PEAK PERFORMANCE: Olympic athletes competing in London this summer earned their place through countless hours of training and single-minded commitment to their sport. Yet their genetic makeup may be the greatest contributor to their success.
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Take a close look at the athletes competing in this year's Summer Olympic Games in London—their musculature will tell you a lot about how they achieved their elite status. Endless hours of training and commitment to their sport played a big role in building the bodies that got them to the world's premier athletic competition. Take an even closer look—this one requires microscopy—and you'll see something else, something embedded in the genetic blueprints of these young men and women that's just as important to their success.
In nearly all cases, these athletes have realized the full potential laid out by those genes. And that potential may be much greater to begin with than it was for the rest of us mortals. For instance, the genes in the cells that make up sprinter Tyson Gay's legs were encoded with special instructions to build up lots of fast-fiber muscles, giving his legs explosive power out of the starting blocks. In comparison, the maximum contraction velocity of marathoner Shalane Flanagan's leg muscles, as dictated by her genes, is much slower than Gay's yet optimized for the endurance required to run for hours at a time with little tiring. Such genetic fine-tuning also helps competitors in basketball, volleyball and synchronized swimming, although the impact might be much less because effective teamwork and officiating also influence success in those sports.
When the gun goes off for the 100-meter sprint, when swimmers Michael Phelps and Ian Thorpe hit the water, when Tom Daley leaps from his diving platform, we will be seeing the finest that the world's gene pool has to offer, even though scientists are still trying to figure out which genes those are. Unfortunately, history dictates that we may also see the finest in gene manipulation, as some athletes push for peak performance with the help of illegal substances that are becoming increasingly difficult to detect.
The skinny on muscles
The human body produces two types of skeletal muscle fibers—slow-twitch (type 1) and fast-twitch (type 2). The fast-twitch fibers contract many times faster and with more force than the slow-twitch ones do, but they also fatigue more quickly. Each of these muscle types can be further broken down into subcategories, depending on contractile speed, force and fatigue resistance. Type 2B fast-twitch fibers, for example, have a faster contraction time than type 2A.
Muscles can be converted from one subcategory to another but cannot be converted from one type to another. This means that endurance training can give type 2B muscle some of the fatigue-resistant characteristics of type 2A muscle and that weight training can give type 2A muscle some of strength characteristics of type 2B muscle. Endurance training, however, will not convert type 2 muscle to type 1 nor will strength training convert slow-twitch muscle to fast. Endurance athletes have a greater proportion of slow-twitch fibers, whereas sprinters and jumpers have more of the fast-twitch variety.
Just as we can alter our muscle mix only to a certain degree, muscle growth is also carefully regulated in the body. One difference between muscle composition and size, however, is that the latter can more easily be manipulated. Insulinlike growth factor 1 (IGF-1) is both a gene and the protein it expresses that plays an important role during childhood growth and stimulates anabolic effects—such as muscle building—when those children become adults. IGF-1 controls muscle growth with help from the myostatin (MSTN) gene, which produces the myostatin protein.
More than a decade ago H. Lee Sweeney, a molecular physiologist at the University of Pennsylvania, led a team of researchers who used genetic manipulation to create the muscle-bound "Schwarzenegger mice". Mice injected with an extra copy of the IGF-1 gene added muscle and became as much as 30 percent stronger. Sweeney concluded that it is very likely that differences in a person's IGF-1 and MSTN protein levels determine his or her ability to put on muscle when exercising, although he admits this scenario has not been studied widely.
Slow-fiber muscle growth and endurance can likewise be controlled through gene manipulation. In August 2004 a team of researchers that included the Salk Institute for Biological Study's Ronald Evans reported that they altered a gene called PPAR-Delta to enhance its activity in mice, helping nurture fatigue-resistant slow-twitch muscles. These so-called "marathon mice" could run twice as far and for nearly twice as long as their unmodified counterparts.
This demonstrated ability to tinker with either fast- or slow-twitch muscle types begs the question: What would happen if one were to introduce genes for building both fast- and slow-twitch muscle in an athlete? "We've talked about doing it but have never done it," Sweeney says. "I assume you'd end up with a compromise that would be well suited to a sport like cycling, where you need a combination of endurance and power." Still, Sweeney adds, there has been little scientific reason (which translates into funding) to conduct such a study in mice, much less humans.
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18 Comments
Add CommentHas anyone been able to get past the %#@&$%@ oil company's ad to see the second and third parts of the article?
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I was wondering how that female Chinese swimmer clocked a faster time in her freestyle leg of the IM than the world record holder male swimmer.
Reply | Report Abuse | Link to thisAnd she passed her drug test.
Thanks Larry for telling me how she and the Chinese researchers did it!
I figured it was something, but hadn't thought of gene manipulation.
Появление генетически модифицированных людей это начало новой цивилизации и начало конца нашей цивилизации.Они будут умнее,сильнее,красивее,меньше будут болеть но они утратят человеческие качества присущие нам.В дальнейшем они нас будут использовать как гастайбайтеров и генетический материал,отношение к нам будет соответственное.Генетическое модифицирование приведёт к тому,что на генном уровне генетически модифицированное создание нельзя будет идентифицировать на генном уровне как человека.
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Reply | Report Abuse | Link to thisYou can obviously follow this item in English. Why do you react in a language and a script that is not English?
Если бы я знал английский я бы обязательно писал на этом языке.Меня в твиттере читают серёзные имеющие мировое значение организации и они не не жалуются на проблемы с переводом,также как и я на плохой перевод.
Reply | Report Abuse | Link to thisGene therapy or genetic alterations of athletes may be the next step for top athletes. A most likely gene candidate is the Insulinlike growth factor 1 (IGF-1)- yes- perhaps it could replace injections of anabolic steroids? That is a scary thought? So much for screening urine from a cup!!
Reply | Report Abuse | Link to thisIt would be such a blessing if more research took place to figure out how to alter genes to stop certain diseases from taking control of peoples lives. I wonder how one alteration affects other genes though? Is there any research on how additions to one gene affected all of the other genes?
Reply | Report Abuse | Link to thisГенетические изменения спортсменов это первый шаг,второй шаг будет генетические изменения обычных людей и не допущения рождения младенцев с обычными не модифицированными генами.Благими намерениями устлана дорога в ад.Если ген содержит наследственную информацию(мы её получили от Создателя) то от кого получит такую информацию следующее поколение людей?Будут ли они на генном уровне людьми?
Reply | Report Abuse | Link to thisThe research done on the gene IGF-1 and PPAR-delta is somewhat scary stuff. If they could inject mice with this stuff to give them increased muscle mass and fatigue resistance, what's to stop people from doing the same to children. I can envision parents or just trainers so focused on their child or athlete being a success that they are willing to try untested gene therapy on them. Could this research usher in a group of above-human athletes who perform at extremely high levels? I wonder if in the future we will see cases of genetic manipulation with athletes much more regularly.
Reply | Report Abuse | Link to thisIt's interesting that athletes seem to be genetically predisposed to perform well in certain sports, rather than others (beyond the obvious height, build, and bone structure). Looking at this from a cultural (rather than individual perspective)-- Could that be part of the reason that certain nations perform well at certain sports? For example, Jamaica is known for its sprinters and Ethiopia and Kenya for their long distance runners. Perhaps the runners from these nations carry traits that are widely present in their respective cultures, rather than just their families. If this is so, how did these traits originate? What environmental factors over time caused Jaimaicans to exhibit the speed of fast-twitch fibers rather than the endurance of slow-twitch fibers displayed in Kenyan distance runners?
Reply | Report Abuse | Link to thisWatching the London Olympics and seeing how fast people run, swim, and jump almost seems unreal. When I was watching I started to think about how crazy it is to see records people held from 60's and 70's and how much faster people have gotten. It makes me think is it just the training that allows athletes to get better or are they getting some sort of chemical edge? I hope that the testing techniques develop along with the chemicals being created and used.
Reply | Report Abuse | Link to thisIt doesn't surprise me that athletes would try to gene-dope. I find it fascinating how complex the genes are that contribute to muscle composition and development. From a more philosophical/theological view point, I wonder if people are drawn to certain sports because they have the genetic make up for said sport or if people can obtain athletic greatness based soley on training and not genetical advantage. To add the theological side, does God affect the genes of people in such a way as to make them more suitable for certain sports and then adds the desire for said sport in the hearts as they grow up? It is interesting to think that God might do so in order to use a professional athlete to furthur His kingdom through their sporting career.
Reply | Report Abuse | Link to thisWhat an interesting article. Gene therapy is still so new, no one knows the long-term risks involved. Is it worth winning the gold medal if you end up dying 5 years later?
Reply | Report Abuse | Link to thisScience is progressing at a remarkable pace, and Olympic officials may need to increase testing on athletes (require muscle biopsy before competition). Maybe countries should just race genetically improved mice instead? ;)
Reply | Report Abuse | Link to thisOn the opposite end of the scale, this is exciting stuff. IGF-1 stimulates muscle growth and repair; imagine if this is the key to curing muscular dystrophy and other degenerative diseases! Obviously, gene therapy has no place in the athletic world, but the possibilities in the medical field are endless.
I am constantly amazed by the intricacy of the human body, especially at the molecular level. It is fascinating to think that gene therapy could essentially be a useful method in treating certain diseases. However, I worry about the possible side effects of such therapy. Each gene is linked to a web of pathways, which enable the body to function. The insertion of a particular gene could result in the over-production of a specific protein, which could then have a chain reaction on the pathway of that gene. As stated in the article, there could be hundreds of genes that impact muscle growth/function. It seems as though there is much uncertainty about gene therapy and I feel as though much research is necessary before it is utilized. As for the athletic side of things, I amazed at the lengths people will go to succeed. I feel as though one's God given ability and hard work should be enough and I see no glory in achieving victory in any other way. It is amazing that gene therapy could have such positive results, but it is a sad thought that people will use it as a shortcut to success.
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