It’s hard to say where the excuse “I have a big bone” came from. But you can publish a text about how much the skeleton weighs and how much its weight can vary from person to person. different people.
Dry, fat-free and dehydrated human skeleton(that is, what will remain of you and me in this world) on average weighs only about 4 kg for men and about 2.8 kg for women. In percentage terms, the skeleton occupies approximately 6-7% of the body weight of an adult.
Bone density makes adjustments
We all know from the school curriculum what density is - and so, with the same volumes, the skeletons of different people can have slightly different weights, i.e. Some people will have denser bones, some less. How big a difference can there be and what does it depend on?
Bone mineral density can change with age (including due to osteoporosis), with concomitant diseases, nutrition (decreases with poor nutrition, and vice versa - with adequate nutrition). Bone density also depends on weight loss or weight gain: scientists have calculated that For every 1 kg of body fat lost, an average of about 16.5 g of bone minerals is lost, in fact, when gaining the same 1 kg of fat, approximately the same amount is restored (Jensen et al., 1994,), against the background of the existing training volume.
Here are the average normal values for bone density, including data for athletes and athletes who are developing adaptation of bone tissue to impact loads, and an approximate calculation of the difference in grams between these values, so that you can clearly understand what the overall value for the total bone/skeletal weight is, has bone mass density.
Data on bone density in adults (173 people, 18-31 years), different types sports: runners (R), cyclists (C), triathletes (TRI), judokas and wrestlers (HA), football and handball players and basketball and volleyball players (TS), student athletes, non-specialized in sports (STU), and non-training (UT) ).
Average values for bone mass density in adults are in the region of 1.0 – 1.2 g/cm2. Roughly speaking, this can be translated as +/-10% for different people depending on the factor.These values vary depending on age, gender, race, level and type physical activity, nutritional status, body condition, presence of diseases, etc. But on average, it’s something like this.
Data on skeletal weight and bone density of people of different age groups:
BMC – skeletal weight in grams, BMD – bone density in g/cm2. BF – black women, WF – white women. BM – black men, WM – white men.
Let's take the data from the last table as an example and take the cutoff values: the lowest bone density (in white women, the case of the lowest density is 1.01 g/cm2) and the highest bone density (in a dark-skinned man, the case of the highest density is 1.42 g/cm2). This gives us the difference between the person with the lowest (lightest bones among hundreds of subjects) and the person with the highest bone density (lightest heavy bones of all) is only about 0.7 kg with an average skeleton weight.
By the way, even growth hormone does not make significant adjustments to bone density. Scientists conducted a controlled 15-year study in which growth hormone injections were given to more than 100 people. Bottom line: over 15 years, the average increase in bone mass was only 14 grams.
Wide but light
Ultimately what we have is: what total mass human bones, excluding fat and liquid content, is something like 4-5 kg in adult men and 2-3 kg in adult women.
Within these same boundaries, the mass may fluctuate, depending on the bone mass density, but again this difference will not be so significant, in any case - up to 1 kg, depending on the bone mass density.
By and large, talk about “broad bones”, “powerful frames”, which radically affect the overall weight of a person’s body, “fat power” and genetic predisposition to increased weight gain, in fact, are not entirely comparable with real situation things.
Yes, the difference in height and build certainly gives its own shifts in various indicators of bone mass from person to person, but these indicators do not differ by 5-10 kilograms, but amount to on average no more than 2-3 kg from person to person.
1. Jensen, L.B., F. Quaade, and O.H. Sorensen 1994. Bone loss accompanying voluntary weight loss in obese humans. J. Bone Miner. Res. 9:459–463.
2. “Dear Lyle...”: bone density and training” by Znatok Ne.
3. Trotter M, Hixon BB. Sequential changes in weight, density, and percentage ash weight of human skeletons from an early fetal period through old age. Anat Rec. 1974 May;179(1):1-18.
4. Schuna JM Jr et al. Scaling of adult regional body mass and body composition as a whole to height: Relevance to body shape and body mass index. Am J Hum Biol. 2015 May-Jun;27(3):372-9. doi: 10.1002/ajhb.22653. Epub 2014 Nov 8.
5. Wagner DR, Heyward VH. Measures of body composition in blacks and whites: a comparative review. Am J Clin Nutr. 2000 Jun;71(6):1392-402.
6. Nilsson M, Ohlsson C, Mellström D, Lorentzon M. Sport-specific association between exercise loading and the density, geometry, and microstructure of weight-bearing bone in young adult men. Osteoporos Int. 2013 May;24(5):1613-22. doi:10.1007/s00198-012-2142-3. Epub 2012 Sep 26.
7. Petra Platen et al. Bone Mineral Density in Top Level Male Athletes of Different Sports. European Journal of Sport Science, vol. 1, issue 5, ©2001 by Human Kinetics Publishers and the European College of Sport Science
8. Rothney MP et al. Body composition measured by dual-energy X-ray absorptiometry half-body scans in obese adults. Obesity (Silver Spring). 2009 Jun;17(6):1281-6. doi: 10.1038/oby.2009.14. Epub 2009 Feb 19.
9. Tomlinson DJ et al. Obesity decreases both whole muscle and fascicle strength in young females but only exacerbates the aging-related whole muscle level asthenia. Physiol Rep. 2014 Jun 24;2(6). pii: e12030. doi: 10.14814/phy2.12030.
10. Human Body Composition, b.918, Steven Heymsfield, Human Kinetics, 2005, p-291.
11. Elbornsson M1, Götherström G, Bosæus I, Bengtsson BÅ, Johannsson G, Svensson J. Fifteen years of GH replacement increases bone mineral density in hypopituitary patients with adult-onset GH deficiency. Eur J Endocrinol. 2012 May;166(5):787-95. doi:10.1530/EJE-11-1072. Epub 2012 Feb 8.
12. Locatelli V, Bianchi VE. Effect of GH/IGF-1 on Bone Metabolism and Osteoporsosis. Int J Endocrinol. 2014;2014:235060. doi: 10.1155/2014/235060. Epub 2014 Jul 23
Asthenic body type . Women of this constitution are characterized by general thinness, long and thin neck, narrow shoulders, flat and narrow rib cage, elongated thin limbs, elongated face and thin nose. Height is often above average. The muscles of such women are poorly developed. Therefore, they lack strength and endurance. But the representatives of this group are energetic, light and graceful, and have little weight. One of the obvious advantages of an asthenic physique is the minimal tendency to be overweight. When choosing sports disciplines, it is better to give preference to those that are aimed at developing missing skills: strength and endurance. These include swimming, aerobics, and dancing. To correctly classify your body type as thin-boned, measure the circumference of your wrist. In the group under consideration, it should be less than 16 cm.
Normosthenic body type . In women of this constitution, the main body dimensions are proportional. Such ladies often have slender legs, thin waist and, in general, a harmonious figure. Height is usually average. Such people are naturally well-coordinated, sharp and fast. Among sports disciplines, they are best suited game types(volleyball, basketball, etc.), as well as tennis, water aerobics. The wrist circumference should be between 16 and 18.5 cm.
Hypersthenic body type . Women of this constitution have heavy and wide bones, voluminous shoulders, a wide and short chest, and slightly shortened limbs (as a rule). Height is often below average. By nature, such ladies have strength and endurance, but are deprived of flexibility and grace. Therefore, recommended sports disciplines the following: yoga, callanetics, martial arts etc. In addition, the disadvantages of a hypersthenic body type include a low metabolic rate, which implies an increased tendency to be overweight. The circumference of the wrist for a large-boned physique is more than 18.5 cm.
Normal height and leg length
You can also determine your body type based on your height and leg length. For a normal and broad-boned body type, normal height is considered to be between 166 and 170 cm, while for an asthenic type it is within 168 - 172 cm. There are certain proportions between the height and length of a person’s legs. Legs are considered short if their length is less than half the height.
The length of the legs is measured from the tubercle of the femur located opposite hip joint, to the floor.
The ideal leg length should be within the following limits:
- asthenic type: legs are 2-4 cm longer than half the height
- normosthenic type: legs are 4-6 cm longer than half the height
- hypersthenic type: legs are 6-9 cm longer than half the height
Don't be discouraged if your performance doesn't match the ideal. Create visibility required length feet can be done using heels. By the way, this is one of the ways to choose the ideal heel height. Just count how many cm you fall short of the standards and wear heels of exactly that height.
Whiteles and the Pinier index
Whiteles(from the English vitels vital organs) - dimensions female figure- height, leg length, chest, waist, hips
Normal “whites” indicators for young women:
Body typeAsthenicNormosthenicHypersthenicChest circumference84 - 86 cm1/2 height + 2-5 cm1/2 height + 8-10 cmBust volumeChest circumference + 4-6 cmChest circumference + 8-10 cmWaist circumference60 - 64 cmHeight - 105 cm70 - 76 cmHip circumferenceWaist circumference + 30 cmWaist circumference + 30 cmWaist circumference + 28 cmFor a more objective assessment, you can also use the Pinier index indicators.
Pinier index = standing height (cm) – (body weight (kg) + chest circumference (cm))
With indicators less than 10 – strong (dense) physique; 10-25 – normal; 26-35 – weak; more than 35 – very weak.
Weight norm
Of course, excess weight does not decorate any woman. Beauty is health, slimness, fitness. It is these external data that men consider ideal on a subconscious level. In addition, obesity leads to premature aging of the entire body. That is why it is very important to know the boundaries of your normal weight. But what do they depend on? Is it just a matter of height and age? Not only that. To correctly determine your weight norm, you need to take into account the characteristics of your body: general body structure (type of constitution), shoulder width, chest features, etc.
However, we must not forget that excess weight is not always a sign of excess fat in the body. Adipose tissue is an integral part of any living organism. And he needs it vitally. Under normal conditions, the amount of fat in men is 1/20, and in women 1/16 of body weight. And about 75% of all fat is located directly under the skin. A small amount of fat under the skin protects against bruises and hypothermia. A certain minimum of fat in internal organs keeps them in the right place, protects them from excessive mobility, injuries and shocks. In addition, fat is energy that can be used when needed.
Our website presents several methods for calculating weight norms based on the characteristics of your body type.
Using the formula below you can find out your weight per 1 centimeter of height:
Weight per 1 cm of height = body weight (grams) / height (centimeters)
Knowing your body type, multiply the coefficient by your height and you will get your normal weight.
The maximum permissible weight for women at a certain age can be calculated from the table below:
Well, ladies, let's take out a centimeter and measure your wrist from bone to bone... I'm exactly 18, how much is yours?
Until the age of 25, I was firmly convinced that I would never have to limit myself in food. Now I understand that if I had been a little less lucky with my metabolism, then with such eating habits I simply would not have gotten through the door. And a few years ago, I was sincerely perplexed as to why someone couldn’t eat half a cake at night or denied themselves fresh baked goods. I remember the anxious looks of the photo editor at one of my previous jobs, when I devoured pies one after another, sitting at the monitor. “Eh, you’ll ruin your figure!” - he sighed, and I just laughed.
But, despite the fact that I was thin since childhood, beautiful abs I could never brag. “You have such a structure: your stomach is set close,” my family told me, and I took it for granted. Well, what can you do - such heredity! I think that I would have spent my whole life with this naive confidence if one day I had not come to the gym. I came, as usually happens, with the intention of “toning up my muscles a little.” Months of “amateur” and useless exercises - and then the truth suddenly revealed: you can radically change your body if you just want to. True, this requires not only training, but also thoughtful nutrition. And “close-set stomach” is just as stupid as “wide bone.” We eliminate buns and cakes - we get the coveted stripe on the stomach.
Plenty of other examples from life lead me to believe that what we consider an irresistible genetic trait is very often nothing more than the result of our ignorance, laziness and inaction.
Almost all participants in the “Lose Weight with Lady” project suffering from excess weight, grew up in families where obesity was considered hereditary. Although in the process of communicating with nutritionists, it turned out that the reason for everything was the wrong lifestyle to which all family members were accustomed. Yes, most often the culprit is the recipes for rich borscht and pork chops, passed down from generation to generation, and joint evenings watching TV, and not the “big bone”.
X-ray of a person weighing more than 200 kg. As you can see, the width of the bone is quite standard
I look with admiration at one of my colleagues: athletic, slender, energetic Ksyusha. Five days a week she can be seen in the mornings in the corporate gym, and at exactly 13.00 she has lunch in the kitchen: salad, vegetables, fish. She counts calories and doesn’t look exhausted at all: on the contrary, she’s full of energy. A few years ago, Ksyusha was able to lose 20 kg and now maintains herself in great shape. “When I now come to visit my relatives, they say that they are ashamed of me. That when they look at me, they understand that this is not a “big bone,” but banal laziness.”
Another example: I once met a girl who teaches strip plastic. I was amazed by her flexibility and grace, and how easily she did the splits. I was amazed when I found out that by nature her body was literally “wooden”, and stretching was always incredibly difficult for her. But Katya wanted to dance so much that she constantly overcame herself. Over the years she had to learn what others found easy. Can you imagine how disappointing it is: a beginner, as soon as he comes to class, easily does something that you only succeeded in a couple of years later? But that didn’t stop her: “I compared myself not with others, but with who I was in the past, and I realized that I was moving forward.”
So does the notorious heredity exist, and how important is it in improving the body?
Yes, indeed, the metabolic rate of different people can vary, although this factor is not always due to heredity. And there are lucky people who are able to eat almost as much as they want and not gain weight, but most often this is only until a certain time. So, disordered eating had practically no effect on my figure until I was 25. But at some point I still realized that I was starting to look different from what I would like. After all, in addition to the quantity of the body, there is also quality - it can be elastic or loose, fit or flabby, young or old. Sports and healthy eating Everyone needs them, regardless of weight and size. But for those who are naturally lucky, it is often difficult to take charge of themselves. And when the reflection in the mirror begins to upset you, it is often too late to change something radically. So luck is questionable!
There are those who know for sure: they only need to eat a couple of pieces of cake in the evening to see +1.5 kilograms on the scales in the morning! These women, as a rule, realize earlier that beautiful body means hard work. And when, after 30 years, their girlfriends, lucky skinny women who have never denied themselves anything all their lives, turn into “skinny fat”, they, who always kept themselves in control, will remain slim and young. If you are one of those who are naturally unlucky, remember: “bad” heredity in this case can turn into your trump card!
In a word, have no doubt: in matters of harmony, genetics is far from the determining thing. The only things that really matter are lifestyle, nutrition and how strong your desire to change. And if, after reading this column, you still want to be indignant: “It’s easy for you to say, but I really have a wide bone,” just open the refrigerator now. Look closely at sausages and frankfurters, drinking yogurt, which contains more sugar than milk. Count how many times a day you drink tea with “something tasty.” And then repeat this phrase again.
Many people who suffer from excess weight today grew up in families where obesity was considered hereditary. Although in the process of communicating with nutritionists, it turned out that the reason for everything was the wrong lifestyle to which all family members were accustomed.
Yes, rich borscht with spoons standing in it, fatty cutlets, as well as joint evenings watching TV while watching “something tasty” are most often to blame.
Often what we think is an irresistible genetic trait turns out to be just the result of overeating. Is this bad? Of course not, that means we can fix everything!
Myth or reality: does it happen?
The photo shows two twin sisters. Those. parents, heredity and predisposition they have in common! They really like to confuse genetics and incorrect eating habits instilled in the family! “Everyone in my family is fat” is correct: everyone eats dumplings with mayonnaise together at night.
IMPORTANT POINT: Yes, differences in skeletal structures really exist, it’s stupid to deny it. There are girls with wide hips, even with a low percentage of body fat, and there are girls with a boyish figure and an almost complete absence of curves.
People with narrower bones tend to have smaller hands and feet, thin fingers, if a woman, then narrow shoulders, narrow chest. Those who have wider bones in their structure, respectively, have wider feet and wrists, and, most importantly for the purposes of this article, more muscle mass .
The wider the bone, the more muscle, which are attached to it. But if you believe that muscles are much heavier than fat, then we advise you to watch this video. It perfectly shows that the weight of animal fat and muscle is approximately the same!
There is also other data on this topic. Muscle tissue weighs more than fat, but not by several times, due to different densities:
muscle density – 1.3 g. on cm;
fat density is about 0.9 g. on cm
This means that fat weighs about one and a half times less than muscle. There is a difference, but not as significant as many people think.
Therefore, with all the parameters taken into account, complaints about that very “wide bone”, which adds from 5 to 15 kg. to a person’s overall body weight, to “fat power” and genetic predisposition to increased weight gain, in fact, are not entirely comparable with the real state of affairs.
And the amount of fat has absolutely nothing to do with broad bone . Let your hips be a little wider than others, but these will be two big differences: whether they will be with 10 kg of fat on them or with 2. Yes, a wide bone can give external massiveness (although you must agree, this is more than attractive), but not an additional 50 kg of fat.
Photo
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How to determine?
How to understand whether a bone is wide or not? Feel yourself 🙂 If you feel fat through the skin, then, alas, it won’t be possible to blame it on the bones. But if under the skin you feel a hard surface with a slight layer of fat, then you are the happy owner of chic, wide hips which an overwhelming number of men consider sexy!
What does it mean?
Looking for a wide bone means one thing: you obviously need to lose weight! Many people believe in the big bone more than the big bang theory. With the exception of the inner part where the brain is located, bones are solid structures made of calcium.
Once you have stopped growing, the size of your bones cannot be changed without causing serious harm to your health. However, you can change the size of your body fat. This is what will help you change your appearance. Therefore, read to the end of this article and find out how to solve the problem.
So what if you don’t see a waist like young Gurchenko’s? But they didn’t come close to Krachkovskaya. So love yourself and take care of yourself without any complexes!
How to lose weight?
What is body positivity in simple words?
Unfortunately, the true meaning of body positivity is now lost behind the showdowns between overweight ladies and clothing companies (as well as, by the way). The message is that a person (yes, not only women, but also men) does not have to be “attractive” to anyone according to some glossy standards.
If a person is satisfied with his own beauty, he is not obliged to chase utopian newfangled trends. We are absolutely not against fat people and support such body positivity: you don’t need to be like someone else, you need to be better than yourself yesterday. Let a person decide for himself what kind of life to live.
Love yourself for who you are. But do not harm other people by doing this, do not force them to love you - your freedom ends where the freedom of another person begins!
Body positivity is about the diversity of beauty. About the ability to see it everywhere - in others, in yourself. Around. About your right to have a nose, not like the models in the magazine, and a couple of extra kilos. About the ability to enjoy the capabilities of your body - from running jumps into the water to sex.
Love yourself, but don't indulge yourself! Today they talk a lot about love, especially that you need to love yourself first. But no one talks about what kind of love this should be. No one says that love can be painful: overly protective, destructive, pulling back, interfering with progress.
No one says that love is not the satisfaction of all one’s desires, it is not self-pity, it is not “wrapping oneself in cotton wool” and deliberately avoiding difficulties. True love is not about giving in to your destructive habits, but about becoming a better person, moving forward: taking care of your health and well-being.
Loving yourself should make you a better person. If this is not the case, then it is a surrogate. Chocolate, cigarette, Bloody Mary - these are not manifestations of your self-love, but only an ersatz palmed off by your subconscious.
For example, you decide to go on a diet, but at the same time you perceive it as a cruel restriction, as a mockery. You suffer by giving up high-calorie, fatty, sweet foods. And in the depths of your subconscious the conclusion is born that you do not love yourself, since you voluntarily condemn yourself to such sacrifices.
Your subconscious mind reasons within the framework that you yourself have given it. Everything in your life is mixed up - it seems to you that self-love, true pleasure lies in following your emotions and the thoughts that you associate with them, and the slightest deviation from the given trajectory means stress and pain.
Remember, everything is in your head and everything is in your hands. Our article can help you deal with such problems.
Funny video
Don’t be upset about your weight, but rather listen to the funny song “Oh, you’re a wide bone”:
It is believed that thin bones- this is a trait human body, which interferes with muscle gain. IN gyms you can hear: a thin bone will not grow much meat.
Thin bone and body type
The thickness of the bone is important parameter determining a person’s somatotype - his bodily structure, or body type. According to McRobert, a wrist circumference of 17.5 cm or less indicates an ectomorphic somatotype. However, it is worth noting that it is not entirely correct to judge your body type based on one single sign. In fact, body type is determined not only by the thickness, but also by the length of the bones. Moreover, the classification of physique is based not only on the signs of the skeletal system, but also on other body systems (the main ones are taken into account in ours).
If we judge the type of person only by the bones, then it must be said that we need to study not only the thickness of the wrist, but also the thickness of the ankle. In a true ectomorph, the thickness of the wrist and ankle will be proportional. If a person has thin arm bones (assessed by the wrist), but the bones of the legs (assessed by the ankle) are not thin, then it is wrong to talk about an ectomorphic body type. By the way, about the thickness of the ankle: a girth of 22.5 cm and below indicates a thin bone. Moreover, if the difference between the thickness of the wrist and ankle is 5 cm, then we can say that the thickness of the bones of the arms and legs is proportional.
Thin bone and muscle growth
Let's return to the “folk wisdom” mentioned above: “a thin bone will not grow much meat.” Is the thickness of the bones the reason why muscles don't grow? No. Bone thickness is just an indicator of how physically powerful (strong) your body is. And if he is not like that (physically powerful, strong), then he grows poorly - this applies to both the thickness of the bones and the thickness of the muscles. There are, however, exceptions when there is good muscle mass on thin bones.
The power of the body depends on health and genetics, which, in principle, are interconnected.
Health is not only immunity, but also the general condition (functionality) of the body, that is, its performance. For example, lethargy, frailty, physical passivity - this is what is associated with poor health. The initial (primary) point in determining the level of health is the assessment of the cardiac system. Check with a cardiologist in a state of calm and physical activity the work of your cardiovascular system(). If there are certain violations or deviations from the norm, then consider that you will constantly have problems with muscle growth.
In turn, genetic power is either heredity (the genes of your parents) or the result of your own genes. Genes act on us through intermediaries, the main of which are hormones. Therefore, the genetic power of the body is controlled by the hormonal state. It is the activity of hormones that affects the growth of bone, muscle, and even fat tissue. Thin bone is most often evidence of insufficient secretion of sex hormones (insufficient specifically for physical strength (power); from the point of view of normal life activities, the level of hormones is, as a rule, quite normal).
Oddly enough, in this regard, you can fight genetics. After all, to increase the amount of sex hormones in the body, it is enough to train correctly. We have written more than once about the effect of training on the stimulation of sex hormones (testosterone). However, once again we emphasize the fundamental thing: it stimulates the secretion of testosterone and retains it best.
Hormonal levels are not everything for bone growth in breadth. Bone thickening (meaning normal, healthy, not pathological, such as osteosclerosis) is:
mechanical load + sufficient hormonal background + normal bone metabolism.
By the way, it is strength training that allows you to create the mechanical load that most stimulates the compaction (strengthening) of bones. As for metabolism in bone tissue, it is important to know the following: vital elements for the normal functioning of bones are calcium, phosphorus and vitamin D. Of course, other micro- and macroelements also play a significant role.
Thickness vs. bone length
If bone thickness is an indirect sign of predisposition to bodybuilding (associated rather with the general physical development person), then bone length is a parameter that can be directly related to the characteristics muscle growth. The fact is that muscle growth on bones of different lengths can be carried out in different ways.
Thus, a typical picture for short bones: the body of the muscle (abdomen, i.e. its main mass) sharpens at the ends of the bone, turning into the so-called muscle tails, which attach the muscle to the bone; the muscle tails are also pulled together by tendons.
A typical picture for long bones: the muscle body (abdomen) begins to sharpen relatively far from the ends of the bone and passes into muscle tails, then (towards the ends) muscle tails pass into tendons, with the help of which muscle group attached to the bone. It turns out that the bulk of the muscle is not concentrated along the entire length of the bone, if the bone is long. That is, there is no more meat on long bones than on short ones. But to increase meat on long bones, muscle growth must be significantly greater, which significantly lengthens the time required to solve the problem.
Results
1. If you are truly an ectomorph, then your bone thickness is a result of the rate of metabolic reactions in your body. It (this speed), as a rule, interferes with the normal gain of muscle mass. We call this part of ectomorphs hardgainers (ectomorphic hardgainers). At the same time, according to observations, for a certain part of ectomorphs, growing muscles is not a problem.
2. If you are not an ectomorph, but you have thin bones and do not gain mass well, then:
(a) you don't have enough physical strength(health) for muscle hypertrophy; you're probably having a hard time physical activity, it takes a long time to recover after them. Perhaps your health is not all right or you have low physical potential from birth (usually in such cases, in contrast, nature rewards you with high intellectual potential). Either way, you are a hard gainer.
(b) you have bad genetics for bodybuilding. Perhaps this is due to the "bad" type muscle fibers, insufficiency of some hormones (for example, testosterone) or excess of others (for example, estrogens), or some ectomorph traits passed on from mom or dad. In other words, you are also a hard gainer.
Links:
Human morphology: /Ed. B.A. Nikityuk, V.P. Chtetsova. Moscow State University Publishing House, 1990.