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Can we deter athletes who self-harm to win?
THIS WEEK
The athletes who self-harm to win The Paralympics may encourage a debate on a dangerous practice – and ways to prevent it performance will improve. There is no question that boosting works. In middledistance wheelchair racing, it can shave nearly 10 per cent off race times (Clinical Journal of Sport Medicine, vol 4, p 1). And, although estimates of its prevalence vary, it is not uncommon, says Kirkland, who has never used the technique. But the sweating and shaking associated with boosting also indicates the onset of a medical emergency. Under normal
WHEN Bryan Kirkland sees middle-distance wheelchair racers sweating and shaking on the starting line, he knows it is not necessarily a sign of nerves. Kirkland, a retired member of the US Paralympics team with several medals to his name, says such behaviour is a classic sign of “boosting”, a method of enhancing performance that can mean the difference between defeat and victory. The trouble is, athletes who turn to boosting also tread a line between life and death. Now one spinal cord researcher is calling for a change in rules to stamp out the practice which, while banned by the International Paralympic Committee (IPC), remains difficult to test for. In the vast and inventive world of doping, boosting is unique. People with a spinal injury at the T5 vertebra or higher – around the level of the shoulder blades – typically lose brain control of their cardiovascular system as well as their limbs. Without communication between the brainstem and the cardiovascular system, their bodies do not respond to exercise: heart rate, blood pressure and oxygen uptake do not rise during workouts. Their athletic performance suffers. Boosting allows athletes to overcoming this disadvantage. By intentionally breaking a toe, sitting on their scrotum, or blocking their catheter, a paralysed athlete can kick-start their body’s reaction to stress. Although the athlete will not feel the pain, blood pressure and heart rate will still rise. Their 10 | NewScientist | 1 September 2012
Dylan Martinez/Reuters
Max McClure
circumstances, the rise in blood fatal (Paraplegia, doi.org/fksc3p). pressure following a painful Kirkland’s one unintentional experience is regulated by the experience of AD came after his moderating influence of the catheter was blocked following brainstem. With a spinal injury surgery. “I immediately started at the T5 vertebra or higher, the sweating, my head pounding,” brainstem’s inhibitory signals he says. “I felt like my eyes were cannot get through. going to pop out of my head.” “Once you cut the spinal cord, That the response he felt was so the nerves below the injury will rapid is another consequence of do whatever they want,” says his spinal cord injury. Although Andrei Krassioukov, a spinal many neurons below the injury cord researcher at the University site wither and die because they of British Columbia in Vancouver, no longer receive stimulation Canada. “I started sweating, my Freed from inhibition, the head pounding. I felt like sympathetic nervous system, my eyes were going to which is responsible for ramping pop out of my head.” up the response to stress, keeps goading the body into a more and more excited state. Medics from the brain, those that make have a name for this condition: up pain-detecting circuits autonomic dysreflexia. Without prosper, biologically speaking, prompt treatment, AD can trigger because their activity is normally a stroke or heart attack. In kept in check by the brain. extreme cases, AD has proved Even the body’s attempts to
week, will feature what the IPC’s medical and science director Peter Van de Vliet calls “a combination of random and targeted bloodpressure tests” before events. But Krassioukov, who is studying Paralympians in London during the games, feels that a more drastic change is needed. Both he and Kirkland say that, as things stand, wheelchair sports pit athletes with spinal cord injuries and damaged cardiovascular function against athletes with amputations but fully functioning cardiovascular systems. Changing Paralympic impairment classifications to avoid such a mismatch may not end the practice of boosting altogether, but it might reduce its prevalence if those with spinal cord injuries feel that they are competing on a level playing field. As part of this re-categorisation effort, Krassioukov proposes “cardiovascular health passports”, which would be carried by all athletes with spinal injuries. “These passports would contain a detailed profile of baseline blood pressure, heart rate and other cardiovascular measurements,” he says. Obvious differences between that profile and a profile taken after competition might help identify boosting. Applying such schemes would be complicated, though. Classification is already a knotty, time-consuming feature of sports like wheelchair rugby, where each player receives a number based on an in-depth physical evaluation. The IPC has shied away from considering cardiovascular features in its classification. There is just too much variation from case to case, says Van de Vliet. “Classification is an incredibly difficult puzzle. It simply isn’t practical,” he says. Until that changes, some athletes will continue to use boosting to raise their prospects of winning – much to Kirkland’s bemusement. As he puts it: “You’re risking your life to win –Every edge pursued– a damn race.” n
Aaron Robotham/Simon Driver/Morag Scrimgeour
repair the spinal injury can contribute to AD. When nerves are damaged, they release nerve growth factor – a chemical crucial for nerve repair and survival. However, NGF causes new nerves to sprout, and when it is released in large amounts in the spinal cord, there is a dramatic growth in a section of nerves responsible for relaying sensory signals such as touch. These new nerve fibres amplify the body’s cardiovascular response to a broken toe or similar stimulus. According to Krassioukov, all of these positive feedback loops mean that the only way to treat AD and avoid its potentially lethal consequences is to quickly address whatever stimulus caused the blood pressure to spike. For obvious reasons, then, the IPC has banned boosting on health grounds. The London Paralympics, which began this
–Scanning the universe–
Giant fractals are out – the universe is a big smoothie FRACTALS are beautiful, but we wouldn’t want to live in one. If the universe is like a giant fractal – with matter always appearing in clusters nested inside clusters – that would be a serious blow to modern cosmology. Now the largest 3D map of the sky ever used to measure large-scale structure shows that if you zoom out far enough, the universe is reassuringly cluster-free. We can see that the universe was born smooth by looking at its density, as revealed by the cosmic microwave background radiation, light emitted 380,000 years after the big bang. Over time, gravity pulled matter together so that gas formed stars, those stars gathered in galaxies, and galaxies congregated in clusters. On a large scale, though, the expansion of the universe should trump the influence of gravity and matter should be distributed evenly, according to the standard model of cosmology. But previous studies found clusters within clusters on ever larger scales. One paper even hinted that hyperclusters of galaxies exist out to the 3-billion-light-year scale. To probe the issue, Morag Scrimgeour at the University of Western Australia in Perth and colleagues analysed data from the WiggleZ Dark Energy Survey, which used observations by the AngloAustralian Telescope in New South Wales to map about 220,000 galaxies (the yellow dots, plotted by distance
from Earth, above) in a volume of space equivalent to a cube with 3 billion light years to a side. They tested for clusters by placing any given galaxy in the centre of an imaginary sphere and counting the number of galaxies within it. If clustering exists, there should be more galaxies within a sphere than if the 220,000 galaxies were distributed randomly through the space surveyed. With relatively small spheres, up to about 330 million light years wide (roughly the size of the small square on the left of the picture) they did find galactic clusters. But in larger spheres the number of galaxies met expectations for randomness (arxiv. org/abs/1205.6812). “This is the first survey large enough to… clearly see the approach to homogeneity and then well past it,” says team member Tamara Davis of the University of Queensland in Brisbane. Although few people believe in the idea of a fractal universe, it is very hard to disprove, says Filipe Abdalla of University College London, who was not involved in the study. “This is the nicest result I’ve seen,” he says, but he adds that the results may yet be contradicted by an even larger survey. Scrimgeour admits her team’s work does not rule out clustering at truly epic scales, but she thinks such structures, if they exist, won’t be dense enough to cause problems for cosmology. Michael Slezak n 1 September 2012 | NewScientist | 11
The athletes who self-harm to win The Paralympics may encourage a debate on a dangerous practice – and ways to prevent it performance will improve. There is no question that boosting works. In middledistance wheelchair racing, it can shave nearly 10 per cent off race times (Clinical Journal of Sport Medicine, vol 4, p 1). And, although estimates of its prevalence vary, it is not uncommon, says Kirkland, who has never used the technique. But the sweating and shaking associated with boosting also indicates the onset of a medical emergency. Under normal
WHEN Bryan Kirkland sees middle-distance wheelchair racers sweating and shaking on the starting line, he knows it is not necessarily a sign of nerves. Kirkland, a retired member of the US Paralympics team with several medals to his name, says such behaviour is a classic sign of “boosting”, a method of enhancing performance that can mean the difference between defeat and victory. The trouble is, athletes who turn to boosting also tread a line between life and death. Now one spinal cord researcher is calling for a change in rules to stamp out the practice which, while banned by the International Paralympic Committee (IPC), remains difficult to test for. In the vast and inventive world of doping, boosting is unique. People with a spinal injury at the T5 vertebra or higher – around the level of the shoulder blades – typically lose brain control of their cardiovascular system as well as their limbs. Without communication between the brainstem and the cardiovascular system, their bodies do not respond to exercise: heart rate, blood pressure and oxygen uptake do not rise during workouts. Their athletic performance suffers. Boosting allows athletes to overcoming this disadvantage. By intentionally breaking a toe, sitting on their scrotum, or blocking their catheter, a paralysed athlete can kick-start their body’s reaction to stress. Although the athlete will not feel the pain, blood pressure and heart rate will still rise. Their 10 | NewScientist | 1 September 2012
Dylan Martinez/Reuters
Max McClure
circumstances, the rise in blood fatal (Paraplegia, doi.org/fksc3p). pressure following a painful Kirkland’s one unintentional experience is regulated by the experience of AD came after his moderating influence of the catheter was blocked following brainstem. With a spinal injury surgery. “I immediately started at the T5 vertebra or higher, the sweating, my head pounding,” brainstem’s inhibitory signals he says. “I felt like my eyes were cannot get through. going to pop out of my head.” “Once you cut the spinal cord, That the response he felt was so the nerves below the injury will rapid is another consequence of do whatever they want,” says his spinal cord injury. Although Andrei Krassioukov, a spinal many neurons below the injury cord researcher at the University site wither and die because they of British Columbia in Vancouver, no longer receive stimulation Canada. “I started sweating, my Freed from inhibition, the head pounding. I felt like sympathetic nervous system, my eyes were going to which is responsible for ramping pop out of my head.” up the response to stress, keeps goading the body into a more and more excited state. Medics from the brain, those that make have a name for this condition: up pain-detecting circuits autonomic dysreflexia. Without prosper, biologically speaking, prompt treatment, AD can trigger because their activity is normally a stroke or heart attack. In kept in check by the brain. extreme cases, AD has proved Even the body’s attempts to
week, will feature what the IPC’s medical and science director Peter Van de Vliet calls “a combination of random and targeted bloodpressure tests” before events. But Krassioukov, who is studying Paralympians in London during the games, feels that a more drastic change is needed. Both he and Kirkland say that, as things stand, wheelchair sports pit athletes with spinal cord injuries and damaged cardiovascular function against athletes with amputations but fully functioning cardiovascular systems. Changing Paralympic impairment classifications to avoid such a mismatch may not end the practice of boosting altogether, but it might reduce its prevalence if those with spinal cord injuries feel that they are competing on a level playing field. As part of this re-categorisation effort, Krassioukov proposes “cardiovascular health passports”, which would be carried by all athletes with spinal injuries. “These passports would contain a detailed profile of baseline blood pressure, heart rate and other cardiovascular measurements,” he says. Obvious differences between that profile and a profile taken after competition might help identify boosting. Applying such schemes would be complicated, though. Classification is already a knotty, time-consuming feature of sports like wheelchair rugby, where each player receives a number based on an in-depth physical evaluation. The IPC has shied away from considering cardiovascular features in its classification. There is just too much variation from case to case, says Van de Vliet. “Classification is an incredibly difficult puzzle. It simply isn’t practical,” he says. Until that changes, some athletes will continue to use boosting to raise their prospects of winning – much to Kirkland’s bemusement. As he puts it: “You’re risking your life to win –Every edge pursued– a damn race.” n
Aaron Robotham/Simon Driver/Morag Scrimgeour
repair the spinal injury can contribute to AD. When nerves are damaged, they release nerve growth factor – a chemical crucial for nerve repair and survival. However, NGF causes new nerves to sprout, and when it is released in large amounts in the spinal cord, there is a dramatic growth in a section of nerves responsible for relaying sensory signals such as touch. These new nerve fibres amplify the body’s cardiovascular response to a broken toe or similar stimulus. According to Krassioukov, all of these positive feedback loops mean that the only way to treat AD and avoid its potentially lethal consequences is to quickly address whatever stimulus caused the blood pressure to spike. For obvious reasons, then, the IPC has banned boosting on health grounds. The London Paralympics, which began this
–Scanning the universe–
Giant fractals are out – the universe is a big smoothie FRACTALS are beautiful, but we wouldn’t want to live in one. If the universe is like a giant fractal – with matter always appearing in clusters nested inside clusters – that would be a serious blow to modern cosmology. Now the largest 3D map of the sky ever used to measure large-scale structure shows that if you zoom out far enough, the universe is reassuringly cluster-free. We can see that the universe was born smooth by looking at its density, as revealed by the cosmic microwave background radiation, light emitted 380,000 years after the big bang. Over time, gravity pulled matter together so that gas formed stars, those stars gathered in galaxies, and galaxies congregated in clusters. On a large scale, though, the expansion of the universe should trump the influence of gravity and matter should be distributed evenly, according to the standard model of cosmology. But previous studies found clusters within clusters on ever larger scales. One paper even hinted that hyperclusters of galaxies exist out to the 3-billion-light-year scale. To probe the issue, Morag Scrimgeour at the University of Western Australia in Perth and colleagues analysed data from the WiggleZ Dark Energy Survey, which used observations by the AngloAustralian Telescope in New South Wales to map about 220,000 galaxies (the yellow dots, plotted by distance
from Earth, above) in a volume of space equivalent to a cube with 3 billion light years to a side. They tested for clusters by placing any given galaxy in the centre of an imaginary sphere and counting the number of galaxies within it. If clustering exists, there should be more galaxies within a sphere than if the 220,000 galaxies were distributed randomly through the space surveyed. With relatively small spheres, up to about 330 million light years wide (roughly the size of the small square on the left of the picture) they did find galactic clusters. But in larger spheres the number of galaxies met expectations for randomness (arxiv. org/abs/1205.6812). “This is the first survey large enough to… clearly see the approach to homogeneity and then well past it,” says team member Tamara Davis of the University of Queensland in Brisbane. Although few people believe in the idea of a fractal universe, it is very hard to disprove, says Filipe Abdalla of University College London, who was not involved in the study. “This is the nicest result I’ve seen,” he says, but he adds that the results may yet be contradicted by an even larger survey. Scrimgeour admits her team’s work does not rule out clustering at truly epic scales, but she thinks such structures, if they exist, won’t be dense enough to cause problems for cosmology. Michael Slezak n 1 September 2012 | NewScientist | 11