The 2012 London Olympics are nearly here. Highlights from the lives of four identical twin Olympic pairs are summarized below. The outcomes of their participation in the games will be fascinating to follow. They raise the questions: How and why are they so successful? Scientific twin research in the world of sports is helpful in explaining why some people become athletes and other do not. It can also tell us why some people turn in elite performances, while other people’s sports performances vary from below average to very good. Research highlights from two scientific overviews of this topic are provided.
Additional information about the Olympic twins can be found in an upcoming issue of Twin Research and Human Genetics (Cambridge University Press). More about twins in general can also be found in my new book Born Together-Reared Apart: The Landmark Minnesota Twin Study and at drnancysegaltwins.org.
• Grant and Ross James. The James twins were recruited for the University of Wisconsin’s rowing team at when a coach spotted the tall lean twins lining up for registration. They went on to win world rowing championships in 2008, 2009 and 2011. The twins said to be “fraternal, but look a lot alike.” I have studied pictures of the twins and believe they are identical. Their coach, who confused them often, is actually a better judge than people who know them well since family and friends have been sensitized to subtle differences between the two.
• Carol and Helen Galashan. Carol and Helen Galashan are synchronized divers from Great Britain. They represented Scotland in the sport of gymnastics, then retired in 2006. The twins became elite divers just two and a half years ago. Their matched physical characteristics may conceivably give them a visual advantage over other competitors.
• Jonathan and Kevin Borlées. Jonathan Borlées is one of Belgium’s fastest runners. He and his identical twin brother, Kevin, and sister Olivia will participate in the London Olympics. The three siblings credit each other for inspiring them to work as hard as possible in athletic competitions.
• Peter and Pavol Hochschomer. The Hochschomer twins will represent Slovakia in the sport of canoeing. The twins won the slalom C-2 event during the last three summer games, and so are favored for the Gold Medal. A fourth victory would be a first.
A 2012 review was prepared by Aldo M. Costa from the Department of Sports Sciences at the University of Beira Interior, in Covithã, Portugal. Costa has reported genetic influence on peak oxygen uptake, although the degree of genetic influence varies across studies. The genetics of the cardiovascular system have also been of interest. The structure, mass and function of heart muscle all show hereditary effects. Lung function also shows genetic influence, but does not seem to affect sports performance. However, repeated short intervals of decreased oxygenation, with or without intense endurance activity, can maintain performance if oxygen levels in the atmosphere are low.
A second 2012 twin research review by Vilhena e Santos from the University of Porto, in Porto, Portugal examined the genetics of physical activity and inactivity. Physical activity concerns body movements produced by skeletal muscles that lead to expenditure of energy. Physical inactivity refers to sedentary behavior that differs from physical activity—in other words, it does not represent the other end of the physical activity spectrum.
Identical-fraternal twin comparisons have shown genetic influence across physical activity, total physical activity, sports participation and leisure time physical activity, with some exceptions. Increasing genetic effects on sports participation were noted for twins entering late adolescence and early adulthood, relative to younger twins. This may reflect individuals’ greater control over their environment as they age and eventually leave home. Younger children living with their families are often required to participate in sports activities they may not enjoy, or may lack opportunities to participate when they want them.
The Olympics is an exciting time. As the games unfold it is likely that other elite twin pairs will surface, possibly leading to unprecedented victories. These twins may also give researchers new ideas about the origins of great athletic performance. The original articles that provided much of this material are listed below.
Costa, A.M., Breitenfeld, L., Silva, A.J., Izquierdo, M., & Marques, M.C. (2012), Genetic inheritance effects on endurance and muscle strength: An update. Sport Medicine, 42, 449-468.
de Vilhena e Santos, D., Katzmaryzk, P.T., Deabra, A.F.T., & Maia, J.A.R. (2012). Genetics of physical activity and physical inactivity in humans. Behavior Genetics, 42, 559-578.
Behavior Genetics, 42, 559-578.
Douglas, S. (27 June, 2012). “2012 London Olympics: Canoeing Preview.” http://www.wdtn.com/dpp/sports/summer_games/2012-london-olympics-canoein...
Hart, S. (2 February, 2009). “Galashan Twins in Sync for London,” 2012,” http://www.telegraph.co.uk/sport/olympics/diving/4436121/Galashan-twins-...
St. Clair, S. (7 July, 2012). “DeKalb Twins in Sync for Olympic Rowing Team,” http://articles.chicagotribune.com/2012-07-07/sports/ct-spt-0708-olympic... (18 July, 2012). “Two Lithe Crew,” Los Angeles Times, p. C6.
Van de Velde, H. (15 March, 20120. London 2012: Borlées Aim to Make 2012 a Family Outing.”