Do athletes ever fake being fouled by an opposing player in order to invoke a penalty against the opposition? Yes, according to researchers who study human behavior and game theory. Game theory predicts that in any venue, not just sports, dishonest behavior is likely to increase when the potential benefit to the dishonest individual is high and the risk of being caught and punished is low.
Apparently that's what happens in soccer. According to researchers, faked collisions (called “dives”) do not occur randomly over the entire field – they are most common near the goals, where a penalty kick can win or lose a game and where it is more difficult for the referee to judge the fall correctly by virtue of his/her position on the field.
Consistent with game theory, reducing dives in soccer might best be accomplished by ejecting players more often for allegedly taking a dive and by positioning referees closer to the goals.
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Rabu, 02 Februari 2011
Selasa, 21 September 2010
Testing Athletes for Gene Doping
Ever since winning athletic competitions has meant a lot of money, athletes have tried to increase their odds of winning by using performance-enhancing drugs. And for just as long, sports associations have tried to catch the athletes who cheat. In most cases the athletes have stayed one jump ahead by using newer-generation harder-to-detect “designer” drugs as soon as sports associations developed tests to detect the older-generation ones.
Sports associations and many athletes thought that the next level of sophistication in athletic performance enhancement through artificial means (i.e., cheating) was going to be “gene doping” – using genetic engineering techniques to introduce foreign genes into the body that would cause the body to produce performance-enhancing hormones naturally. But the athletes may have lost the detection battle before it even began. Scientists in Germany have already developed a test that they say can conclusively prove with 100% certainty that gene doping has occurred, using a blood sample as small as 200ul. The test looks for the presence of the foreign gene itself, not the protein or hormone product produced by the gene.
It’ll take about two more years for independent laboratories to validate the test, and so it may not be ready by the 2012 Olympics. But even if it’s not, blood samples could be stored and tested later.
Score one for the sports authorities, for once.
Sports associations and many athletes thought that the next level of sophistication in athletic performance enhancement through artificial means (i.e., cheating) was going to be “gene doping” – using genetic engineering techniques to introduce foreign genes into the body that would cause the body to produce performance-enhancing hormones naturally. But the athletes may have lost the detection battle before it even began. Scientists in Germany have already developed a test that they say can conclusively prove with 100% certainty that gene doping has occurred, using a blood sample as small as 200ul. The test looks for the presence of the foreign gene itself, not the protein or hormone product produced by the gene.
It’ll take about two more years for independent laboratories to validate the test, and so it may not be ready by the 2012 Olympics. But even if it’s not, blood samples could be stored and tested later.
Score one for the sports authorities, for once.
Selasa, 07 September 2010
Pre-run Streching Doesn't Prevent Injuries
I reported last year on this blog that the U.S.A. Track & Field association (USATF) was recruiting runners for a study to try to determine whether pre-run stretching prevents running injuries. Coaches and trainers often recommend stretching before exercise, but whether it’s helpful, harmful, or neutral has remained essentially an untested hypothesis.
To test the hypothesis that pre-run stretching reduces the incidence of injuries to runners, the USATF recruited 2,729 runners, defined as persons who ran over 10 miles a week. Each runner was randomly assigned to either a “stretch” or a “no-stretch” group. “No-stretch” runners were instructed not to stretch before running even if they had been in the habit of doing so before. “Stretch” runners were instructed to follow a specific stretch routine before running. All runners were instructed to continue their normal running routine for three months and to report any injuries that caused them to stop running for at least three days.
The results of the study were released last month. Just over half of the runners complied with their assigned group protocol and successfully completed the three months of the study. The results - injury rates were precisely 16% in both groups. In other words, pre-run stretching had no effect on injury rates.
One intriguing finding was that runners who normally stretched before running but were assigned to the “no-stretch” group had a higher injury rate than those who normally didn’t stretch and were in the same group. One hypothesis is that just changing their routine (stopping stretching) may have been enough to predispose them to injury.
So if you’ve always stretched before you run and like doing it, by all means keep doing it. But if you haven’t been in the habit of stretching before running, don’t feel that you have to start.
To test the hypothesis that pre-run stretching reduces the incidence of injuries to runners, the USATF recruited 2,729 runners, defined as persons who ran over 10 miles a week. Each runner was randomly assigned to either a “stretch” or a “no-stretch” group. “No-stretch” runners were instructed not to stretch before running even if they had been in the habit of doing so before. “Stretch” runners were instructed to follow a specific stretch routine before running. All runners were instructed to continue their normal running routine for three months and to report any injuries that caused them to stop running for at least three days.
The results of the study were released last month. Just over half of the runners complied with their assigned group protocol and successfully completed the three months of the study. The results - injury rates were precisely 16% in both groups. In other words, pre-run stretching had no effect on injury rates.
One intriguing finding was that runners who normally stretched before running but were assigned to the “no-stretch” group had a higher injury rate than those who normally didn’t stretch and were in the same group. One hypothesis is that just changing their routine (stopping stretching) may have been enough to predispose them to injury.
So if you’ve always stretched before you run and like doing it, by all means keep doing it. But if you haven’t been in the habit of stretching before running, don’t feel that you have to start.
Sabtu, 14 Agustus 2010
Maximum Heart Rate for Women
Many serious exercisers pay close attention to their heart rates while exercising. That’s because they generally are advised to keep their heart rates within 65-85% of their maximum heart rate for a safe but relatively strenuous workout designed to improve aerobic capacity and endurance.
According to a formula for maximum heart rate that is now 40 years old (it was developed in the 17970s), your maximum heart rate should be around 220 beats per minute (bpm) minus your age. The formula is a population average, of course, and shouldn’t be taken as an absolute number for each individual. More importantly, the old formula was based solely on men subjects. Now a new study of over 5,000 healthy women indicates that a better population-based formula for women is:
Maximum Heart Rate for Women = 206 – (0.88 x age)
Admittedly the new formula has the disadvantage that it can’t be calculated in your head, but it’s easy enough to do with a calculator. And the difference may be significant: By the old formula, a 40-year-old’s 65-85% target range would have been 117-153 bpm. By the new formula, the target range for a 40-yr-old woman would be 111-145 bpm. Six to eight beats per minute might not sound like much, but over an hour’s workout it could make the difference between pushing yourself too far and getting discouraged, and just getting a good healthy workout.
The new study focused only on women subjects. Perhaps someone ought to confirm or revise the old formula for men, too!
Reference: Gulati, M. et al., Heart Rate Response to Exercise Stress Testing in Asymptomatic Women: The St. James Women Take Heart Project. Circulation 122:130-137, 2010.
According to a formula for maximum heart rate that is now 40 years old (it was developed in the 17970s), your maximum heart rate should be around 220 beats per minute (bpm) minus your age. The formula is a population average, of course, and shouldn’t be taken as an absolute number for each individual. More importantly, the old formula was based solely on men subjects. Now a new study of over 5,000 healthy women indicates that a better population-based formula for women is:
Maximum Heart Rate for Women = 206 – (0.88 x age)
Admittedly the new formula has the disadvantage that it can’t be calculated in your head, but it’s easy enough to do with a calculator. And the difference may be significant: By the old formula, a 40-year-old’s 65-85% target range would have been 117-153 bpm. By the new formula, the target range for a 40-yr-old woman would be 111-145 bpm. Six to eight beats per minute might not sound like much, but over an hour’s workout it could make the difference between pushing yourself too far and getting discouraged, and just getting a good healthy workout.
The new study focused only on women subjects. Perhaps someone ought to confirm or revise the old formula for men, too!
Reference: Gulati, M. et al., Heart Rate Response to Exercise Stress Testing in Asymptomatic Women: The St. James Women Take Heart Project. Circulation 122:130-137, 2010.
Jumat, 18 Juni 2010
Reducing the Duration of Muscle Cramps
The cause of muscle cramps during extreme exercise is somewhat of a mystery. The usual explanation is that dehydration-induced electrolyte imbalance leads to inappropriate firing of the motor neurons to the muscle. The usual treatment is physical stretching until the cramping stops, followed by rehydration with salts and water to restore fluid and electrolyte balance.
Is there anything that can shorten the duration of a cramp? Apparently there is – pickle juice! A recent study shows that the duration of cramps deliberately induced in a muscle in the big toe is reduced 37% by drinking about 2 ½ tablespoons of pickle juice as soon as the cramp starts. (Cramps were induced in a muscle in the big toe, because deliberately inducing muscle cramps in a larger muscle was thought to be too painful.)
Interestingly, the pickle juice worked within 1 ½ minutes – too fast to be due to replenishment of body fluids or salts. Researchers speculate that the acetic acid in pickle juice triggers a neural reflex originating in the esophagus or stomach, which somehow inhibits the excessive firing rate of motor neurons to the cramping muscle.
Whether pickle juice will reduce the duration of cramps in major muscle groups in athletes remains to be seen.
Is there anything that can shorten the duration of a cramp? Apparently there is – pickle juice! A recent study shows that the duration of cramps deliberately induced in a muscle in the big toe is reduced 37% by drinking about 2 ½ tablespoons of pickle juice as soon as the cramp starts. (Cramps were induced in a muscle in the big toe, because deliberately inducing muscle cramps in a larger muscle was thought to be too painful.)
Interestingly, the pickle juice worked within 1 ½ minutes – too fast to be due to replenishment of body fluids or salts. Researchers speculate that the acetic acid in pickle juice triggers a neural reflex originating in the esophagus or stomach, which somehow inhibits the excessive firing rate of motor neurons to the cramping muscle.
Whether pickle juice will reduce the duration of cramps in major muscle groups in athletes remains to be seen.
Kamis, 03 Juni 2010
Beating the EPO Blood Doping Test
Synthetic erythropoietin, called EPO, was widely used by endurance athletes in the 1990s to boost red blood cell production and blood oxygen carrying capacity. The use of EPO declined after 2000 when the World Anti-Doping Agency (WADA) developed a test to detect EPO in urine.
But now, WADA believes that athletes could be beating the current EPO urine tests by “microdosing” – injecting very small (micro) doses of EPO at night. EPO is excreted so rapidly into the urine that most of an injected dose will be eliminated from the body within eight hours. Thus, microdosing is likely to go undetected as long as urine samples are not demanded in the middle of the night.
Microdosing works because the effects of the erythropoietin outlast the hormone itself. Researchers now know that even such small, intermittent doses of EPO will boost the body’s production of red blood cells significantly over time. They aren’t publishing their dosage information to avoid providing a recipe for blood-doping, but they suspect that athletes already know.
But now, WADA believes that athletes could be beating the current EPO urine tests by “microdosing” – injecting very small (micro) doses of EPO at night. EPO is excreted so rapidly into the urine that most of an injected dose will be eliminated from the body within eight hours. Thus, microdosing is likely to go undetected as long as urine samples are not demanded in the middle of the night.
Microdosing works because the effects of the erythropoietin outlast the hormone itself. Researchers now know that even such small, intermittent doses of EPO will boost the body’s production of red blood cells significantly over time. They aren’t publishing their dosage information to avoid providing a recipe for blood-doping, but they suspect that athletes already know.
Sabtu, 06 Maret 2010
Athlete Caught Doping with Growth Hormone
British rugby player Terry Newton has the distinction of being the first athlete ever caught doping with growth hormone to boost muscle mass. He’s been banned from rugby competition for two years.
Until recently athletes had assumed that human growth hormone doping was undetectable, because the synthetic form of growth hormone looks exactly like natural growth hormone. But then scientists discovered that the body actually produces several different forms of the hormone, and that by examining the ratio of these different forms in blood they could tell if the pure synthetic form had been administered. Anti-doping agencies also began requiring random blood tests rather than just tests after athletic events, because the hormone disappears from the blood just days after administration. It was a random test that caught Mr. Newton.
The U.S. National Football League and Major League Baseball have shown interest in the test but so far it has not been instituted, in part because it requires a blood sample.
Until recently athletes had assumed that human growth hormone doping was undetectable, because the synthetic form of growth hormone looks exactly like natural growth hormone. But then scientists discovered that the body actually produces several different forms of the hormone, and that by examining the ratio of these different forms in blood they could tell if the pure synthetic form had been administered. Anti-doping agencies also began requiring random blood tests rather than just tests after athletic events, because the hormone disappears from the blood just days after administration. It was a random test that caught Mr. Newton.
The U.S. National Football League and Major League Baseball have shown interest in the test but so far it has not been instituted, in part because it requires a blood sample.
Selasa, 09 Februari 2010
Platelet-Rich Plasma Therapy Revisited
About a year ago in this blog I described PRP (platelet-rich plasma) therapy as an exciting and potentially effective new treatment for injuries to tendons and ligaments. Apparently athletes and other patients were asking for the treatment, even though insurance companies were reluctant to pay for it. I asked, “Does it work?” and mentioned that several clinical trials were currently underway to find out.
The results of several of the clinical trials are now in, and the results are not encouraging. In one study of patients with Achilles tendon injuries, PRP therapy was no more effective than an injection of saline (the control). In another study of tennis elbow, PRP therapy appeared to be slightly more effective than injections of steroids (the standard treatment these days). However, some scientists have criticized the tennis elbow study for not having a control group. Steroid injections are known to reduce pain in the short-term but to slow healing in the long-term. So the jury is still out on whether PRP therapy for tennis elbow is actually better than no treatment at all.
No doubt, studies with other tendon/ligament injuries using different study protocols will be done in the future. In the meantime, enthusiasm for PRP therapy has cooled just a little.
The results of several of the clinical trials are now in, and the results are not encouraging. In one study of patients with Achilles tendon injuries, PRP therapy was no more effective than an injection of saline (the control). In another study of tennis elbow, PRP therapy appeared to be slightly more effective than injections of steroids (the standard treatment these days). However, some scientists have criticized the tennis elbow study for not having a control group. Steroid injections are known to reduce pain in the short-term but to slow healing in the long-term. So the jury is still out on whether PRP therapy for tennis elbow is actually better than no treatment at all.
No doubt, studies with other tendon/ligament injuries using different study protocols will be done in the future. In the meantime, enthusiasm for PRP therapy has cooled just a little.
Kamis, 10 September 2009
Treating "pre-osteoporosis"
First the definition of “overweight” was changed, making 35 million more Americans overweight overnight. Then normal blood pressure was redefined, and everyone just above it became “pre-hypertensive”. And now, millions of women with a bone density just slightly below normal (for a 30-year-old!) are being told they have a condition called “pre-osteoporosis”, or “osteopenia”. This is like telling a middle-aged woman she has a skin disease because her skin is not as smooth as her daughter’s. In fact, a woman’s bone density normally declines with age – its just part of the aging process. Bone density declines very slowly after 30 but before menopause, and then accelerates after menopause.
The pharmaceutical industry helped to define osteopenia, and it also has the pills to treat it. Call me a skeptic, but I’m guessing they had an interest in seeing a lot of women diagnosed with the condition. Some doctors are suggesting that the drugs used to treat osteopenia are being over-marketed to younger post-menopausal women who may still be at relatively low risk for bone fractures. They argue that the benefits of the drugs used to treat osteopenia are exaggerated and the risks generally are downplayed. If you're still young, consult your physician before taking drugs to treat osteopenia. Otherwise you could be trying to treat a problem that you don’t really have yet.
REFERENCE: P. Alonso-Coello, et al. Drugs for pre-osteoporosis – prevention or disease-mongering? British Medical Journal 336:126-129, 2008.
The pharmaceutical industry helped to define osteopenia, and it also has the pills to treat it. Call me a skeptic, but I’m guessing they had an interest in seeing a lot of women diagnosed with the condition. Some doctors are suggesting that the drugs used to treat osteopenia are being over-marketed to younger post-menopausal women who may still be at relatively low risk for bone fractures. They argue that the benefits of the drugs used to treat osteopenia are exaggerated and the risks generally are downplayed. If you're still young, consult your physician before taking drugs to treat osteopenia. Otherwise you could be trying to treat a problem that you don’t really have yet.
REFERENCE: P. Alonso-Coello, et al. Drugs for pre-osteoporosis – prevention or disease-mongering? British Medical Journal 336:126-129, 2008.
Selasa, 11 Agustus 2009
Is Running Hard on Knees?
Runners are often told (usually by non-runners) that running is hard on their knees. According to commonly held belief, the constant pounding wears out or damages knee cartilage and leads to either knee injury or an increased likelihood of osteoarthritis later in life.
But the available scientific evidence suggests that running is not a risk factor for knee osteoarthritis, and may in fact keep you healthier later in life. In one study, runners were compared to age-matched non-runners over an 18-year period. There was no difference in the rate of development of osteoarthritis between the two groups. In another study, overall disability rates in runners increased at only one quarter of the rate seen in age-matched sedentary persons.
A major risk factor for knee osteoarthritis is not running per se; its having had a previous knee injury. That is why there is so much osteoarthritis among former N.F.L. football players and former soccer players. But if you’re a recreational runner and manage to stay injury-free, don’t worry about wearing out your knees – just keep running!
But the available scientific evidence suggests that running is not a risk factor for knee osteoarthritis, and may in fact keep you healthier later in life. In one study, runners were compared to age-matched non-runners over an 18-year period. There was no difference in the rate of development of osteoarthritis between the two groups. In another study, overall disability rates in runners increased at only one quarter of the rate seen in age-matched sedentary persons.
A major risk factor for knee osteoarthritis is not running per se; its having had a previous knee injury. That is why there is so much osteoarthritis among former N.F.L. football players and former soccer players. But if you’re a recreational runner and manage to stay injury-free, don’t worry about wearing out your knees – just keep running!
Kamis, 18 Juni 2009
Stretching and Sports Injuries
Does stretching before exercise reduce the risk of sports injuries? Many coaches, trainers, and athletes swear that it does, but no one knows for sure because the critical experiment has never been done.
Now researchers are attempting to do the experiment. Sponsored by USA Track & Field (USATF), the researchers are currently enrolling people who run at least 10 miles per week. Participants must agree to be assigned randomly to either the "stretch" or the "no-stretch" group and to adhere to the study protocol for three months. Runners in both groups are expected to report their injuries during the study period.
Runners can apply to be participants at www.usatf.org/stretchStudy/. So far several thousand runners have signed up, though not all of them have completed the study protocol and submitted their reports. The results will be made public as soon as enough runners have completed the protocol for there to be a statistically significant difference between the groups, or when enough data has accumulated to show that there is no difference. Ultimately, up to 10,000 runners may be needed.
Runners, this is your golden opportunity to contribute to the advancement of science.
Now researchers are attempting to do the experiment. Sponsored by USA Track & Field (USATF), the researchers are currently enrolling people who run at least 10 miles per week. Participants must agree to be assigned randomly to either the "stretch" or the "no-stretch" group and to adhere to the study protocol for three months. Runners in both groups are expected to report their injuries during the study period.
Runners can apply to be participants at www.usatf.org/stretchStudy/. So far several thousand runners have signed up, though not all of them have completed the study protocol and submitted their reports. The results will be made public as soon as enough runners have completed the protocol for there to be a statistically significant difference between the groups, or when enough data has accumulated to show that there is no difference. Ultimately, up to 10,000 runners may be needed.
Runners, this is your golden opportunity to contribute to the advancement of science.
Rabu, 18 Februari 2009
PRP Therapy for Connective Tissue Injuries
If you’ve ever injured a tendon or ligament you know how painful such injuries can be. You also know that injured connective tissue takes longer to heal than injured muscle tissue. That’s because there is generally very little blood flow to connective tissue, especially in areas in and around fluid-filled joints. As a result, very few blood platelets and white blood cells are delivered to the area to help with tissue repair.
Experts in sports medicine now think they have a potential solution. It’s called “platelet-rich plasma therapy”, or PRP for short. The method is surprisingly straightforward. A sample of the patient’s own blood is enriched in platelets by removal of the blood cells and most of the water and electrolytes. The remaining platelet-enriched plasma is then injected directly into the injured joint or connective tissue. The theory is that the platelets will release proteins involved in tissue repair and attract other tissue-repair cells to the area, speeding the healing process.
Does PRP therapy work for such common connective tissue injuries as rotator cuff strains, Achilles tendon injuries, and tennis elbow? Clinical trials are underway in several countries, including the U.S., to find out. Meanwhile, some professional athletes have already tried it, including Los Angeles Dodgers’ baseball pitcher Takashi Saito and Pittsburgh Steelers’ receiver Hines Ward. Ward has his answer already; he was able to play in the Superbowl just two weeks after a knee injury that generally sidelines players for 4-6 weeks.
Experts in sports medicine now think they have a potential solution. It’s called “platelet-rich plasma therapy”, or PRP for short. The method is surprisingly straightforward. A sample of the patient’s own blood is enriched in platelets by removal of the blood cells and most of the water and electrolytes. The remaining platelet-enriched plasma is then injected directly into the injured joint or connective tissue. The theory is that the platelets will release proteins involved in tissue repair and attract other tissue-repair cells to the area, speeding the healing process.
Does PRP therapy work for such common connective tissue injuries as rotator cuff strains, Achilles tendon injuries, and tennis elbow? Clinical trials are underway in several countries, including the U.S., to find out. Meanwhile, some professional athletes have already tried it, including Los Angeles Dodgers’ baseball pitcher Takashi Saito and Pittsburgh Steelers’ receiver Hines Ward. Ward has his answer already; he was able to play in the Superbowl just two weeks after a knee injury that generally sidelines players for 4-6 weeks.
Kamis, 09 Oktober 2008
New Drug Test for Athletes
The International Olympics Committee plans to retest many of the nearly 1,000 blood samples it collected during the 2008 games in Beijing for a synthetic analogue of the natural hormone erythropoietin, called CERA. CERA is a so-called “designer drug” that was supposed to escape detection. But a test is now available to detect CERA, and several Tour de France cyclists subsequently were found to have used it.
According to World Anti-Doping Agency rules, an athlete’s blood may be retested for up to eight years after an athletic event. The International Olympics Committee keeps blood samples for eight years for situations like this, in which a new test is developed to detect a previously undetectable performance-enhancing drug. It’s just another way that sports authorities try to keep up with athletes who are willing to cheat. Sports authorities hope that the knowledge that an athlete might still be stripped of his/her medals up to eight years after a competition will deter some athletes from using drugs in the first place. But the desire to win is strong, and no one knows if the strategy will work.
According to World Anti-Doping Agency rules, an athlete’s blood may be retested for up to eight years after an athletic event. The International Olympics Committee keeps blood samples for eight years for situations like this, in which a new test is developed to detect a previously undetectable performance-enhancing drug. It’s just another way that sports authorities try to keep up with athletes who are willing to cheat. Sports authorities hope that the knowledge that an athlete might still be stripped of his/her medals up to eight years after a competition will deter some athletes from using drugs in the first place. But the desire to win is strong, and no one knows if the strategy will work.
Rabu, 30 April 2008
Beating the Testosterone Doping Test
According to a study by Swedish researchers, a common genetic deficiency might make it possible for some people to beat the standard testosterone doping test, even if they had been doping with the hormone. The researchers injected 55 male volunteers with testosterone and then tested them with the standard urine test for testosterone doping. More than 40% of all subjects with the genetic deficiency tested negative for testosterone doping over a 15-day testing period.
Two-thirds of the Asian population and about 10% of all Caucasians are deficient in the gene in question. The World Anti-Doping Agency is concerned, but it appears that there is little that they can do about it at this time. Genetic tests would reveal which athletes could beat the testosterone doping test, but genetic testing is not part of the standard anti-doping test for Olympic athletes. Individuals with the genetic deficiency may be able to use testosterone and get away with it, at least until the rules change.
Two-thirds of the Asian population and about 10% of all Caucasians are deficient in the gene in question. The World Anti-Doping Agency is concerned, but it appears that there is little that they can do about it at this time. Genetic tests would reveal which athletes could beat the testosterone doping test, but genetic testing is not part of the standard anti-doping test for Olympic athletes. Individuals with the genetic deficiency may be able to use testosterone and get away with it, at least until the rules change.
Senin, 31 Maret 2008
Speedier Speedos
Can a swimsuit make you go faster in the water? Will athletes be willing to pay more than $500 for one? Speedo is betting that the answer to both questions is “yes”. Its new high-tech Speedo LZR Racer is designed to do for swimming what titanium golf clubs and carbon composite rackets did for golf and tennis, respectively. And it might do just that!
The new suit has no stitching; the parts are all bonded ultrasonically. Low-drag panels are incorporated into the nearly complete body suit to compress the swimmer’s body. According to the company, the new suits have 5% less drag than older models. Critics argue that a suit doesn’t make a world-class swimmer, and of course on one level they’re right. On the other hand, in the past two months 14 new world records have been set in swimming – 13 of them in the LZR suit.
Expect to see the new suit all over the Olympics swimming competitions this summer.
The new suit has no stitching; the parts are all bonded ultrasonically. Low-drag panels are incorporated into the nearly complete body suit to compress the swimmer’s body. According to the company, the new suits have 5% less drag than older models. Critics argue that a suit doesn’t make a world-class swimmer, and of course on one level they’re right. On the other hand, in the past two months 14 new world records have been set in swimming – 13 of them in the LZR suit.
Expect to see the new suit all over the Olympics swimming competitions this summer.
Minggu, 16 Maret 2008
A REALLY Costly Drug
A drug called Cerezyme has become a topic of debate among health care professionals, insurance companies, and patients. That’s because at the recommended dosage, the drug costs up to $300,000 per year.
Cerezyme is used to treat a rare inherited disorder called Gaucher disease, characterized by severe deterioration of bones and joints. The recommended dosage was determined on the basis of a clinical trial in only twelve patients more than 15 years ago. At the recommended dosage the drug has proven to be quite effective. But would a lower dose work just as well? Many doctors and insurance companies think so, but the manufacturer (Genzyme) has no interest in finding out. And why would they, when the drug has annual sales of over a billion dollars? Genzyme says it’s not their issue; they’d leave it up to doctors to determine whether a lesser dose would work just as well in their patients.
If the drug were cheap, dosage wouldn’t be an issue. But insurance companies are paying for this drug, and therefore so are we, indirectly. Who do you think should be responsible for determining the proper dose?
Cerezyme is used to treat a rare inherited disorder called Gaucher disease, characterized by severe deterioration of bones and joints. The recommended dosage was determined on the basis of a clinical trial in only twelve patients more than 15 years ago. At the recommended dosage the drug has proven to be quite effective. But would a lower dose work just as well? Many doctors and insurance companies think so, but the manufacturer (Genzyme) has no interest in finding out. And why would they, when the drug has annual sales of over a billion dollars? Genzyme says it’s not their issue; they’d leave it up to doctors to determine whether a lesser dose would work just as well in their patients.
If the drug were cheap, dosage wouldn’t be an issue. But insurance companies are paying for this drug, and therefore so are we, indirectly. Who do you think should be responsible for determining the proper dose?
Jumat, 16 November 2007
Barry Bonds Indicted
Home run king Barry Bonds was indicted this week on felony charges that could send him to prison for at least a decade. Bonds is charged with lying under oath to a federal grand jury back in 2003. Bonds has always claimed that he never knowingly used performance-enhancing steroids, but government investigators now say they can prove that Mr. Bonds used steroids, based on a positive blood test seized during an investigation of a California laboratory that sells them. Bond’s lawyer calls the charges “ridiculous”. The case may drag on in the courts for years. In the meantime, many baseball fans will consider Bonds’ home run record to have an asterisk after it.
The dangers of steroid abuse by athletes are discussed in Human Biology 5th ed., pp. 134-135.
The dangers of steroid abuse by athletes are discussed in Human Biology 5th ed., pp. 134-135.
Kamis, 01 November 2007
The Buzz on Bone and Fat
In Human Physiology 5th ed. (p. 104-105) I point out that bone growth, remodeling and repair are enhanced by weight-bearing exercise and can be stimulated by weak electrical currents. But I learned something new today - apparently it’s also known that that in several animal species including mice and sheep, just standing on a platform that vibrates at a low frequency (like a buzz) leads to bone growth. That’s interesting enough, but now scientist have demonstrated that when mice are placed on a vibrating platform for just 15 minutes a day they not only gain bone mass, they also have 27% less body fat. The work will be published in the Proceedings of the National Academy of Sciences Nov. 6, but it is already available online.
Huh? It sounds incredible - so incredible that it amazes even the scientists who did it. They caution that they don’t yet understand WHY the mice gain bone mass and have less body fat, but they have some hypotheses. One is that the low frequency vibrations may stimulate stem cells in bone to become bone cells instead of fat cells. Other scientists remain skeptical of this hypothesis, saying that perhaps the mice have less fat because they eat less or because they are doing more muscle work to maintain their posture on the platform. Certainly these are all good hypotheses that deserve to be tested.
According to a New York Times article published online on Oct. 30 (“Low Buzz May Give Mice Better Bones and Less Fat”, by Gina Kolata), a clinical trial is underway in elderly people to determine whether a buzzing platform will affect adult human bone density (and body fat) like it does in mice. Perhaps in a few years we’ll know, and a new therapy for osteoporosis will emerge.
Huh? It sounds incredible - so incredible that it amazes even the scientists who did it. They caution that they don’t yet understand WHY the mice gain bone mass and have less body fat, but they have some hypotheses. One is that the low frequency vibrations may stimulate stem cells in bone to become bone cells instead of fat cells. Other scientists remain skeptical of this hypothesis, saying that perhaps the mice have less fat because they eat less or because they are doing more muscle work to maintain their posture on the platform. Certainly these are all good hypotheses that deserve to be tested.
According to a New York Times article published online on Oct. 30 (“Low Buzz May Give Mice Better Bones and Less Fat”, by Gina Kolata), a clinical trial is underway in elderly people to determine whether a buzzing platform will affect adult human bone density (and body fat) like it does in mice. Perhaps in a few years we’ll know, and a new therapy for osteoporosis will emerge.
Kamis, 27 September 2007
Body Size and Athletic Ability
According to an article in the on-line version of The New York Times today (“Bigger is Better, Except When It’s Not”), world-class rowers usually are big. Swimmers are tall. Distance runners are small and light. It’s all according to the rules of physics, exercise researchers say.
Previously I speculated that in a high-tech future world, children and their parents will be able to choose what sports the child is most likely to excel in based on hard scientific evidence (see the Directions in Science feature in Human Biology 5th ed., p. 132). Apparently some of the evidence is now known. But this does not mean that size, body form, and muscle biochemistry are all that matter. As the experience of Lance Armstrong has shown, good training and desire also count for something, too. Unless you aspire to be the best in the world, go out and do what you enjoy!
Previously I speculated that in a high-tech future world, children and their parents will be able to choose what sports the child is most likely to excel in based on hard scientific evidence (see the Directions in Science feature in Human Biology 5th ed., p. 132). Apparently some of the evidence is now known. But this does not mean that size, body form, and muscle biochemistry are all that matter. As the experience of Lance Armstrong has shown, good training and desire also count for something, too. Unless you aspire to be the best in the world, go out and do what you enjoy!
Rabu, 12 September 2007
New Twist on Steroid Use in Baseball
According to a report on CNN’s Sports Illustrated website (SI.com) this week, three major-league baseball players received shipments of banned performance-enhancing (anabolic) steroids over several years. The report cites records obtained from unnamed sources. Although Major League Baseball has asked to talk to the players, none of the three has yet tested positive for steroids.
Huh? Perhaps we’ll hear a variation of the old “I smoked but I didn’t inhale” defense - “I bought them, but I never used them…”.
Anti-doping experts believe that players may be escaping detection by using human growth hormone in conjunction with very small doses of performance-enhancing steroids such as testosterone. Although there is no reliable test for exogenous human growth hormone, its use is banned by Major League Baseball.
The use of anabolic steroids in sports is discussed in Human Biology, 5th ed., pp. 134-135.
Huh? Perhaps we’ll hear a variation of the old “I smoked but I didn’t inhale” defense - “I bought them, but I never used them…”.
Anti-doping experts believe that players may be escaping detection by using human growth hormone in conjunction with very small doses of performance-enhancing steroids such as testosterone. Although there is no reliable test for exogenous human growth hormone, its use is banned by Major League Baseball.
The use of anabolic steroids in sports is discussed in Human Biology, 5th ed., pp. 134-135.
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