Fitness Series Season 01 Episode 02
Genetics:
South Asians have a mixed genetic background, with ancestry from West Eurasia and East Eurasia. This may influence things like muscle fiber types and body composition.
Research is ongoing, but some genes may be linked to higher risk of certain diseases in South Asians, like type 2 diabetes.
Fitness:
Studies suggest South Asians may be less likely to meet recommended exercise guidelines compared to other groups.
Cultural preferences and social norms may influence exercise choices, with walking being a popular activity.
Important Ideas and References
1. Role of Genetics in Physical Traits and Health
- Genetics significantly influence physical traits, muscle mass, fat accumulation, and response to diet and exercise.
- Reference: [Visscher, P. M., Hill, W. G., & Wray, N. R. (2008). Heritability in the genomics era — concepts and misconceptions. Nature Reviews Genetics*, 9(4), 255-266.](https://doi.org/10.1038/nrg2322)
2. Evolution and Natural Selection
- Evolution through natural selection has shaped human traits over millions of years.
- *Reference:* [Darwin, C. (1859). On the Origin of Species by Means of Natural Selection. London: John Murray.](https://www.gutenberg.org/ebooks/2009)
3. Geographical Influence on Physical Characteristics
- Bergmann’s and Allen’s rules explain variations in body types based on climate.
- Reference: [Allen, J. A. (1877). The influence of physical conditions in the genesis of species. Radical Review, 1, 108-140.](https://archive.org/details/radicalreview01assogoog/page/n138/mode/2up)
- https://www.unl.edu/rhames/courses/ppoint/heat-110.pdf
4. Genetic Influence on Muscle Fiber Composition
- [Specific genes influence muscle fiber types, such as fast-twitch fibers, impacting strength and speed.](https://onlinelibrary.wiley.com/doi/10.1002/bies.20061)
- Reference: [MacArthur, D. G., & North, K. N. (2004). A gene for speed? The evolution and function of α-actinin-3. BioEssays, 26(7), 786-795.](https://doi.org/10.1002/bies.20061)
5. Genetic Predisposition to Type 2 Diabetes in South Asians
- Higher prevalence of type 2 diabetes due to genetic traits related to insulin sensitivity and glucose metabolism.
- Reference: [Mohan, V., Deepa, R., Deepa, M., Somannavar, S., & Datta, M. (2005). A simplified Indian Diabetes Risk Score for screening for undiagnosed diabetic subjects. Journal of the Association of Physicians of India, 53, 759-763.](https://pubmed.ncbi.nlm.nih.gov/16334618/)
6. Physical Characteristics of South Asians
- Smaller bone structure, narrow shoulders and hips, short limbs, and lower bone density compared to other populations.
- Reference: [Misra, A., & Khurana, L. (2011). Obesity and the metabolic syndrome in developing countries. The Journal of Clinical Endocrinology & Metabolism, 93(11_supplement_1), s9-s30.](https://doi.org/10.1210/jc.2008-1595)
7. ACTN3 Gene and Athletic Performance
- The ACTN3 gene, specifically the R577X variant, is linked to muscle performance and athletic ability.
- Reference: [Yang, N., MacArthur, D. G., Gulbin, J. P., Hahn, A. G., Beggs, A. H., Easteal, S., & North, K. (2003). ACTN3 genotype is associated with human elite athletic performance. American Journal of Human Genetics, 73(3), 627-631.](https://doi.org/10.1086/377590)
8. Lower Birth Weight in South Asians
- Often related to maternal nutrition during pregnancy, impacting overall health and metabolic activities later in life.
- Reference: [Bhargava, S. K., Sachdev, H. S., Fall, C. H., Osmond, C., Lakshmy, R., Barker, D. J., ... & Biswas, S. K. (2004). Relation of serial changes in childhood body-mass index to impaired glucose tolerance in young adulthood. New England Journal of Medicine, 350(9), 865-875.](https://doi.org/10.1056/NEJMoa035698)
9. Testosterone Levels and Myostatin
- Testosterone and trenbolone enanthate increase mature myostatin protein expression despite increasing skeletal muscle hypertrophy and satellite cell number in rodent muscle
[https://doi.org/10.1111/and.12622](https://doi.org/10.1111/and.12622)
10. Historical Influence on Physical Traits and Health
Evolutionary explanation of human females body fatredistribution
- Reference:https://www.semanticscholar.org/paper/Evolutionary-explanation-of-human-females-body-fat-Abrahim/f0a1e30cf0f29af90bdb7befe8d622916135e90c - [doi:10.1093/emph/eoab030](https://www.semanticscholar.org/paper/Evolutionary-explanation-of-human-females-body-fat-Abrahim/f0a1e30cf0f29af90bdb7befe8d622916135e90c)