Dr. Paul Nealen
  • Home
  • Research interests
  • Student research colleagues
  • Recent teaching
  • Office hours
  • Science news blog

I often share, and interpret, science news with my students -
some of these reports are collected here.

Does Testosterone Really Give Caster Semenya an Edge on the Track? - The New York Times

5/4/2019

0 Comments

 

Good morning all,

As our term comes to a close, I'll use my last news message to send along the latest news from on ongoing story in exercise physiology that raises interesting, and difficult, questions about sex differences in physiology and the regulation of sporting events.

As we have described in class, both males and females have circulating testosterone, with males generally having much higher levels than females, on average.  But, like all aspects of physiology, there is a wide range of what constitutes "normal" values, and there is overlap between the ranges of naturally-occurring male and female levels.

The science of testosterone is fairly well-understood in terms of its anabolic effects.  Testosterone enables muscle fiber development to a larger size, and facilitates its maintenance at that size.  Testosterone supplements have been used (both knowingly and unknowingly) for decades to help athletes build muscle, and its use was the primary factor which led to the formation of the World Anti-Doping Agency (WADA) and the associated regulations restricting the use of chemicals to enhance the physiology and performance of athletes, especially those competing in sanctioned (e.g., large, high-profile, big money) events. 

Over the last few years in particular, however, we have gained an understanding that much of what makes us male or female is not always so perfectly discrete, so categorical.  For some aspects of our genetics, anatomy, physiology, and performance, male and female traits are most often clearly binary (e.g., one way or the other).  But other of our traits, especially some of our physiology, is not so dimorphic or discrete, and circulating testosterone levels fit into this category.

Males and females generally compete only within same-sex sporting events because, for most events, males hold a competitive advantage.  This is certainly true for track-and field race events, which place emphases on speed and endurance.  This is not to say that female athletes are in any way unimpressive or not elite - they certainly are, and many would leave male competitors 'in the dust'.  But, in general, males outperform females in foot races, and testosterone seems to provide at least some of that advantage, through enhanced muscle size and performance.

Recent analyses have shown that the top female athletes in female track events have testosterone levels higher than the average woman.  This is perhaps not a surprise, as these elite female athletes carry more muscle than the average woman as well.  We must ask - which came first?  Did higher testosterone promote more muscle, which led to racing success?  Or does intense training lead to muscle development and an altered hormonal profile?  Probably some of both.

This situation has reached a peak in recent years over the case of Caster Semenya, an Olympic medalist who hails from South Africa.  By all published accounts, Caster is genetically and physically female, but exhibits hyperandrogenism, a state of producing greater than the normal amount of androgens (male hormones).  She is the most-accomplished middle-distance female athlete of the last decade, to the point at which protests against her have been raised, and regulations put in place to prevent her from racing unless she takes medications to reduce her androgen levels.  She has appealed those decisions, to no avail.

This issue raises many difficult considerations, from the personal (is this athlete being singled-out?  Has her privacy been unfairly invaded?), to the social and political (is this another, familiar case of racism in sport?), to the athletic (is Caster really benefiting from her androgen levels?).  As such, it seems unlikely to be settled easily, or soon.  Nonetheless, it serves as a useful reminder that natural variability is, well, natural - it is an essential part of what allows us to exist as 7 billion different individuals.  There are those among us who are short or tall, thick or thin, slow, - or very fast.  Can we really regulate or legislate ourselves into categories, for competition, or for other reasons?  Most of our physical and physiological traits vary broadly over a continuum, which means that drawing categorical boundaries may be somewhat artificial.  In this case, we seem to have a single physical trait, with a well-understood connection to physical performance, that has become exposed in the very high-profile (and big-money) world of competitive sporting. 

https://www.nytimes.com/2019/05/01/health/caster-semenya-testosterone.html

As we learn more about physiology, we are likely to revisit this issue many times again, and in new ways.  How long will it be before we hear "Is it fair for me to compete against someone who has a better genetic profile than I do?".  I suspect that, in the coming decades, we will be discussing less the physiological and hormonal aspects of physical and mental performance, but rather the genetic bases for them instead.


I'm signing off for the term now.  I hope that these weekly news messages have been useful to you.  This is the first semester that I have used them to this extent, and it has been a learning experience for me.  In particular,
  • I'm surprised how difficult it has been to find good outlets of timely science news that is digestible by the general public. I hope that my go-to sources become regular stops on your tours of Internet science and health news:

    https://www.nytimes.com/section/science
    https://www.nytimes.com/section/health
    https://www.bbc.com/news/science_and_environment
    https://www.bbc.com/news/health
    https://www.sciencedaily.com
    https://www.washingtonpost.com/health
    https://www.sciencenews.org
    https://science.sciencemag.org
    https://www.livescience.com
    https://www.npr.org/sections/science

  • I'm also surprised how a relatively small number of science topics with little direct application to the majority of our population (like space exploration and dinosaurs) occupy such a large portion of the science news.  In some weeks, it was relatively difficult to find recent news related to our lecture topics.

  • I'm impressed by, and proud of, the courageous women (and men) of science who are speaking out in support of the MeToo movement, in an effort to 'level the playing field' and make science more inclusive, equal, and safe for all.  I sat in your seats as an undergraduate more than 30 yrs ago, and saw then how male-dominated science was, and had been.  Since then, it hasn't changed as much as it should have - we still have a long ways to go...

  • I'm discouraged how 'big money' from insurance companies, tobacco companies, and environmental lobbyists influences science and health policy.  Blending money and politics seems inevitably to lead to bad policy, and bad science policy seems inevitably to set us back in our social progress.


In the end, though, I remain very optimistic.  Science is "mankind's organized quest for knowledge" (Floyd Bloom), and we already know that "knowledge is power" (Francis Bacon).  It is science that offers us the best hope to deeper understanding, new therapies and treatments, new cures, and new adventures.  We will encounter many speed-bumps along the way, to be sure.  I hope that our course has inspired you to be a part of this quest, and to make the best use of the knowledge that you gain while on it.

Have a great weekend, and best of luck with all of your exams next week.
Dr. Nealen
0 Comments



Leave a Reply.

    Archives

    February 2020
    January 2020
    December 2019
    November 2019
    October 2019
    September 2019
    August 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    August 2018
    April 2018
    March 2018
    February 2018

    Categories

    All
    Addiction
    Art
    Behavior
    Cancer
    Circulation
    Cognition
    Consciousness
    Conservation
    Coronavirus
    Defenses
    Diet
    Evolution
    Exercise
    Genetics
    Health
    Heredity
    Hormones
    Humans And Their Environment
    Immunity
    Mental Disorders
    Migration
    Neuroscience
    Nobel Prize
    Pain
    Physiology
    Pollution
    Regeneration
    Renal Function
    Reproduction
    Respiration
    Sleep
    Sociality
    Space
    Sport
    Stem Cells
    Temperature
    Vaping
    Vision

    RSS Feed

Proudly powered by Weebly
  • Home
  • Research interests
  • Student research colleagues
  • Recent teaching
  • Office hours
  • Science news blog