The line-up of athletes along a start line will vary in a multitude of ways, including height, weight, age, and proportion. This variation is part of sporting culture -- but this hasn't always been the case when it comes to the hormone testosterone.
The line-up of athletes along a start line will vary in a multitude of ways, including height, weight, age, and proportion. This variation is part of sporting culture -- but this hasn't always been the case when it comes to the hormone testosterone.
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Women with naturally high levels of testosterone (hyperandrogenism) were not allowed to compete in the Olympic Games between 2011 and 2015, until Indian 100m runner Dutee Chand challenged IAAF regulations. Here, Chand poses with her winning medal after victory in the 100 meter race during the Federation Cup National Athletics Championship in New Delhi in 2016.
Women with naturally high levels of testosterone (hyperandrogenism) were not allowed to compete in the Olympic Games between 2011 and 2015, until Indian 100m runner Dutee Chand challenged IAAF regulations. Here, Chand poses with her winning medal after victory in the 100 meter race during the Federation Cup National Athletics Championship in New Delhi in 2016.
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The Court of Arbitration for Sport ruled in Chand's favor, arguing that the IAAF had not proven that testosterone gives athletes an unfair advantage. The IAAF was given two more years to find evidence. Here, Chand (right) competes in the Women's 60 meters heats during the 2016 IAAF World Indoor Championships in Portland, Oregon.
The Court of Arbitration for Sport ruled in Chand's favor, arguing that the IAAF had not proven that testosterone gives athletes an unfair advantage. The IAAF was given two more years to find evidence. Here, Chand (right) competes in the Women's 60 meters heats during the 2016 IAAF World Indoor Championships in Portland, Oregon.
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The decision also meant that South African runner Caster Semenya (pictured) -- a fellow athlete with naturally high levels of testosterone -- was able to compete without being forced to take testosterone suppressing drugs. Here, Semenya celebrates winning the gold medal in the women's 800 meters Final during the World Athletics Championships in 2009.
The decision also meant that South African runner Caster Semenya (pictured) -- a fellow athlete with naturally high levels of testosterone -- was able to compete without being forced to take testosterone suppressing drugs. Here, Semenya celebrates winning the gold medal in the women's 800 meters Final during the World Athletics Championships in 2009.
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In 2009, when Semenya was 18, she won gold in the women's 800m at the 2009 World Athletics Championship in Berlin. Her victory was marred by widespread scrutiny of her gender, with the IAAF launching an investigation hours after the race finished. Her gender and testosterone levels were tested and although she was allowed to keep her gold medal, the IAAF ultimately enforced the Hyperandrogenism Regulation in 2011.
In 2009, when Semenya was 18, she won gold in the women's 800m at the 2009 World Athletics Championship in Berlin. Her victory was marred by widespread scrutiny of her gender, with the IAAF launching an investigation hours after the race finished. Her gender and testosterone levels were tested and although she was allowed to keep her gold medal, the IAAF ultimately enforced the Hyperandrogenism Regulation in 2011.
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<a href="index.php?page=&url=http%3A%2F%2Fedition.cnn.com%2F2010%2FSPORT%2F08%2F25%2Fathletics.semenya.commonwealth.games%2F">Some athletes, including Canadian Diane Cummins, </a>have compared racing against Semenya to "running against a man."
Some athletes, including Canadian Diane Cummins, have compared racing against Semenya to "running against a man."
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Pictured, far right, is Ewa Klobukowska of Poland, during the women's 100m final at the 1964 Tokyo Olympics. <a href="index.php?page=&url=https%3A%2F%2Ftheolympians.co%2F2016%2F05%2F19%2Fewa-klubokowskas-timing-was-right-in-1964-but-wrong-in-1967-the-inexact-science-of-gender-testing-in-the-1960s%2F" target="_blank" target="_blank">Klobukowska</a> helped set a world record in the women's 4x100m relay. However, her record was discounted in 1967 after the IAAF found her to have "one chromosome too many" -- an extra Y chromosome, in addition to the traditional XX female chromosomes -- during a gender test.
Pictured, far right, is Ewa Klobukowska of Poland, during the women's 100m final at the 1964 Tokyo Olympics. Klobukowska helped set a world record in the women's 4x100m relay. However, her record was discounted in 1967 after the IAAF found her to have "one chromosome too many" -- an extra Y chromosome, in addition to the traditional XX female chromosomes -- during a gender test.
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