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It is common to see marketing for exercise routines that claim to target fat deposits in a particular part of the body. Examples:

But is there any science behind this?

I understand that certain exercises will target certain muscle groups, and can therefore specifically tone your thighs, stomach, legs, biceps, etc, which may make the selected body area look more attractive by some criteria.

But do specific exercises actually burn fat from particular parts of the body more than from others?

Flimzy
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There is no science to back up targeted fat loss, in fact there are studies to refute it.

http://www.yalescientific.org/2011/04/targeted-fat-loss-myth-or-reality/

Two major factors: First,

fat contained in fat cells exists as triglycerides. Muscle cells, however, cannot directly use triglycerides as fuel. It must be broken down to glycerol and free fatty acids, which then enter the bloodstream. As a result, the fat broken down to be used as fuel during prolonged exercise can come from anywhere in your body, not just the part that is being worked the most.

Second,

many of the exercises commonly associated with spot reduction do not actually burn many calories.

However, there is some science that supports a very tiny amount of spot-shaping to be possible, but it's very miniscule.

http://www.bodyrecomposition.com/research-review/are-blood-flow-and-lipolysis-in-subcutaneous-adipose-tissue-influenced-by-contractions-in-adjacent-muscle-in-humans-research-review.html/

One conclusion:

working a given muscle for 30 minutes at low to moderate intensities did increase fat cell lipolysis in blood flow.

However:

Based on the measured changes in blood flow and lipolysis, the researchers estimate that, in 30 minutes of local exercise, an additional .6-2.1 milligrams (one milligram is one thousandth of a gram) per 100 grams of adipose tissue adjacent to contracting muscle was mobilized.

First let’s assume that you’re carrying a whopping 5 kg (11.1 pounds) of fat in a specific area.

If local exercise can mobilize 0.6-2.1 milligrams of fat per 100 grams of fat mass, that works out to:

0.6-2.1 mg/100 grams * 1000 grams/kg * 5 kg = 30-105 milligrams of fat.
Or 0.03-0.1 gram of extra fat mobilized in 30 minutes of activity.

Now, a single pound of fat (0.454 kg) contains about 400 grams of fat so our hypothetical 11.1 pounds of fat contains 4,440 grams of fat. And 30 minutes of local activity mobilized at most 0.1 gram of fat. Whoo hoo. You’ll be ripped in about 1000 years.

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jgritty
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    Consider talking some about how targeted exercise does effect muscle tone and shape which is often confused with targeted fat loss. – DampeS8N Nov 04 '14 at 18:12
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    Alone the creative conversion from metric to imperial and back to metric units causing 5,000 grams of fat to contain 4,440 grams of fat should perhaps be enough to doubt the conclusions on the web page you're quoting. I can't find the full text of the publication the web site is using as a fact base, but I also assume that the web page author is mixing the numbers for blood flow in ml per 100g tissue per Minute and fat mobilization in mg per 100g tissue per exercise (30 Minutes). – Tor-Einar Jarnbjo Nov 04 '14 at 19:13
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    The math in the last paragraph is sloppy. 0.454kg ≠ 400 grams. 11.1 lb = 5034.9 g (not 4440 g). – Flimzy Nov 04 '14 at 19:35
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    instead of sloppy math, could the difference be to the fact that a pound of fatty tissue contains other things than fat cells or that fat cells aren't entirely lipids? (This would be a different sort of sloppyness.) – Dan Is Fiddling By Firelight Nov 04 '14 at 22:21
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    @DanNeely: It says "A single pound of fat contains about 400 grams of fat." There's not much room for other things in that conversion. I think it's just sloppy conversion. :) – Flimzy Nov 04 '14 at 23:00
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    @DanNeely: That could be an explanation, but that is not what is written and I find it important to point out that the entire last quote in this answer is a free interpretation of the findings in a science publication and not actually taken from the publication. The quote contains a few definitively incorrect statements and without actually understanding the science here, as I said, it looks as if the web page author is taking a few numbers from the publications just to give the numbers an entirely new meaning in his "conclusion". – Tor-Einar Jarnbjo Nov 05 '14 at 12:25
  • The math error is working against the conclusion. It's actually going to take 1150 years to get ripped. – jgritty Nov 05 '14 at 18:55
  • @jgritty: As I wrote, the conclusion is probably wrong anyway and not only because of the incorrect conversion. It's not a scientific study, but just to compare: During my last bicycle trip I lost 8kg while cycling 132 hours. Ignoring any changes in muscle mass, that makes a burn rate of about 60g fat tissue per hour and that was just moderate physical activity and not any special "fat burner exercises". – Tor-Einar Jarnbjo Nov 06 '14 at 12:04
  • Only a 750 hours to go until you lose a pound of fat! Or am I doing the math wrong? 60/132 = 0.5 grams per hour. 400g fat = 1pound, 400g/0.5 = 800 hours. How do you assure that the 8kg isn't just water weight anyway? – jgritty Nov 06 '14 at 17:33
  • @jgnitty: I am not sure what math you're attempting to do, it does not make much sense. It is impossible to "loose" 8kg of water without experiencing severe, if not even lethal, symptoms of dehydration. – Tor-Einar Jarnbjo Nov 06 '14 at 18:11
  • Where does it go then? Poop? – jgritty Nov 06 '14 at 20:47
  • Where does what go? – Tor-Einar Jarnbjo Nov 06 '14 at 22:32
  • The 8kg of you. – jgritty Nov 06 '14 at 22:33
  • The 8kg was likely used to power the physical activity. 60g of fat tissue contains somewhere around 450 to 500 kcal of energy and that could correspond very well to the energy required to ride a bicycle for an hour. – Tor-Einar Jarnbjo Nov 06 '14 at 22:41
  • @Tor-EinarJarnbjo You mean the physical mass of 8kg was directly converted to Thermal Energy (E=mc²)? Holy Cow - did we have a second sun in that time??? You should see that fat may contain energy, but it is not like the fat just disappears when you "burn calories" – Falco Feb 12 '15 at 16:26
  • @Falco: Where did I write that the physical mass of the fat was converted to thermal energy? I did not write that and that would of course be completely nonsense. – Tor-Einar Jarnbjo Feb 12 '15 at 19:24
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    @Tor-EinarJarnbjo I was referring to jgrittys argument. If you lost 8kg, the physical atoms with this mass had to go somewhere. So you lost Sweat/Breath, some CO2 and excrements. The question is, where did the 8kg come out of your body? You said "8kg were used to power the activity" this sounds like you drove by bike and the mass somehow was gone afterwards... – Falco Feb 12 '15 at 23:13