Scientific Blackpill: Difference between revisions

Jump to navigation Jump to search

Scientific Blackpill (edit)

Revision as of 12:40, 16 October 2020

2,607 bytes added ,  16 October 2020
m
→‎A man's muscle building capacity is primarily determined by genetics
mNo edit summary
Line 3,375: Line 3,375:
<div class="navbar" style="padding-left: 4px; margin-top: 3px; background: #EAEAEA; color: #555; border-top: 2px solid #444; border-bottom: 1px solid #444; font-size: 13px">[[#A_man.27s_muscle_building_capacity_is_primarily_determined_by_genetics|permalink]] | [[#tocBody|category: Body]] | [[#tocA_man.27s_muscle_building_capacity_is_primarily_determined_by_genetics|table of contents]]</div>
<div class="navbar" style="padding-left: 4px; margin-top: 3px; background: #EAEAEA; color: #555; border-top: 2px solid #444; border-bottom: 1px solid #444; font-size: 13px">[[#A_man.27s_muscle_building_capacity_is_primarily_determined_by_genetics|permalink]] | [[#tocBody|category: Body]] | [[#tocA_man.27s_muscle_building_capacity_is_primarily_determined_by_genetics|table of contents]]</div>


There is significant evidence that an individual's muscle building genetics is the major determinant of an individual's muscle building capabilities.
There is significant evidence that an individual's muscle-building genetics is the primary determinant of an individual's muscle-building capabilities.
Carpinelli (2017), reviewed key studies regarding this topic, concluding that the research provided strong evidence for individual genetic variance being the largest factor in how one responds to strength training, as compared to differences in exercise programming, effort, diet and other factors.
He noted that Hubal et al. (2005), had earlier conducted a study on a mixed-gender cohort (N = 585) who performed an identical resistance training protocol, 3x a week for three months. It was found that the average increase in muscle growth, as measured via MRI, was 18.9%, but this varied between the subjects within a vast range, with one individual even losing muscle in response to the strength training regimen (-2%) whilst one subject gained muscle at a rate more than three times the average (+59%).


Carpinelli (2017), reviewed key studies regarding this topic, stating that the research provided strong evidence for individual genetic variance being the largest factor in how one responds to strength training, as compared to differences in exercise programming, etc.
Further on this topic, Petrella et al. (1985) recruited 66 adults and divided them into separate groups based on age, subjecting them to a program that was based on lower body exercises. They found evidence of a disparate response to resistance training among the individuals involved, congruent with the findings above, but what was also significant was that they identified a strong relationship regarding response to resistance training and individual differences in the population of satellite cells in the muscle fibre. Those found to be "extreme responders" were also found to exhibit a much greater proliferation of the satellite cell pool, as compared to those who exhibited more modest muscle growth.


He noted that Hubal et al. (2005), had earlier conducted a study on a mixed-gender cohort (N = 585) who performed an identical resistance training protocol, 3x a week for three months. It was found that the average increase in muscle growth, as measured via MRI, was 18.9%, but this varied between the subjects within a very broad range, with one individual actually losing muscle (-2%) and one gaining muscle at rate more than 3 times the average (+59%).
One of the other factors that likely moderates individual heterogeneity in responses to resistance training is androgen receptor density. Various cell types in disparate regions of the human body contain receptors to which androgens (male sex hormones, such as testosterone) activate, and these receptors then regulate gene expression and possibly influence muscle growth through non-genomic factors also. An individual's genetic differences in sensitivity to circulating androgens have a very large influence on pubertal development and their overall physical phenotype.


Further on this topic, Petrella et al. (1985) recruited 66 adults and divided them into separate groups based on age, subjecting them to a program that was based on lower body exercises. They found evidence of a disparate response to resistance training among the individuals involved, congruent with the findings above, but what was also significant, was that they identified a strong relationship regarding response to resistance training and individual differences in population of [https://web.archive.org/web/20070307094634/http://www.brown.edu/Courses/BI0032/adltstem/sc.htm satellite cells] in the muscle fibre. Those found to be "extreme responders" were also found to exhibit a much greater proliferation of the satellite cell pool, as compared to those who exhibited more modest muscle growth.
In an attempt to determine how important individual differences in androgen receptor content in the muscle was to determining response to resistance training, Morton et al. (2018) examined 49 resistance-trained young men, who were assigned to either a high rep or low rep group, both groups were also administered two doses of 30 g of whey protein isolate per day.
The subjects hormone levels were monitored post pre and post-intervention via analysis of circulating levels of hormones in the blood. The techniques of immunoassay and immunoblot determined differences in androgen receptor content. Monitoring changes in muscle mass, as determined by muscle biopsy, again strong evidence of considerable individual variation in response to resistance training was found, with some even losing muscle in response to the training, and some making large gains.
Significantly, they found evidence that circulating levels of male hormones (within the physiologically normal range; excluding the effects of performance-enhancing drugs) did not appear to have a large effect on the individual's response to resistance training. Instead, they found that one of the main factors that determined individual response to resistance training was likely intramuscular androgen receptor content and density. This also means that even one's response to potent exogenous substances designed to enhance muscular growth, such as androgenic-anabolic steroids (AAS), is also substantially determined by genetics.


One of the other factors that likely moderates individual heterogeneity in responses to resistance training is [https://en.wikipedia.org/wiki/Androgen_receptor androgen receptor] density. Various cell types in disparate regions of the human body contain receptors to which androgens (male sex hormones, such as testosterone) activate, and these receptors then regulate gene expression and possibly also influence muscle growth through non-genomic factors also. An individual's genetic differences in sensitivity to circulating androgens has a very large influence on pubertal development, and their overall physical phenotype.
Another factor that determines an individual's response to strength training and their maximal muscle building capacity is skeletal frame size. There are large correlations between the thickness width of certain joints in the body and total fat-free mass, particularly wrist thickness, as this is positively correlated with lean body mass but negatively correlated with total body fat (Chumlea et al., 2001). It is even possible to calculate one's maximal muscular potential with a rough degree of accuracy from the thickness of one's wrists and ankles (Nuckols, G., 2015).  
 
As bone circumference is mostly heritable and also generally fixed by the end of adolescence in any case (Clark, J., 1955), a frame size significantly lower than average is a significant factor limiting the quality of the response to resistance training, especially if commenced in adulthood.
In an attempt to determine how important individual differences in androgen receptor content in the muscle was to determining response to resistance training, Morton et al. (2018) examined 49 resistance trained young men, who were assigned to either a high rep or low rep group, both groups were also administered 2 doses of 30 g of whey protein isolate per day.
There are also substantial racial differences in average bone thickness and density, with blacks having the thickest bones, then whites; with Asians and south Asians having thinnest and weaker bones on average (Zengin et al., 2016, Cong & Walker, 2014).
 
Thus, one could also expect the typical response to resistance training to vary somewhat by race, with their being more 'easy gainers' found among blacks and more 'hard gainers' found among east and south Asians.  
The subjects hormone levels were monitored post pre and post intervention via analysis of circulating levels of hormones in the blood. Differences in androgen receptor content was determined by the techniques of immunoassay and immunoblot. Monitoring changes in muscle mass, as determined by muscle biopsy, again strong evidence of large individual variation in response to resistance training was found, with some even losing muscle in response to the training, and some making large gains.
 
Significantly, they found evidence that circulating levels of male hormones (within the physiologically normal range; obviously excluding the effects of performance enhancing drugs) didn't appear to have a large affect on the individuals response to resistance training. Notably, they found that one of the main factors that determined individual response to resistance training was likely intramuscular androgen receptor content and density.


<span style="font-size:125%">'''Quotes:'''</span>
<span style="font-size:125%">'''Quotes:'''</span>
Line 3,402: Line 3,403:
* Petrella JK1, Kim JS, Mayhew DL, Cross JM, Bamman MM. 1985. ''Potent myofiber hypertrophy during resistance training in humans is associated with satellite cell-mediated myonuclear addition: a cluster analysis.'' J Appl Physiol:104(6):1736-42. [[https://www.ncbi.nlm.nih.gov/pubmed/18436694 Abstract]]
* Petrella JK1, Kim JS, Mayhew DL, Cross JM, Bamman MM. 1985. ''Potent myofiber hypertrophy during resistance training in humans is associated with satellite cell-mediated myonuclear addition: a cluster analysis.'' J Appl Physiol:104(6):1736-42. [[https://www.ncbi.nlm.nih.gov/pubmed/18436694 Abstract]]
* Morton RW, Sato K, Gallaugher MPB, Oikawa SY, McNicholas PD, Fujita S, Phillips SM. 2018. ''Muscle Androgen Receptor Content but Not Systemic Hormones Is Associated With Resistance Training-Induced Skeletal Muscle Hypertrophy in Healthy, Young Men.'' Front. Physiol. [[https://www.frontiersin.org/articles/10.3389/fphys.2018.01373/full FullText]]
* Morton RW, Sato K, Gallaugher MPB, Oikawa SY, McNicholas PD, Fujita S, Phillips SM. 2018. ''Muscle Androgen Receptor Content but Not Systemic Hormones Is Associated With Resistance Training-Induced Skeletal Muscle Hypertrophy in Healthy, Young Men.'' Front. Physiol. [[https://www.frontiersin.org/articles/10.3389/fphys.2018.01373/full FullText]]
* Chumlea WC, Wisemandle W, Guo SS, & Siervogel R. 2001. ''Relations between frame size and body composition and bone mineral status.'' Am J Clin Nutr:75:1012–6.[[https://europepmc.org/article/med/12036807 Abstract]]
*Nuckols, G. 2015. ''YOUR Drug-Free Muscle and Strength Potential: Part 1.'' [[https://www.strongerbyscience.com/your-drug-free-muscle-and-strength-potential-part-1/ Article]]
* Clark, PJ. 1955. ''The Heritability of Certain Anthropometric Characters as Ascertained from Measurements of Twins''. Institute of Human Biology, University of Michigan, Ann Arbor, Michigan. [[https://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC1716621&blobtype=pdf Fulltext]]
* Zengin AR, Pye SR, Cook MJ, Adams JE, Wu FCW, O' Neill TW & Ward KA. 2016. ''Ethnic differences in bone geometry between White, Black and South Asian men in the UK.'' Bone:91:180–185. [[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5004623/ FullText]]
* Cong E & Walker MD. 2014. ''The Chinese skeleton: insights into microstructure that help to explain the epidemiology of fracture''. Bone Research:2:14009 [[https://www.nature.com/articles/boneres20149 FullText]]


===<span style="font-family:'Linux Libertine, Georgia, Times, serif'; font-size: 24px; line-height: 1.2; font-weight: normal;" id="Among_male_university_students.2C_only_cues_of_physical_dominance_over_other_men_predicted_their_mating_success">Among university students, only physical dominance over other men predicted mating success</span>===
===<span style="font-family:'Linux Libertine, Georgia, Times, serif'; font-size: 24px; line-height: 1.2; font-weight: normal;" id="Among_male_university_students.2C_only_cues_of_physical_dominance_over_other_men_predicted_their_mating_success">Among university students, only physical dominance over other men predicted mating success</span>===
Retrieved from "https://incels.wiki/w/Special:MobileDiff/55790"

Navigation menu