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Scientific Blackpill: Difference between revisions
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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%). | 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%). | ||
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 satellite cells in the muscle fibre. Those found to be "extreme | 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. | ||
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 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. | 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. | ||
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. | 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. | ||
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 | 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. | 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. | ||