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African Runners Dominance in Distance Running

African Runners Dominance in Distance Running . Steve Magness. Objectives. Dominance Genetics Physiology Cultural and Social Factors Training. Dominance. Out of the Distance events 800 1500 3,000m steeple 5,000 10,000 Marathon

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African Runners Dominance in Distance Running

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  1. African Runners Dominance in Distance Running Steve Magness

  2. Objectives • Dominance • Genetics • Physiology • Cultural and Social Factors • Training

  3. Dominance • Out of the Distance events • 800 • 1500 • 3,000m steeple • 5,000 • 10,000 • Marathon • Kenyans occupy over 50% of the top 20 times in each event. Larsen, H. Kenyan dominance in distance running. Comparative Biochemistry and Physiology Part A 136 (2003) 161–170

  4. Best Non-African Performance • Steeple • 163rd best performance (Bob Tahri- France)* • 5k • 98th best performance (Craig Mottram-Australia)* • 10k • 106th best performance (Arturo Barrios- Mexico) • Marathon • 18th best performance (Ronaldo da Costa-Brazil) *There has been a faster non-african, but he later tested positive for drugs.

  5. Time Comparison

  6. How Dominant are they? • Depth • Number of sub 2:20 marathoners Tanser, T. (2008) More Fire. Westholme Publishing, Pennsylvania.

  7. Tribal Dominance • Kenya • 81% of top Kenyan Runners come from the Rift valley • Kalenjin tribe represents ~75% of all members competing on national teams. • 2007 world Cross country championships • 7 of 12 individual medals went to Kalenjins. • Ethiopia • 38% of the elite marathoners were from the Arsi region, which only makes up less than 5% of the total Ethiopian population. Scott, R. et al. Genetics and the success of East African distance runners. International SportsMed Journal. Vol. 7 No.3 2006

  8. Rift Valley phenomenon • Proof of superior genetics? • Rift Valley is at high altitude. • However, Rift Valley extends 3,000mi • Includes many countries that have slow national records in distance events • Some of Kenya’s top runners ever did not come from the rift valley • Two 10k gold medalist, one WR holding 5k runner, and one marathon gold medalist • Several Kenyan villages/towns at “ideal” altitudes have produced no world class runners.

  9. Genetics • Mitochondrial DNA • Inherited from mother, so can trace back and create a DNA tree. • Mitochondrial DNA influences aerobic performance.

  10. Mitochondrial DNA-Ethiopians • Shows a wide and varied distribution. • Endurance athletes did not differ much from the general population. Scott, R. et al. Genetics and the success of East African distance runners. International SportsMed Journal. Vol. 7 No.3 2006

  11. Mitochondrial DNA-Ethiopians • “This finding does not support the hypothesis that the Ethiopian population from which the athletes are drawn have remained genetically isolated in East Africa but shows that they have undergone migration events during the age of the species.  This is in contrast to the possibility that Ethiopian athletes have maintained and further developed the ancestral endurance phenotype through having remained isolated in the East African highlands” Scott, R. et al. Genetics and the success of East African distance runners. International SportsMed Journal. Vol. 7 No.3 2006

  12. Y-Chromosome- Ethiopians • Y-chromosome is the male equivalent to the mitochondria DNA. • Found variation between population and elite endurance athletes Scott, R. et al. Genetics and the success of East African distance runners. International SportsMed Journal. Vol. 7 No.3 2006

  13. “despite the finding of a potential effect of the Y chromosome on endurance performance, the Y chromosome results show similar levels of diversity to those found using mtDNA.  In addition, it can be seen from Figure 3 that a significant number of the athletes trace part of their male ancestry to outside Africa at some time during the age of our species.  Studies using non-recombinant markers are concordant in their finding that the elite Ethiopian athletes show similar genetic diversity to the general population, and can trace their ancestry to diverse populations, rather than a uniquely ‘highland African’ population “ Scott, R. et al. Genetics and the success of East African distance runners. International SportsMed Journal. Vol. 7 No.3 2006

  14. ACE gene • Angiotensin converting enzyme • One form is associated with endurance performance • ACE gene- Kenyan Runners • 29% of controls from Kenya had the gene • 17% of international Kenyan athletes had the gene Scott RA, Moran C, Wilson RH, et al.  No association between Angiotensin Converting Enzyme (ACE) gene variation and endurance athlete status in Kenyans.  Comp Biochem Physiol A Mol Integr Physiol 2005;141(2):169-175.

  15. Physiology of African Runners • Vo2max • Lactate • Fractional Utilization of VO2max • Running Economy • Lower leg thickness • Muscle Fiber Type • Enzyme concentration • Capillary Density

  16. VO2max • Kenyan Elites- 79.9 • Scandinavian elites- 79.2 • No difference between kenyan boys and Scandinavian boys Saltin B, Larsen H, Terrados N, et al. Aerobic exercise capacity at sea level and at altitude in Kenyan boys, junior and senior runners compared with Scandinavian runners. Scand J Med Sci Sports 1995;5(4):209-221.

  17. Lactate • Saltin found • Lower lactate levels across submax to high intensity velocities. • Blood Ammonia response after maximal intensity was 1/3 to ½ as high for Kenyan elites compared to Scandinavian elites. • Larsen found • lower blood ammonia concentrations at submaximal intensities for Kenyan boys compared to Danish boys. Saltin B, Larsen H, Terrados N, et al. Aerobic exercise capacity at sea level and at altitude in Kenyan boys, junior and senior runners compared with Scandinavian runners. Scand J Med Sci Sports 1995;5(4):209-221. -Larsen, H. Kenyan dominance in distance running. Comparative Biochemistry and Physiology Part A 136 (2003) 161–170

  18. Fractional Utilization of VO2max • Ability to use a larger % of VO2max over race distance • Kip Keino able to run 10k at 97-98%Vo2max • Coetzer et al.- compared 10k race pace with VO2 of the athlete running at that pace on treadmill and found that African runners raced 10 km at a higher percentage of their VO2max than white runners. Larsen, H. Kenyan dominance in distance running. Comparative Biochemistry and Physiology Part A 136 (2003) 161–170 BILLAT, V. et al.Training and Bioenergetic Characteristics in Elite Male and Female Kenyan Rusnners. Med. Sci. Sports Exerc. Vol. 35, No. 2, pp. 297-304. 2003.

  19. Running Economy Weston et al. (2000). Running Economy of African and Caucasian Runners. Med. Sci. Sports Exercise. Vol 32. No. 6. pg. 1130-34.

  20. Running Economy • Other studies showing Running Economy differences • Saltin- Kenyans had better economy than Scandinavian elite runners. • Larsen- • untrained Kenyan boys from the Nandi tribe had better running economy than in untrained Danish boys. Saltin B, Larsen H, Terrados N, et al. Aerobic exercise capacity at sea level and at altitude in Kenyan boys, junior and senior runners compared with Scandinavian runners. Scand J Med Sci Sports 1995;5(4):209-221. -Larsen, H. Kenyan dominance in distance running. Comparative Biochemistry and Physiology Part A 136 (2003) 161–170

  21. Reason for difference? Saltin, B. (2003). The Kenya Report. New Studies in Athletics. Vol 18, no.2, pg 15-24.

  22. Low mass at extremes • volume and the mean thickness- 15-17% less for Kenyans • Body Composition • Kenyan boys were 5cm shorter and 12kg lighter than Danish boys. • Kenyan boys had 2cm longer legs and 1cm longer lower legs. • Saltin conclusion: • “The optimal body shape of a distance runner with respect to running economy is a combination of small height, slender body shape with the legs representing a large fraction of the body height and thin lower legs.”

  23. Biomechanics De Heer,H. et al. Anthropometric, gait and strength characteristics of Kenyan distance runners. Journal of Sports Science and Medicine (2008) 7, 499-504.

  24. Muscle Fiber Type Saltin B, Kim CK, Terrados N, et al.  Morphology, enzyme activities and buffer capacity in leg muscles of Kenyan and Scandinavian runners.  Scand J Med Sci Sports 1995;5(4):222-30.

  25. Muscle Fiber TypeQuadriceps Femoris Saltin, B. (2003). The Kenya Report. New Studies in Athletics. Vol 18, no.2, pg 15-24.

  26. Oxidative Enzyme Concentration • CS activity • Positive relationship between CS concentration and running performance • Lower in Kenyans in boys • No difference between Kenyan and Scandinavian Elites. Saltin, B. (2003). The Kenya Report. New Studies in Athletics. Vol 18, no.2, pg 15-24. Saltin B, Kim CK, Terrados N, et al.  Morphology, enzyme activities and buffer capacity in leg muscles of Kenyan and Scandinavian runners.  Scand J Med Sci Sports 1995;5(4):222-30.

  27. HAD enzyme concentration HAD enzyme concentration- indicator of ability to utilize fat as fuel. Saltin, B. (2003). The Kenya Report. New Studies in Athletics. Vol 18, no.2, pg 15-24.

  28. Capillaries • Elites • Kenyan elites only had a slight tendency for more capillaries. • Untrained • No difference between Danish boys and Kenyan Village boys. Saltin, B. (2003). The Kenya Report. New Studies in Athletics. Vol 18, no.2, pg 15-24. Larsen, H. Kenyan dominance in distance running. Comparative Biochemistry and Physiology Part A 136 (2003) 161–170

  29. Lactate Transporters • Compared MCT 1 and MCT 4 concentrations between White and African runners. • MCT1- influx of lactate into ST fibers • MCT4- efflux of lactate out of FT fibers. • No difference in either. • Problem with study- not very fast runners in either group (~34min 10k) Harley, Y. et al. Skeletal muscle monocarboxylate transporter content is not different between black and white runners. Eur J Appl Physiol (2009) 105:623–632

  30. Closer look of Comparison by Saltin et al.

  31. Cultural and Social Factors • Altitude • Psychological Factors • Diet • Money • Active Lifestyle

  32. Altitude and Sea level comparison 10k Avg. Difference: 13.33sec

  33. Altitude and Sea Level comparison • NCAA altitude adjustment for 1,700m • 10k- 71.58 seconds (for a 28:45 10k) • Compared to a difference of 13.33sec for the three 3 Kenyan runners • What does this mean? • African’s born at altitude can train at much higher intensities compared to western athletes. • Therefore, negative consequences of altitude (decrease cardiac output, vo2max, training velocity, and muscle recruitment) don’t affect them as much.

  34. Altitude NOT the only answer • Where are the Nepal and Andean runners? • Kayser et al. found that Nepal Sherpas had lower VO2max and mitochondrial density than Caucasian climbers. Hamilton, B. East African running dominance: what is behind it? Br J Sports Med. 2000 Oct;34(5):391-4.

  35. Psychological Factors • Stereotype threat • “what we believe to be true about our genetic make up may be more important than what is actually true.” • “Regardless of the possible existence of physiological advantages in East African runners, belief that such differences exist creates a psychological atmosphere that can have significant consequences on performance”

  36. Psychological Factors • Aura of Invincibility • Not the first time it has happened in running • Early 1900’s- Scandinavian Runners won 28 out of 36 possible medals over 5k and 10k in the Olympics. • “of all the Kenyan tribes, the Kalenjin had the highest achievement orientation” Hamilton, B. East African running dominance: what is behind it? Br J Sports Med. 2000 Oct;34(5):391-4.

  37. Diet • Average intake • 67% carbohydrate • 15% protein • 17% fat Fudge, B. et al. Evidence of negative energy balance using doubly labelled water in elite Kenyan endurance runners prior to competition. British Journal of Nutrition. 2006, 95, 59-66.

  38. Diet • Most were in a negative energy balance

  39. Money Motivation for Running • Running is there way out • Few job choices • Ex: Teachers make on average $580 per year • 40% of the total Kenyan population are unemployed • at least 50% live below the poverty line. Onywera VO, Scott RA, Boit MK, et al. Demographic characteristics of elite Kenyan endurance runners.  J Sports Sci 2006; 24(4):415-422.

  40. Active Lifestyle • ““Kenyans start an official training already from the 85-90% of their top level, white people from 30-50%. (white runners) must spend 10-12 years of his life before reaching the same level that the Kenyan has at his beginning.” Renato Canova

  41. Active Lifestyle- Kenyans Onywera VO, Scott RA, Boit MK, et al. Demographic characteristics of elite Kenyan endurance runners.  J Sports Sci 2006; 24(4):415-422.

  42. Active Lifestyle-Ethiopians Distance Traveled to School Method of Transportation Dark black- Transportation Light black- Run (5-20km is the light black) Scott RA, Georgiades E, Wilson RH, et al.  Demographic characteristics of elite Ethiopian endurance runners.  Med Sci Sports Exerc 2003;35(10):1727-1732.

  43. Active Lifestyle De Heer,H. et al. Anthropometric, gait and strength characteristics of Kenyan distance runners. Journal of Sports Science and Medicine (2008) 7, 499-504.

  44. Active Lifestyle • Could genetics and/or Altitude be clouding the picture? • The Tribes where the majority of the best runners come from are also happen to be the more rural areas where a more active lifestyle is required. Hamilton, B. East African running dominance: what is behind it? Br J Sports Med. 2000 Oct;34(5):391-4.

  45. Training • Trainability • Comparison of Training between Western and African Runners • Lactate Response during a Race

  46. Trainability • Larsen and Saltin compared trainability of untrained kids to see if African response to training was more. • Both groups did the same training for 12 weeks Larsen, H.B. et al. Training response of adolescent Kenyan town and village boys to endurance running. Scandinanivan Journal of Medicine and Science in Sports. In press, 2003. Saltin, B. (2003). The Kenya Report. New Studies in Athletics. Vol 18, no.2, pg 15-24.

  47. Trainability of kids • CS activity • No difference between Kenyan Village boys and Danish kids • HAD activity • No difference between Kenyan Village boys and Danish kids • Blood Lactate • Kenyan Village boys had initial lower lactate levels (due to better running economy) but training decreased lactate levels to the same extent as Danish kids. Larsen, H.B. et al. Training response of adolescent Kenyan town and village boys to endurance running. Scandinanivan Journal of Medicine and Science in Sports. In press, 2003. Saltin, B. (2003). The Kenya Report. New Studies in Athletics. Vol 18, no.2, pg 15-24.

  48. Trainability of kids • Performance • Who knows… • They only measured 5k performance POST training. • “Kenyan boys from the rural area having the same initial fitness level (maximal oxygen uptake) as Danish boys ran 10% faster in a 5000 metres competition after performing 12 weeks of standardised training. It is noteworthy, that this is true even though the Kenyans were running at 2000m above sea level.” • VO2max does NOT equal fitness level.

  49. Comparison of Elite Training • Berg • “The dominance of African runners in the last 2 decades may provide valuable insight into the training process. Their training appears to be relatively uncomplicated. In essence, intensity is emphasised over volume.” • “In contrast, in the author’s opinion, training in western countries appears to be guided by a ‘more is better’ philosophy which necessitates limiting intensity.” Berg, K. Endurance Training and Performance in Runners Sports Med 2003; 33 (1): 59-73

  50. Comparison of Training Kenyan Training My Training Now College • BILLAT, V. et al.Training and Bioenergetic Characteristics in Elite Male and Female Kenyan Rusnners. Med. Sci. Sports Exerc., Vol. 35, No. 2, pp. 297-304. 2003.

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