Optimum fat levels

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mikesbytes
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Optimum fat levels

Postby mikesbytes » Tue Oct 22, 2013 9:49 am

The obesity crisis is well known and many who have found themselves in this situation have turned it around with smarter eating and exercise.

However at what point do we stop the reduction of fat levels? There seems to be a number of ways to look at it;
Measurement metods
- BMI. This may be fine to use when loosing a large quantity of excess, but its accuracy isn't there when you approach the finish as there are too many assumptions in the calculation
- Hip to Waist ratio and other calculators. A step up from BMI but still not perfect. May be useful for individuals as long as you don't compare with others as each of us holds the fat a little differently to others.
- Water displacement to weight ratio. You need a tank where you can accurately measure the water displacement when you get in. Fat takes more space than muscle for the same weight.
- DEXA scan. Understand that this will give about as accurate as it gets and can even separate between fat around the vital organs and external fat. One for those who really want to know.

Levels
- Seems to be always quoted as a % of total body weight. I've wondered if a better measurement would be kilo's of fat compared to your height and gender.
- Healthy range. A figure between minimum and max recommendation. If there any health difference within the range? Should we be smack in the middle
- Minimum level. Sport and Figure competitors will often want as little fat as possible, so to enhance their competition objectives. From a health viewpoint is this OK, or is it bad?
If the R-1 rule is broken, what happens to N+1?

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casual_cyclist
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Re: Optimum fat levels

Postby casual_cyclist » Wed Oct 30, 2013 7:31 pm

weightology weekly did a great round up of Body Fat mesurement. I had no idea that Body fat testing is a prediction, not a measurement.

http://weightology.net/weightologyweekly/?page_id=146
http://weightology.net/weightologyweekly/?page_id=162
http://weightology.net/weightologyweekly/?page_id=175
http://weightology.net/weightologyweekly/?page_id=218
http://weightology.net/weightologyweekly/?page_id=250
http://weightology.net/weightologyweekly/?page_id=260
http://weightology.net/weightologyweekly/?page_id=283

Of particular interest with regard to the above:
DEXA: The Verdict

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.
and
You don’t need to have your body fat tested. A combination of body weight and circumference measurements (like waist circumference) will give you a very good gauge of whether you’re losing body fat. If your circumference measurements are decreasing, you are likely losing fat.
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Re: Optimum fat levels

Postby casual_cyclist » Wed Oct 30, 2013 7:33 pm

mikesbytes wrote:Levels
- Seems to be always quoted as a % of total body weight. I've wondered if a better measurement would be kilo's of fat compared to your height and gender.
- Healthy range. A figure between minimum and max recommendation. If there any health difference within the range? Should we be smack in the middle
- Minimum level. Sport and Figure competitors will often want as little fat as possible, so to enhance their competition objectives. From a health viewpoint is this OK, or is it bad?
One answer:
There is a lot of controversy over what amount of body fat is optimal for overall health. A research paper by Gallagher et. al. in the American Journal of Clinical Nutrition (2000) came to the conclusion that certain low body fat ranges are “underfat”, which implies “unhealthy”. According to this research paper, men who are between 20-40 years old with under 8% body fat are considered “underfat”, whereas a “healthy” range is described as between 8-19%. For women in this same age group, any level under 21% is “underfat” and 21-33% is considered “healthy”.
http://www.builtlean.com/2010/08/03/ide ... age-chart/
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Re: Optimum fat levels

Postby sogood » Wed Oct 30, 2013 9:48 pm

mikesbytes wrote:However at what point do we stop the reduction of fat levels?
The human body has been managing the constitution of all our body functions for millions of years. Why don't you just leave that to what's natural and not micro-manage? The body only asks you to eat healthy, eat balanced, exercise and keep to a natural weight range. Then just let it decide how to dish it out the proportions. Some will have a bit more fat, some will have a bit less, some will look prettier, some will look more handsome...

The big question here is, are you dieting for health or dieting for sporting performance. They have considerably different end points.
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Re: Optimum fat levels

Postby mikesbytes » Thu Oct 31, 2013 9:07 am

sogood wrote:The big question here is, are you dieting for health or dieting for sporting performance. They have considerably different end points.
Guess you could also add body image to that list.

My fat levels are low enough to not have health issues related with excess body fat. So its really about sporting performance.

One advantage of low fat levels is if you want to increase muscle. Its far easier to increase muscle by putting on weight, combining weight gain with the appropriate training. Then you strip off the excess fat quickly, so to minimise muscle loss
If the R-1 rule is broken, what happens to N+1?

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Re: Optimum fat levels

Postby sogood » Thu Oct 31, 2013 9:14 am

mikesbytes wrote:Guess you could also add body image to that list.

My fat levels are low enough to not have health issues related with excess body fat. So its really about sporting performance.

One advantage of low fat levels is if you want to increase muscle. Its far easier to increase muscle by putting on weight, combining weight gain with the appropriate training. Then you strip off the excess fat quickly, so to minimise muscle loss
Then I guess the answer will be, when you get sick of the intense diet/exercise protocol to maintain your arbitrarily low body fat. If you can keep it up, then powers to you as long as you are reasonably sensible with it. There obviously is a level where it can start to adversely impact on one's health, but in a normal situation like your, you are hardly likely to get there. Think bulimic sufferers.
Bianchi, Ridley, Tern, Montague and All things Apple :)
RK wrote:And that is Wikipedia - I can write my own definition.

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