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How do whites and blacks differ by muscle fiber and what does it mean for certain health outcomes? This is something I’ve touched on in the past, albeit briefly, and decided to go in depth on it today. The characteristics of skeletal muscle fibers dictate whether one has a higher or lower chance of being affected by cardiometabolic disease/cancer. Those with more type I fibers have less of a chance of acquiring diabetes while those with type II fibers have a higher chance of acquiring debilitating diseases. This has direct implications for health disparities between the two races.
Muscle fiber typing by race
Racial differences in muscle fiber typing explain differences in strength and mortality. I have, without a shadow of a doubt, proven this. So since blacks have higher rates of type II fibers while whites have higher rates of type I fibers (41 percent type I for white Americans, 33 percent type I for black Americans, Ama et al, 1985) while West Africans have 75 percent fast twitch and East Africans have 25 percent fast twitch (Hobchachka, 1988). Further, East and West Africans differ in typing composition, 75 percent fast for WAs and 25 percent fast for EAs, which has to do with what type of environment they evolved in (Hochhachka, 1998). What Hochhachka (1998) also shows is that high latitude populations (Quechua, Aymara, Sherpa, Tibetan and Kenyan) “show numerous similarities in physiological hypoxia defence mechanisms.” Clearly, slow-twitch fibers co-evolved here.
Clearly, slow-twitch fibers co-evolved with hypoxia. Since hypoxia is the deficiency in the amount of oxygen that reaches the tissues, populations in higher elevations will evolve hypoxia defense mechanisms, and with it, the ability to use the oxygen they do get more efficiently. This plays a critical role in the fiber typing of these populations. Since they can use oxygen more efficiently, they then can become more efficient runners. Of course, these populations have evolved to be great distance runners and their morphology followed suit.
Caesar and Henry (2015) also show that whites have more type I fibers than blacks who have more type II fibers. When coupled with physical inactivity, this causes higher rates of cancer and cardiometabolic disease. Indeed, blacks have higher rates of cancer and mortality than whites (American Cancer Society, 2016), both of which are due, in part, to muscle fiber typing. This could explain a lot of the variation in disease acquisition in America between blacks and whites. Physiologic differences between the races clearly need to be better studied. But we first must acknowledge physical differences between the races.
Disease and muscle fiber typing
Now that we know the distribution of fiber types by race, we need to see what type of evidence there is that differing muscle fiber typing causes differences in disease acquisition.
Those with fast twitch fibers are more likely to acquire type II diabetes and COPD (Hagiwara, 2013); cardiometabolic disease and cancer (Caesar and Henry, 2015); a higher risk of cardiovascular events (Andersen et al, 2015, Hernelahti et al, 2006); high blood pressure, high heart rate, and unfavorable left ventricle geometry leading to higher heart disease rates and obesity (Karjalainen et al, 2006) etc. Knowing what we know about muscle fiber typing and its role in disease, it makes sense that we should take this knowledge and acknowledge physical racial differences. However, once that is done then we would need to acknowledge more uncomfortable truths, such as the black-white IQ gap.
One hypothesis for why fast twitch fibers are correlated with higher disease acquisition is as follows: fast twitch fibers fire faster, so due to mechanical stress from rapid and forceful contraction, this leads the fibers to be more susceptible to damage and thus the individual will have higher rates of disease. Once this simple physiologic fact is acknowledged by the general public, better measures can be taken for disease prevention.
Due to differences in fiber typing, both whites and blacks must do differing types of cardio to stay healthy. Due to whites’ abundance of slow twitch fibers, aerobic training is best (not too intense). However, on the other hand, due to blacks’ abundance of fast twitch fibers, they should do more anaerobic type exercises to attempt to mitigate the diseases that they are more susceptible due to their fiber typing.
Black men with more type II fibers and less type I fibers are more likely to be obese than ‘Caucasian‘ men are to be obese (Tanner et al, 2001). More amazingly, Tanner et al showed that there was a positive correlation (.72) between weight loss and percentage of type I fibers in obese patients. This has important implications for African-American obesity rates, as they are the most obese ethny in America (Ogden et al, 2016) and have higher rates of metabolic syndrome (a lot of the variation in obesity does come down food insecurity, however). Leaner subjects had higher proportions of type I fibers compared to type II. Blacks have a lower amount of type I fibers compared to whites without adiposity even being taken into account. Not surprisingly, when the amount of type I fibers was compared by ethnicity, there was a “significant interaction” with ethnicity and obesity status when type I fibers were compared (Tanner et al, 2001). Since we know that blacks have a lower amount of type I fibers, they are more likely to be obese.
In Tanner et al’s sample, both lean blacks and whites had a similar amount of type I fibers, whereas the lean blacks possessed more type I fibers than the obese black sample. Just like there was a “significant interaction” between ethnicity, obesity, and type I fibers, the same was found for type IIb fibers (which, as I’ve covered, black Americans have more of these fibers). There was, again, no difference between lean black and whites in terms of type I fibers. However, there was a difference in type IIb fibers when obese blacks and lean blacks were compared, with obese blacks having more IIb fibers. Obese whites also had more type IIb fibers than lean whites. Put simply (and I know people here don’t want to hear this), it is easier for people with type I fibers to lose weight than those with type II fibers. This data is some of the best out there showing the relationship between muscle fiber typing and obesity—and it also has great explanatory power for black American obesity rates.
Conclusion
Muscle fiber differences between blacks and whites explain disease acquisition rates, mortality rates (Araujo et al, 2010), and differences in elite sporting competition between the races. I’ve proven that whites are stronger than blacks based on the available scientific data/strength competitions (click here for an in-depth discussion). One of the most surprising things that muscle fibers dictate is weight loss/obesity acquisition. Clearly, we need to acknowledge these differences and have differing physical activity protocols for each racial group based on their muscle fiber typing. However, I can’t help but think about the correlation between strength and mortality now. This obesity/fiber type study puts it into a whole new perspective. Those with type I fibers are more likely to be physically stronger, which is a cardioprotectant, which then protects against all-cause mortality in men (Ruiz et al, 2008; Volaklis, Halle, and Meisenger, 2015). So the fact that black Americans have a lower life expectancy as well as lower physical strength and more tpe II fibers than type I fibers shows why blacks are more obese, why blacks are not represented in strength competitions, and why blacks have higher rates of disease than other populations.The study by Tanner et al (2001) shows that there obese people are more likely to have type II fibers, no matter the race. Since we know that blacks have more type II fibers on average, this explains a part of the variance in the black American obesity rates and further disease acquisition/mortality.
The study by Tanner et al (2001) shows that there obese people are more likely to have type II fibers, no matter the race. Since we know that blacks have more type II fibers on average, this explains a part of the variance in the black American obesity rates and further disease acquisition/mortality.
Differences in muscle fiber typing do not explain all of the variance in disease acquisition/strength differences, however, understanding what the differing fiber typings do, metabolically speaking, along with how they affect disease acquisition will only lead to higher qualities of life for everyone involved.
References
Araujo, A. B., Chiu, G. R., Kupelian, V., Hall, S. A., Williams, R. E., Clark, R. V., & Mckinlay, J. B. (2010). Lean mass, muscle strength, and physical function in a diverse population of men: a population-based cross-sectional study. BMC Public Health,10(1). doi:10.1186/1471-2458-10-508
Andersen K, Lind L, Ingelsson E, Amlov J, Byberg L, Miachelsson K, Sundstrom J. Skeletal muscle morphology and risk of cardiovascular disease in elderly men. Eur J Prev Cardiol 2013.
Ama PFM, Simoneau JA, Boulay MR, Serresse Q Thériault G, Bouchard C. Skeletal muscle characteristics in sedentary Black and Caucasian males. J Appl Physiol 1986: 6l:1758-1761.
American Cancer Society. Cancer Facts & Figures for African Americans 2016-2018. Atlanta: American Cancer Society, 2016.
Ceaser, T., & Hunter, G. (2015). Black and White Race Differences in Aerobic Capacity, Muscle Fiber Type, and Their Influence on Metabolic Processes. Sports Medicine,45(5), 615-623. doi:10.1007/s40279-015-0318-7
Hagiwara N. Muscle fibre types: their role in health, disease and as therapeutic targets. OA Biology 2013 Nov 01;1(1):2.
Hernelahti, M., Tikkanen, H. O., Karjalainen, J., & Kujala, U. M. (2005). Muscle Fiber-Type Distribution as a Predictor of Blood Pressure: A 19-Year Follow-Up Study. Hypertension,45(5), 1019-1023. doi:10.1161/01.hyp.0000165023.09921.34
Hochachka, P.W. (1998) Mechanism and evolution of hypoxia-tolerance in humans. J. Exp. Biol. 201, 1243–1254
Karjalainen, J., Tikkanen, H., Hernelahti, M., & Kujala, U. M. (2006). Muscle fiber-type distribution predicts weight gain and unfavorable left ventricular geometry: a 19 year follow-up study. BMC Cardiovascular Disorders,6(1). doi:10.1186/1471-2261-6-2
Ogden C. L., Carroll, M. D., Lawman, H. G., Fryar, C. D., Kruszon-Moran, D., Kit, B.K., & Flegal K. M. (2016). Trends in obesity prevalence among children and adolescents in the United States, 1988-1994 through 2013-2014. JAMA, 315(21), 2292-2299.
Ruiz, J. R., Sui, X., Lobelo, F., Morrow, J. R., Jackson, A. W., Sjostrom, M., & Blair, S. N. (2008). Association between muscular strength and mortality in men: prospective cohort study. Bmj,337(Jul01 2). doi:10.1136/bmj.a439
Tanner, C. J., Barakat, H. A., Dohm, G. L., Pories, W. J., Macdonald, K. G., Cunningham, P. R., . . . Houmard, J. A. (2001). Muscle fiber type is associated with obesity and weight loss. American Journal of Physiology – Endocrinology And Metabolism,282(6). doi:10.1152/ajpendo.00416.2001
Volaklis, K. A., Halle, M., & Meisinger, C. (2015). Muscular strength as a strong predictor of mortality: A narrative review. European Journal of Internal Medicine,26(5), 303-310. doi:10.1016/j.ejim.2015.04.013
NotPoliticallyCorrect 
“Once this simple physiologic fact is acknowledged by the general public, better measures can be taken for disease prevention.”
What does the general public need to know ? It only matters to health professionals. What tells you health professionals don’t know or ignore it ?
And on muscular strength, none of your source says that differences in muscular strength due to muscular fiber typing cause mortality. There are many reasons why muscular strength can difer between two persons. It can be difference in androgens for instance.
You can’t do like peepee and say, “since fast twitch muscles are weaker (are they really ?) and weaker muscles are associated with mortality, then fast twitch muscles increase mortality”. That’s called syllogistic fallacy.
And of course, muscle fibers can’t account for a large part of the black-white life expectancy differences. All of the black American lifestyle diseases are relatively absent in West Africa to begin with, so you can’t write this post like there is a fatality or something and that blacks die younger just because it is in their nature to die younger.
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I know you will tell me about western diet. Well here in France, blacks are seldom obese or stff, same in the UK where there is data that you can find. So maybe it’s junk food and soul food, maybe it’s the US’s health system, maybe it’s something else specific to black Americans but I don’t see a worldwide pattern here.
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If the general public knew then better measures could be taken for disease prevention. Why should people wait to see a doctor to let them know that they have something hereditary that causes more problems than other people? If people knew while they were younger, prevention can start at an early age. People would make healthier choices and if the average black knew that their fiber typing may predispose them to higher disease rates than whites, maybe the disease rates will lower along with them getting a higher life expectancy.
I am making an educated guess. I know what different fiber types do and how it affects metabolism and cardio.
I don’t recall which of my references stated that more research needs to be done in regards to muscle fiber, mortality and strength. I’ll cite it later. However, the Araujo et al study showed that blacks had higher amounts of lean mass but lower strength when controlling for confounds. You can see in table 1 that blacks had higher grip strength but they have higher rates of mortality and disease. The authors were puzzled, however I stated why there is a difference. Muscle fibers. That’s really what it comes down to. That is a driver of muscular strength.
True. Obesity does mask androgens. But in the Tanner et al study they showed that the difference in obesity within and between populations came down to muscle fibers. People with more type I fibers have an easier time losing weight than people with type II fibers. And the fact that fibers differ by race shows, partly, why the races differ in obesity and disease.
Since they fire and contract more than slow twitch they get more tears. This is related to disease. Fast twitch fibers decrease muscular strength, therefore there is a relationship between muscle fibers, strength and mortality. It’s basic logic.
Right. It’s only a driver of it. Western diets drive the Western difference in disease and mortality. That’s a given, especially with what I’ve written over the past few months.
Worldwide patterns will emerge as countries become more and more Western. Once the Western diet arrives, there’s little that can be done to curb diseases of civilization.
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“If the general public knew then better measures could be taken for disease prevention. ”
The general public already knows that sedentarity and junk food skrews your health up. You want blacks to know they have to care more ? Well no problem, me already know we have to moisturize so we don’t mind being different. But in the end, it all comes down to individual responsibility to care for your health.
What the general public must know is that some people can’t afford fresh foods, have limited outdoors leisure option, live in areas where only junk food is available, are exposed to pollutants, can’t afford to see a doctor… And that these persons are disproportionaly black. That’s what the general public needs to know before anything else.
“I am making an educated guess.”
Alright, I’m waiting to see the educated guess of a specialist. No disrespect.
“Obesity does mask androgens. But in the Tanner et al study they showed that the difference in obesity within and between populations came down to muscle fibers. ”
I remember a study from the UK where black men (Caribbean as well as African) were much less obese than white. Here in France, I almost never see obese black dudes, I know it’s not robust but it’s heuristical.
“That’s a given, especially with what I’ve written over the past few months.”
Hum… Nothing that overshadows the importance of SES related factors.
“Once the Western diet arrives”
I’m more optimistic than you. There is no such thing as “the western diet”. I guess you mean processed food. Otherwise, developped countries in Europe and Asia don’t eat like Americans we eat our own foods. West Africans will keep on eating their local foods, although industrial meals will gain in importance. Maybe African Americans are victim of a mismatch between the West African foods their bodies are adapted to and the American ones they can access, this is another possibility too.
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How can I race reastically read this map ?
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Yes, I do want everyone to care about their health more. People should be aware that ancestry is correlated with a lot of negative variables. And by people knowing this, they won’t have to wait to go to their doctor to hear it. They can know from when they’re young and they can take steps to prevent disease.
I’m sure the general public knows this already. You know that I know that blacks and ‘Hispanics’ have higher levels of food insecurity and that that causes a lot of the variation in obesity in those populations. Junk food is cheaper than whole food, but I have seen a study from the FDA saying it really isn’t, you just need to know how to shop. I do agree that whole foods need to be cheaper. I’d even go the extra mile and say that we need to jack up the prices on garbage food.
I’m pretty sure that my hunch is correct.
We consider muscle fiber type distribution (type I or type II) to be an area of interest for future research. Muscle fiber type distribution has a major congenital component [36], is affected by physical activity [37], and is associated with isometric muscle strength [38] as well as obesity and type 2 diabetes [39, 40]. With promising techniques that measure muscle fiber type non-invasively [41], large cohort studies on how muscle fiber type distribution is associated with CVD are possible. It is also important to better understand how fitness interventions alter the CVD risk for individuals with different levels of baseline fitness.
Muscle strength in adolescent men and risk of cardiovascular disease events and mortality in middle age: a prospective cohort study
I should say, in equalized environments where food access is pretty much (largely) uniform. I know that black American men with more African ancestry are less likely to be obese due to specific genetic variants/physiological mechanisms. It’s very puzzling that black men are less likely to be obese than black women in America, despite having the same SES.
The Genetic Contribution of West-African Ancestry to Protection against Central Obesity in African-American Men but Not Women: Results from the ARIC and MESA Studies
I agree of course. However, even then, the general public should still be told “Those who have type II fibers are more likely to be obese than those with type I fibers. Further, African-Americans have more type IIx fibers which makes them more susceptible to obesity due to the fiber typing. Take care watching what you eat.” We could also get some damn nutrition education to kids at a young age and have some for parents that never had it.
But the fact of the matter is, the average white compared to the average black will be overweight/obese more often than not. And one of the main differences—the aetiology of this matter—is muscle fiber typing.
Anywhere a Western diet goes is where environmental mismatches occur. I've talked about the East Asian diet—the East Asian rice-eater paradox—it's nothing that's not explainable. They eat less processed carbs and more whole foods. However, as the Western diet takes hold, things change. Disease rates shoot up, diabesity rises. It's Western diets paired with Paleolithic genomes that are the problem.
JayMan covered this already:
A Fat World – With a Fat Secret?
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“Yes, I do want everyone to care about their health more. ”
Start advocating affordable healthcare first.
“People should be aware that ancestry is correlated with a lot of negative variables.”
We already know ancestry matters in health, but the discrepancies caused by ancestry aint large enough to be the object of national focus, SES related differences are.
“And by people knowing this, they won’t have to wait to go to their doctor to hear it.”
People have other things to do than following research and having opinion on not so well established facts.
” They can know from when they’re young and they can take steps to prevent disease.”
Told you, the issue is poverty, food deserts, food insecurity, unsafe public spaces, pollution and stuff before anything else.
“I’m sure the general public knows this already. You know that I know that blacks and ‘Hispanics’ have higher levels of food insecurity and that that causes a lot of the variation in obesity in those populations.”
Yah, they know but “Muh free market” “muh Mericuh” “muh public healthcare is communism” And all the retarded stuff that we only see in the US. You can’t say you want people to be healthy and support a system in which the market decides who lives or die at the same time.
” I’d even go the extra mile and say that we need to jack up the prices on garbage food.”
We have this in France, taxes on high sugar foods, alcohol and tobacco.
“I’m pretty sure that my hunch is correct.”
Maybe in America, but I can’t see an universal pattern among black populations.
“It’s very puzzling that black men are less likely to be obese than black women in America, despite having the same SES.”
Some genes have sex-specific expression. Blacks like thick or even big women so they don’t have the pressure to get thin.
” the general public should still be told “Those who have type II fibers are more likely to be obese than those with type I fibers. Further, African-Americans have more type IIx fibers which makes them more susceptible to obesity due to the fiber typing. Take care watching what you eat.””
We don’t give a damn unless we know our individual fiber typing. We don’t care about strangers or racial differences, it is a doctor’s concern not a layman one.
” It’s Western diets paired with Paleolithic genomes that are the problem.”
Yeah, and add a geographic mismatch to it and it probably increases risks. See, west Africans use palm oil for their daily cooking yet they have few of the health issues caused by palm oil so they probably adapted biologically. On the other hand, West Africans almost eat no red meat at all, so too much of it might be harmful, lactose intolerance is high in West and Central Africa too, and so on.
“JayMan covered this already:”
Please, bring me something solid.
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If people were to take the first step in caring for their health—that is, making healthy decisions—then one huge problem will be ameliorated. People eat trash food, then people get sick and get diabesity and other ailments. If only basic nutrition counseling was given earlier, maybe we wouldn’t be in this situation. But people need to take their health into their own hands first. People need healthy habits first. Most ailments we suffer and die from in America are very preventable and they mostly have to do with diet. People should take control of their health first, that’s what truly matters.
Let’s say that SES differences go away. Will disease acquisition suddenly drop? Or will people still have the same shitty eating habits? There is a direct relationship between high SES and having fewer instances of diabesity/other diseases within groups in America.
Let’s say we can push a button to make everyone in America have the same amount of money. Will there be any change in life expectancy and disease acquisition? I think not. Because people will still have the same shitty habits. Look at obesity in America. 67.3% for whites, 75.6% for blacks, and 77.9% for Hispanics. Sex breakdown by ethnicity: black women: 82 percent obese/overweight; black men 69.2 percent overweight/obese; white men 71.4 percent overweight/obese; white women 63.2 percent overweight and obese; ‘Hispanic’ men 78.6 percent overweight obese with 77.2 percent of ‘Hispanic’ women being overweight or obese. Whites eat a higher fat diet with a lower percentage coming from processed carbohydrates. Sure the SES factor is at play here since people in higher brackets can afford more expensive food, but I don’t think this gap would change too much if SES were equalized throughout the country.
This is directly related to my career and is why I research it. My clients will hear this information and I will direct them to their doctor. My opinion is backed by scientific data.
I agree. I’d like nothing more for super-sized drinks, things with added sugar, and garbage advertisements to be gone. But we don’t live in that kind of world and the only thing we can do is educate people—especially in low-income areas.
Insurance companies should be able to compete across state lines to drive down the costs of insurance—something Trump was going to do (but, predictably, went back on that)—but he, of course, stuck with Obamacare. There are different ways to implement free market healthcare.
The Founders supported the liberty behind free market capitalism. But, clearly, people with too much liberty make shitty life choices. I believe we need some government intervention in regards to food advertisement and monitoring what goes into our food.
France has the lowest obesity rate in the OECD but rates are rising. One in 10 French people are overweight with over 40 percent being obese and overweight. Good, but as predicted, rates are rising. Wonder why…
The pattern is: Western diets+blacks=high rates of obesity and disease. Muscle fiber tying plays a role in this.
Yep. It’s also seen as a ‘protective factor’ against eating and body image pathology in American black women.
Ethnic differences in preferences for female weight and waist-to-hip ratio: a comparison of African-American and White American college and community samples.
The whole point is to tell everyone to watch what they eat because certain people are more susceptible.
Palm oil is similar to coconut oil in that it doesn’t burn. Some drink milk and animal blood and rarely meat ,right? There are benefits and drawbacks of palm oil, however.
Countries with a Western diet are more likely to be obese. Shocking. Obesity is on the rise wherever Western diets go. The number of obese people in China surpassed the US. What’s that tell you?
This seems to be a drawback of a country becoming more modern—a higher percentage of the population becoming obese.
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This is a fantastic explanation of some of the physical differences between blacks and human beings, bravo. I commend you, Sir.
Many people just choose to forget he fact that, during slavery, we practiced selective breeding much like the Spartans did. We had no need for weak slaves, after all.
Take a look at the apes still residing back in Africa, for example.
Would they be decent candidates for the NFL, NBA? Of course not, and not just due to their malnourishment and lack of civilization.
I have always claimed, which muscle controls all others? The brain.
That is precisely why blacks just cannot seem to make it in any modern human civilization, no matter how we prop them up.
At least now, people are once again waking up to the truth of evolution and why it left blacks behind ages ago.
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Thanks for the compliment. I’m not so much interested in brain differences anymore. My main focus is on physiological and anatomic differences between the races. And blacks are human beings, being they are Homo sapiens as well.
I’m going to write something about this soon. From my research, I’ve not been able to find anything that verifies this.
Obviously not. Black Americans are also around 22 percent European so that helps as well.
Correct. Though there is an intricate relationship with the central nervous system (CNS), the brain and muscle control.
African HDI (human development index) is rising, and I believe that it’s due to the Chinese projects going on there. I’m sure Afrosapiens can tell you more there, he’s more knowledgeable there than I.
What? How does evolution “leave organisms behind”? Evolution doesn’t stop. It’s not ongoing process. Sure, successful species reach stasis when they become adapted to their environment. However, evolution occurs faster in the tropics.
Can you explain the biological mechanisms that has evolution stop and “leave organisms behind”?
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I sure can, good sir.
All human beings have 1-4% Neanderthal DNA today.
There is only one single group that missed out on our interbreeding, which sparked our human evolution: African blacks.
They simply cannot gain this DNA in their offspring by mating with us, it just doesn’t work.
Since Neanderthals are now long extinct, blacks have lost out on their chance for human evolution, forever.
I had to be brief, if I can go into further detail later if you require.
Blacks are simply not Homo sapiens. They never were, and they never will be, period.
Research homo naledi.
Our differences go far, far deeper than biological.
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You know that Chris Stringer—one of the originators of the OoA hypothesis—has ‘rethunk Out of Africa‘ due to the findings of our interbreeding with other hominins, right?
‘Rethinking Out of Africa’ doesn’t mean what you think it means, however.
Please do. Also, bring references for your claims.
You seem confused. Homo sapiens arose between 200-300 kya in Africa. This is not up for debate.
I’ve been keeping up with recent research. What about it?
Most of what you said is wrong.
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