Under the microscope, fat cells are massed together in packets of cells like a Kowloon high-rise. The cells specialized to store excess energy are colloquially called fat cells, but to the histologists and pathologists of the world, they’re called adipocytes. If examining the block of fat under a microscope, the fat cells collectively bunch together shoulder to shoulder and take the name adipose tissue. Even in fairly thin individuals with very low overall % body fat, pinching deeply around the lower belly reveals a fold or two of thick, loose tissue, the bulk of which is adipose tissue.
The focus of fat distribution has characterized individuals as either “Pear” or “Apple” with the descriptive pear assuming a more hips, thighs and legs distribution of fat, and apple as central fat distribution. The evolutionary justification for each is simple. Both in the final analysis are “centrally” distributed with apple fat being carried higher than pear fat. Both allow for free use of limbs and unobstructed senses.
Consider the physiological options with energy accumulation in obesity. If fat accumulated in the chest cavity, breathing would be impaired at very low adipose expansion. If fat were only accumulated on the arms, the arms would become useless and survivability of the organism would be rapidly diminished. Fat around the head and neck in any location to the same capacity of apple or pear distribution, would render the head enlarged with large cumbersome folds of fat around the eyes or engrossing the neck. The natural result of fat accumulation is to render preservation of an unencumbered organism with far too much stored adipose. Still, the organism can move, sense, survive and become limited by the accumulation of fat, but retains survivability skills.
From skin to adipose the layers are epidermis, dermis, hypodermis and adipose. And beneath the adipose tissue is the abdominal musculature—the “abs” or rectus abdominus. Going a level deeper, through the peritoneum and into the abdominal cavity, fat again proliferates on and in the omentum. The omentum is difficult to describe to the novice. Think of the omentum as a large gangly growth of adipose and loose connective tissue covering and surrounding the bowel. Central obesity is a massive collection of fat within the hypodermis (sometimes many centimeters thick) and a large collection of internal fat within the omentum. In some circles, omental fat is really what describes central obesity and the risk factors for the metabolic syndrome.
The tenants of this project I call adipose tissue are not even loosely thought of as an organ like the cells making up the liver or the spleen; but make no mistake, they collectively form a specialized kind of cell that lives for the sole purpose of storing excess energy in the form of triglyceride or fat.
Again, concentrating in certain locations, like around the mouth, nose or eyes, adipose tissue could obviously become a problem. Therefore the tissue is diffusely located in specific distributed locations such that the accumulation of storage fat would not impede day-to-day activities. As more and more excess energy is accumulated, the back of the arms, riding over the triceps muscles and in many cases encircling the entire upper arms, collects large deposits of adipose tissue. The thighs widen, or the abdomen becomes pendulous as more triglyceride accumulates in adipocytes.
Again, by design, the fat encircling the upper arm is less intrusive upon daily tasks than say a collection of fat surrounding the lower arms or fingers. An inspired quote by Eliel Saarinen, a Finnish-American architect and city planner, has applications to biological systems as well as the distribution of fat tissue around the human body:
“Always design a thing by considering it in its next larger context—a chair in a room, a room in a house, a house in an environment, an environment in a city plan.”
At that Eliel Saarinen described the evolution of human development. As an aside, the popular term, “cellulite” coined in the early 1970’s by non-medical beauty solon types, was thought to be a collection of “fat gone bad” by incorporating fat with water and a collection of “toxic wastes” leading to dimpling of the skin over the fat. The dimpling is actually a result of the connective tissue networks making up globular collections of adipocytes near the surface of the skin. The connective tissue holds the adipocytes firmly in groups and pulls on the surface as it expands. The term cellulite lead to a raft of possible snake oil cures including plastic pants, massage techniques, oil treatments and rollers and skin brushes to allow the cellulite to disappear. An excellent history and chronicle of the alleged treatments of cellulite are outlined nicely by Stephen Barrett M.D. on a wonderful website called Quackwatch.[i]
All adipocytes are cells with the primary purpose of holding a central core of energy dense fat or triglyceride within the cells matrix. The image above shows a cell with a large droplet of fat or triglyceride inside the cell. The nature and origin of triglyceride will be discussed shortly as the term “fat” is further dissected and defined. Again, those particular sites of collection described above have evolved as a distribution pattern allowing excess energy to be stored but not collecting in such a way to disrupt daily activities. Running with a moderate collection of adipose around the upper legs or thighs may slow the pace slightly, but it shouldn’t offer a significant obstruction to the mechanical motion of the legs. Moving up the body, lifting a heavy object with adipose around the upper arms or with adipose in the central portion of the abdomen ringing the belly like a donut, will not keep the object from being lifted or manipulated.
Finally and contrary to popular belief, the collections of adipose tissue are not for the most part responsive to the muscle groups they surround. That means doing more sit-ups will not decrease belly fat if the energy balance falls in excess of the energy needs. And upper arm fat will not respond specifically to biceps and triceps exercises. Instead, the muscles of the abdomen and upper arm will most likely become strengthened and may actually enlarge or hypertrophy beneath the pad of adipose. However, adipose tissue reacts to global energy needs not spot exercising.
The individual tenants of this complex referred to above live for one reason only: the storage of excess energy. The single adipose cell is rather large and dominated by a considerable amount of fat or triglyceride in the cell cytoplasm, appearing somewhat like a tanker truck. The truck and the driver (the nucleus of the cell, in purple) are dwarfed by the huge tank full of yellow fat. In the case of the adipocyte, a thin layering of cell cytoplasm surrounds the huge fat droplet, which as the figure shows, pushes the other cell components out to a thin layer around the fat droplet. The typical ingress and egress of triglyceride from the adipocyte, as above, occurs as a result of global energy needs. Hormone sensitive lipase is the key to moving fat in and out.
[i] Barrett S. “Cellulite” Removers. Quackwatch. http://www.quackwatch.org/
The focus of fat distribution has characterized individuals as either “Pear” or “Apple” with the descriptive pear assuming a more hips, thighs and legs distribution of fat, and apple as central fat distribution. The evolutionary justification for each is simple. Both in the final analysis are “centrally” distributed with apple fat being carried higher than pear fat. Both allow for free use of limbs and unobstructed senses.
Consider the physiological options with energy accumulation in obesity. If fat accumulated in the chest cavity, breathing would be impaired at very low adipose expansion. If fat were only accumulated on the arms, the arms would become useless and survivability of the organism would be rapidly diminished. Fat around the head and neck in any location to the same capacity of apple or pear distribution, would render the head enlarged with large cumbersome folds of fat around the eyes or engrossing the neck. The natural result of fat accumulation is to render preservation of an unencumbered organism with far too much stored adipose. Still, the organism can move, sense, survive and become limited by the accumulation of fat, but retains survivability skills.
From skin to adipose the layers are epidermis, dermis, hypodermis and adipose. And beneath the adipose tissue is the abdominal musculature—the “abs” or rectus abdominus. Going a level deeper, through the peritoneum and into the abdominal cavity, fat again proliferates on and in the omentum. The omentum is difficult to describe to the novice. Think of the omentum as a large gangly growth of adipose and loose connective tissue covering and surrounding the bowel. Central obesity is a massive collection of fat within the hypodermis (sometimes many centimeters thick) and a large collection of internal fat within the omentum. In some circles, omental fat is really what describes central obesity and the risk factors for the metabolic syndrome.
The tenants of this project I call adipose tissue are not even loosely thought of as an organ like the cells making up the liver or the spleen; but make no mistake, they collectively form a specialized kind of cell that lives for the sole purpose of storing excess energy in the form of triglyceride or fat.
Again, concentrating in certain locations, like around the mouth, nose or eyes, adipose tissue could obviously become a problem. Therefore the tissue is diffusely located in specific distributed locations such that the accumulation of storage fat would not impede day-to-day activities. As more and more excess energy is accumulated, the back of the arms, riding over the triceps muscles and in many cases encircling the entire upper arms, collects large deposits of adipose tissue. The thighs widen, or the abdomen becomes pendulous as more triglyceride accumulates in adipocytes.
Again, by design, the fat encircling the upper arm is less intrusive upon daily tasks than say a collection of fat surrounding the lower arms or fingers. An inspired quote by Eliel Saarinen, a Finnish-American architect and city planner, has applications to biological systems as well as the distribution of fat tissue around the human body:
“Always design a thing by considering it in its next larger context—a chair in a room, a room in a house, a house in an environment, an environment in a city plan.”
At that Eliel Saarinen described the evolution of human development. As an aside, the popular term, “cellulite” coined in the early 1970’s by non-medical beauty solon types, was thought to be a collection of “fat gone bad” by incorporating fat with water and a collection of “toxic wastes” leading to dimpling of the skin over the fat. The dimpling is actually a result of the connective tissue networks making up globular collections of adipocytes near the surface of the skin. The connective tissue holds the adipocytes firmly in groups and pulls on the surface as it expands. The term cellulite lead to a raft of possible snake oil cures including plastic pants, massage techniques, oil treatments and rollers and skin brushes to allow the cellulite to disappear. An excellent history and chronicle of the alleged treatments of cellulite are outlined nicely by Stephen Barrett M.D. on a wonderful website called Quackwatch.[i]
All adipocytes are cells with the primary purpose of holding a central core of energy dense fat or triglyceride within the cells matrix. The image above shows a cell with a large droplet of fat or triglyceride inside the cell. The nature and origin of triglyceride will be discussed shortly as the term “fat” is further dissected and defined. Again, those particular sites of collection described above have evolved as a distribution pattern allowing excess energy to be stored but not collecting in such a way to disrupt daily activities. Running with a moderate collection of adipose around the upper legs or thighs may slow the pace slightly, but it shouldn’t offer a significant obstruction to the mechanical motion of the legs. Moving up the body, lifting a heavy object with adipose around the upper arms or with adipose in the central portion of the abdomen ringing the belly like a donut, will not keep the object from being lifted or manipulated.
Finally and contrary to popular belief, the collections of adipose tissue are not for the most part responsive to the muscle groups they surround. That means doing more sit-ups will not decrease belly fat if the energy balance falls in excess of the energy needs. And upper arm fat will not respond specifically to biceps and triceps exercises. Instead, the muscles of the abdomen and upper arm will most likely become strengthened and may actually enlarge or hypertrophy beneath the pad of adipose. However, adipose tissue reacts to global energy needs not spot exercising.
The individual tenants of this complex referred to above live for one reason only: the storage of excess energy. The single adipose cell is rather large and dominated by a considerable amount of fat or triglyceride in the cell cytoplasm, appearing somewhat like a tanker truck. The truck and the driver (the nucleus of the cell, in purple) are dwarfed by the huge tank full of yellow fat. In the case of the adipocyte, a thin layering of cell cytoplasm surrounds the huge fat droplet, which as the figure shows, pushes the other cell components out to a thin layer around the fat droplet. The typical ingress and egress of triglyceride from the adipocyte, as above, occurs as a result of global energy needs. Hormone sensitive lipase is the key to moving fat in and out.
[i] Barrett S. “Cellulite” Removers. Quackwatch. http://www.quackwatch.org/
4 comments:
WG, I can see how this article can send many attempting to lose weight/ fat screaming out of the gym. :-)
You say: "However, adipose tissue reacts to global energy needs not spot exercising."
My trainer says: "If you are not going to lose that fat all around the body, no point doing sit-ups if your six-pack will be hidden under layers of adipose.."
PS: While I postpone my blog makeover until after the thesis, I am adding your blog to my links. I hope that is ok. Thanks.
Shefaly: My intention wasn't to dissuade any gymgoer from doing their do diligence. By the way, what is your thesis?
Hi WG, I meant it as a joke of course. Seriously though, your post should encourage many a gym-goer to do more due diligence and also to re-adjust their expectations of the outcomes of research.
In my thesis, I am examining some policy formulation models using a case study of obesity, for which I first conducted a multidisciplinary literature review and then interviews with the participants who influence the policy making process directly/ overtly and indirectly/ covertly. It is a health policy and industry strategy focused research in the broad area of decision-making in management. I am also an engineer, so that influences my philosophical framing and research design process. Sorry, very long answer I think...
I am writing it up at present, so I have obesity on the brain, so to speak.
Oops, I meant 'outcomes of exercise programmes' not 'outcomes of research'. Thanks.
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