Lose weight: Physiology
The human organism is composed of various tissues, including a reserve called adipose tissue. This, mainly subcutaneous, has the function of storing energy reserves in the form of fat.
The management of these stocks takes place thanks to the communication of the adipose tissue with the rest of the organism, by means of the circulatory stream (transport of lipids, hormones and neurotransmitters).
Weight loss consists in the emptying, but not death, of the cells that structure the adipose tissue; therefore losing weight means reducing the amount of fat stored in the cells of adipose tissue.
Weight loss is a physiological process that affects the reduction of subcutaneous and / or visceral fat mass. It occurs when the organism tends to undergo a catabolic stimulus, ie "demolition". This stimulus can be more or less specific, depending on the hormones that regulate it, the sensitivity of the tissues, the state of nutrition, sex, age, etc .; generally, however, if not opposed by other specific mediators (typical of physical exercise, such as the somatotropic hormone), catabolism tends to affect the entire organism; it means that when you lose weight you tend to do it in an almost generalized way, while localized weight loss - that is concentrated in specific areas of the body - is very difficult to obtain (see below).
The catabolic hormones par excellence are: glucagon and adrenaline; on the contrary, the anabolic one par excellence is insulin. There is also a quantitatively less important anabolic mediator, which exerts a catabolic effect on adipose tissue but anabolic on proteosynthesis; it is the insulin-like growth factor (IGF-1) secreted thanks to the stimulus of the very famous somatotropin. Other important mediators are testosterone and thyroid hormones.
The tissues, some parts more than others, show a rather different chemical-regulatory sensitivity to catabolic and anabolic stimuli. For example, muscle tissue tends to degrade with extreme slowness compared to adipose tissue; this depends on the fact that the body tries to hinder muscle catabolism while promoting the disposal of fat (in compliance with specific biological functions).
Similarly, certain districts show a different sensitivity to fat accumulation. The adipose tissue located in the abdomen (android distribution, typical of men) is first affected by catabolism compared to that on hips and buttocks (gynoid distribution, typical of women). Moreover, whoever presents an apple conformation (the first one) loses weight more easily than one who manifests a pear conformation (the second one). There are many women and a few men with flat stomachs and prominent hips-buttocks, but also many men and a few women with a prominent belly and thin hips-buttocks. It is also important to keep in mind that the adipose tissue of subjects with an android deposit is prone to adipocyte hypertrophy (due to the secretion of the hormone cortisol, which is more frequent in humans); on the contrary, that of subjects with a gynoid deposit is more oriented towards hypertrophy and hyperplasia (increase in volume and number, due to the presence of estrogens, more frequent in women). These characteristics are greatly influenced by the state of nutrition in childhood.
The fact remains that, in order to lose weight, it is always necessary to establish the aforementioned catabolic condition. How? Increasing the overall energy expenditure compared to the caloric intake of the diet, trying above all to emphasize the cellular consumption of fatty acids compared to creatine phosphate, to carbohydrates and to branched amino acids.
Tummy Weight Loss: When is it Necessary?
Belly slimming is desired in various circumstances, basically divided into 3 points:
- In conjunction with an increased cardiovascular risk; in fact, the increase in abdominal circumference is associated with an increased risk of atherosclerotic formations. This condition is typical of obesity, therefore it correlates to metabolic disorders such as: type 2 diabetes mellitus, hypertension and lipid imbalances in the blood; this morphological feature is also among the diagnostic criteria of the metabolic syndrome. It is more serious when the accumulation of fat is visceral (inside the peritoneum and not outside the abdominal muscles), a feature that we will also mention in the next paragraph
- For other secondary reasons; for example, to encourage postural correction of any hyperlordosis that negatively affects one's lifestyle. In the male, being related to general obesity, belly fat is also responsible for many other joint discomforts, sleep impairment, fatty liver steatosis, gastroesophageal reflux with complications and other digestive tract disorders, sleep apnea, abnormal cardiac activity etc
- For aesthetic purposes.
Recall that body fat is not all concentrated in adipose tissue and a minor part of the total is defined as primary or essential. Equal to 3-5% in men and 8-12% in women, essential fat is crucial for the proper functioning of the man machine and for its survival. It is included in: cell membranes, bone marrow, nervous tissue (myelin sheaths), organs (kidneys, liver, heart, lungs etc.) and breasts (in women). Excessive weight loss, such as can be observed in people suffering from anorexia nervosa or in certain third world people, can affect these elements and cause a very serious pathological failure.
Women, before men, suffer the effect of excessive weight loss. Under a certain percentage of body fat (subjective parameter), fertile women experience an interruption of the menstrual cycle as a defense reaction of the organism (restoration usually takes place with the repurchase of 10% more than the weight in which is interrupted).
We conclude this paragraph by recalling that the percentages of body fat (subcutaneous, that measured with BIA and plicometry) considered normal are: 12-15% for men and 25-28% for women.
La Pancia: A Difficult Zone
The belly or abdomen is an area of great interest for all lovers of aesthetic culture. The average person (male and female) would like to have it flat, sculpted and with a thin waistline. On the other hand, the weight trend related to the general population in the West tends to grow, often beyond the normal-weight threshold. Ultimately, even if it is a district more subject to weight loss than others, to achieve the desired result it would be desirable that:
- There is no hyperlordosis condition; otherwise, even in conditions of maximum weight loss, the abdomen will always be prominent (factor independent of adipose tissue)
- An intra-visceral accumulation, typical of a sedentary lifestyle, of alcohol abuse and junk food (part of the android conformation) does not persist; however, in general, by correcting diet and motor activity, this type of fat is the quickest to leave
- There is a general predisposition to weight loss or a specific protocol is developed and the district is sensitive to catabolism
- There is a balance in the exchange of fluids between the circle and the interstices; translated, that there is no subcutaneous water stagnation (typical of sedentary people and anyone with precarious blood circulation)
- There is a predisposition of the track to be narrow and not wide; in this case, in the training protocol it would be better to avoid the exercises that overly hypertrophy the external and internal oblique muscles, and the transverses (factor independent of adipose tissue)
- The body does not slow down weight loss too much by reducing the fat mass.
Regarding the last point, there is also an inverse correlation between the size of the weight loss and the ease with which it occurs. Very fat subjects lose weight very quickly compared to normal weight subjects; it must therefore be borne in mind that, most of the time, the flat, narrow and sculpted belly corresponds to a percentage of fat below the average or even to the normality threshold. Therefore, it is logical to deduce that the desired aesthetic result will be all the more arduous to obtain, the more it is significant; nevertheless, the closer you get to the goal, the greater the difficulty becomes and the less the progression of the results.
How to Lose Your Belly?
We immediately begin the description of the methods specifying that weight loss is a general process and regulated only (or almost) by the body. It is therefore not possible to intervene as effectively as one would like on the localized weight loss of the belly, even if some professionals claim the opposite.
Those who claim to have understood the mechanism, suggest a very specific (not univocally accepted) protocol that we will illustrate in the next paragraph.
For now, let's try to understand how to reduce the percentage of excess fat in our body in a generalized way.
- Balance the diet. The diet must be low-calorie, balanced and well divided. These three criteria translate as follows:
- First of all, the missing energy compared to the maintenance of weight (normocalorica), must not exceed 30% of the total daily requirement in normal subjects and 10% in sportsmen who practice intense activity (personal opinion). Therefore, if the caloric needs of an individual are 2000Kcal / day, the slimming diet should provide no less than 1400Kcal or - if it is a person who practices intense activity - not less than 1800KCal.
- The nutritional balance provides for a breakdown of energy macronutrients equal to: about 45-65% of carbohydrates, 25-30% of lipids and the rest of the energy remaining in proteins; the percentages may vary slightly. Furthermore, the diet must guarantee the supply of mineral salts and vitamins, as well as fiber and other nutritional components (phytosterols, lecithins, polyphenols, etc.)
- Regarding the caloric subdivision in the various daily meals, this varies a lot depending on the specific case and on any training sessions. It is necessary that it foresees at least 3 main meals, that is a breakfast, a lunch and a dinner, approximately in proportions of 15%, 30-40% and 25-35%; it is also essential to provide 2-3 secondary meals or snacks, approximately 5-10%.
NB . Some adopt alternative dietary systems to that of the Mediterranean diet, such as the various high-protein diets (some of which are ketogenic), the zone diet, the Paleolithic diet, the blood group diet, etc. I personally do not agree with them, as they do not always respect the criteria of nutritional balance.
- Plan a specific physical activity protocol for weight loss; now the complications begin. In fact, to favor the cellular use of fatty acids contained in adipocytes (organized in triglycerides), two methods can be used, sometimes simultaneously:
- The first, the more traditional one, is based on the direct oxidation of lipids within the muscle cells. This type of physical activity must have the following characteristics: long duration (not less than 25-35 ', up to 60-90') and intensity included in the so-called aerobic zone, tendentially lipolytic, which varies according to subjectivity but is always below the anaerobic threshold. In practice, the longer you train at moderate intensities, the greater the disposal of lipids (used to meet the energy demands of training)
- The second method is more "modern" and revolutionary, but not always shared; it is frequently associated with alternative nutritional regimens (often characterized by a lack of carbohydrates, rich in proteins and sometimes poor in fats) and is based on the concept of increasing oxygen consumption at rest. This parameter, which normally depends on the basal functions, after a certain type of physical activity increases proportionally to the intensity and the time of exercise. Here the slimming protocol uses an indirect system, based on very high intensity sessions, almost totally anaerobic and often interspersed, therefore of shorter duration (High Intensity Training - HIT or High Intensity Interval Training - HIIT)
NB . It is possible to unify the two systems by exploiting an oscillatory intensity pattern, which moves from the lipolytic band to lactate but never maximal operating peaks, since it is necessary to guarantee the continuity of the training (recovery must be active).
Localized weight loss: Is it possible?
As anticipated, someone claims that localized weight loss, including that of the stomach, is not impossible to obtain.
Taking a very short step back, in point 4 of the paragraph entitled "La Pancia: A Difficult Zone", we talk about the correct exchange of fluids. This concerns the displacements from the circle to the interstices and vice versa, and mainly depends on the concentrations and the degree of vascularization.
With regard to concentrations, blood is more or less constant (oncotic and osmotic regulation); if this were not the case, some very serious health imbalances would appear. On the contrary, there is the possibility that the interstitial fluids become enriched with ordinary or tendentially obsolete molecules (some call them "toxins"), which in turn exert an osmotic effect, aggravating water retention; a very indicative example of this principle is also part of the formation of cellulite.
Personally, I believe that this is NOT a condition as frequent or proportionally so important, especially in those who practice regular physical activity (who are less predisposed). At most, it is reasonable to think that the degree of vascularization of adipose tissue can be of primary importance in all its interactions with the organism.
NB . The most vascularized portion of subcutaneous body fat is probably that of brown fat, or the substrate dedicated to increasing body temperature; its presence in the organism is generally very low (except for the ethnic group Yupik - esquimesi).
Well, this is the principle ridden by supporters of localized weight loss: with increasing vascularization it should also increase the ability to capture chemical signals (hormones and neurotransmitters), but above all the release of fat to the bloodstream.
Now, the fundamental question is: how could vascularization be increased?
If the adipose tissue had the same properties as the striated muscle tissue, the objective would not be difficult to achieve, since the increase in vascularization (number and extent of the capillaries) is one of the responses to the aerobic training stimulus. However, for the fat (as well as for the integuments) this system cannot be applied.
To date, various physical methods have been proposed such as: localized massage (self-massage, vibrating bands, automatic massagers, etc.), heating (saunas, Turkish baths, synthetic elastic bands, etc.) and, finally, localized physical exercise. Precisely in relation to the latter, in the last 40 years the researchers have carried out many in-depth studies, some of them with conflicting results, but most of them are undoubtedly oriented to refute this theory.
On the other hand, it is not possible to ignore the opinion of those working in the field and certain high-level bodybuilders; excluding nutrition (supplements, notified and not) and chemistry (doping drugs) for a moment, various professionals report a noticeable improvement in results significantly increasing training volume and decreasing intensity. It could also be the direct oxidative increase caused by the greater energy commitment. If this were the case, the same result on the belly could be achieved by walking for an hour, rather than 1, 000 abdominals at a time.
To complicate matters, we put the conflicting opinion of other bodybuilders, who are also of the highest level, who even DO NOT train their tummy muscles and maintain a "national podium" abdomen.
Conclusions
To conclude, it is important to stress that the basis of the slimming process is the diet. While training, regardless of the improvement in health, if the diet does not meet the criteria of:
- Negative balance (less calories than consumed)
- Nutritional distribution
no significant change can occur in the thickness of the fat folds.
I want to clarify that even the extreme diet does not represent a correct behavior. Even with the support of certain dietary supplements, organizing the diet by breaking down carbohydrates (in the hope of increasing fat oxidation) can lead to an excessive increase in muscle catabolism; it is therefore sufficient to take not less than 45% of carbohydrates, with a low glycemic index and being careful not to overdo the portions (an excessive glycemic load could excessively increase the increase in insulin).
The same is true for the total lipids which, on the other hand, if too lacking in the diet could induce the insufficiency of essential fatty acids (omega 3 and omega 6), phospholipids and other secondary components, phytosterols and lecithins (undocumented in literature) and of liposoluble vitamins (A, D, E, K).
As regards the protocol of physical activity, the mixed one is certainly the most complete but requires a very accurate organization; therefore, it should be drafted by a professional. The safest alternative is always that of moderate and protracted aerobic activity, obviously respecting any pathologies or special conditions.
With regard to localized weight loss, self-massage or the performance of some specific exercise are not (normally) harmful to health; try not harm, but it is always better not to put too many expectations on it and focus more on diet and sport.
