrote: »

macchiatto wrote: »

I wonder if DEXA often ends up being higher than other methods or if it just depends on how the individual carries their weight.

I have been measuring my BF/LBM quarterly for the past 6 months by both DXA scans and hydrostatic testing.

DXA is always higher than hydrostatic by about 3-4%. My last hydro test was 10.1% and my last DXA was 14%. 3 months before that the results were 12.1% hydro and 16.4% DXA. And, 3 months before that the results were 16.9% hydro and 20.3% DXA. A very consistent variation in the results.

Interesting. I had a DXA and a Hydro done about 2 hours apart roughly 3 years ago, and my hydro and DXA BF% were within 0.7%. I haven't done any since, but may have to do so at some point just to see the results this time around.

Past experiment was here: http://community.myfitnesspal.com/en/discussion/1279724/round-3-dxa-versus-hydro-a-comparison#latest

Theo166

deannalfisher wrote: »

Theo166 wrote: »

Think I'll save this for when I get closer to ideal body weight.
I already know I'm a fatbastard now, it's too early in my loss journey to help me set goal weight.

its never too early to set a goal - maybe it would be an intermediary goal - instead of 50lbs overall, you aim for 10lbs - but getting an assessment done at periodic intervals can help

Looks like it's at least $125 in my area. I'd do it now if cheaper.

In 9 months I hope to be in the middle of my 'overweight' BMI range and more active in my exercise. At that point an accurate view of my BF and LBM will really help me target in on my goal weight.