Even a low dose of testosterone can give athletes a big performance boost – and in a fraction of the time thought necessary, a study initiated by New Scientist has found. The finding will reinforce calls for drug-testing regimes to be radically stepped up.
The received wisdom is that testosterone must be injected weekly for at least 10 weeks. Yet sports scientist Robert Weatherby of Southern Cross University in Lismore, New South Wales, Australia, who conducted the study, found the biggest increase in performance came after just three weeks.
<figure class="article-image-inline" data-method="caption-shortcode" style="box-sizing: inherit; margin: 0px; padding: 0px; border: 0px; font-size: 16px; font-family: "PT Serif", Georgia, serif; vertical-align: baseline; color: rgb(0, 0, 0);"><figcaption class="font-sans-serif-xxxs--bold" style="box-sizing: inherit; margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; font-size: 0.75rem !important; font-family: "Titillium Web", Helvetica, "Trebuchet MS", Arial, sans-serif !important; line-height: 0.9375rem !important;">Power boost</figcaption>
</figure>Taking testosterone for short periods only, taking smaller doses, or doing both, would reduce the chances of athletes getting caught by drugs testers. “Athletes have probably already figured this out, and we are just confirming that scientifically,” says Randall Urban of the University of Texas at Austin, who has studied the effects of testosterone on older men.
While much attention has focused on synthetic anabolic steroids such as the recently discovered THG, various forms of the natural hormone testosterone are widely abused by athletes and bodybuilders. “Testosterone use is still rampant in sport,” says Christiane Ayotte of the Montreal Doping Control Laboratory in Canada.
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There is also a high level of testosterone abuse in teenagers who want to boost their looks or improve their performance. One survey suggests that an alarming 3.5 per cent of high-school students in the US use steroids like testosterone.
It is fair to assume that at least that proportion is also true for the sporting community, says David Cowan of the Drugs Control Centre at King’s College London. “We may only be catching 10 per cent of those using the drug,” he says.
Muscle size
The first rigorous study of the performance-enhancing effects of testosterone in young men was not carried out until 1996. Volunteers were given weekly injections of either 600 milligrams of testosterone enanthate or a placebo for 10 weeks (bodybuilders usually take much larger doses). Performance tests done at the end of this period showed the hormone had improved muscle size and strength in those doing strength training, and to a lesser extent in those who did not exercise.
The only other comparable study, in 2001, looked at the effects of different doses, but the volunteers were only tested after 20 weeks. No one has ever looked at testosterone’s effects over shorter periods.
In the latest study, Weatherby monitored the performance of 18 male amateur athletes over a six-week training regime. Nine were given weekly shots of testosterone enanthate at a dose of 3.5 milligrams per kilogram of body weight for six weeks (equivalent to roughly half the dose of the 1996 trial), and nine were given a placebo.
The controversial trial, produced by New Scientist, the UK’s Channel 4 and production company Mentorn for a television show broadcast in Australia, Canada, France and the UK this week, was approved by the ethics committee of Southern Cross University.
Less empathic
Weatherby measured the men’s muscle size and performance at the beginning of the trial, and after three and six weeks. Those conducting the tests did not know who was receiving testosterone and who was on the placebo.
The team also looked at the effect of testosterone on the volunteers’ mood, personality and immune system. Unsurprisingly, given the low dose and short duration, no dramatic effects showed up. The personality tests suggest that those on testosterone became less empathic and considerate towards others, and the activity of their immune systems seemed to decline slightly, but there was no significant effect on mood.
There was, however, a dramatic improvement in the performance of the athletes taking testosterone. The most unexpected finding was that the greatest increases in muscle size and power occurred just three weeks into the trial (see graphics).
“I’m surprised it worked that quickly,” says Cowan. Most professional athletes can expect to be tested from once every two years to as frequently as 20 times a year, depending on the level at which they compete. “In the random testing scenario, it could conceivably make it more likely you could slip through without being detected,” he says.
Active and inactive
Testing for testosterone is difficult. With synthetic steroids, all you have to do is prove their presence. But because testosterone is a natural hormone, testers usually have to rely on a few tricks.
The standard method is to measure the ratio of the active and inactive forms of testosterone in an individual’s urine, called the TE ratio. On average, this ratio is 1. When people are taking testosterone, the TE ratio can rise to 10 or more, and after they stop it can fall below 1, because the body stops making testosterone while people are taking big doses. The time it takes for the TE ratio to return to normal once people come off the hormone depends on the size of the doses and how long they were taken for – it can be several months.
Until 2004, the World Anti-Doping Agency, which issues global regulations on drug abuse in sport, only regarded a TE ratio above 6 as suspicious. Last week new regulations came into effect that recommend investigating any abnormal level of testosterone, however low.
The analysis of urine samples from the athletes in the Australian study is not yet complete, but the results of other studies suggest that the TE ratio of people even on this relatively low dose would be high enough for them to be caught out.
However, if athletes or coaches have learned by trial and error to use low doses for short periods only, there is less chance of them being caught. Their TE ratios should also return to normal faster, further reducing the chances of detection even under the new testing regime.
Cowan and Ayotte think a complete overhaul of the testing system is due. “What we really need to do is collect data on individual athletes frequently and over a prolonged period of time to build up testosterone profiles, so that we can explain why they have changes and what their normal levels are,” says Cowan. “We want to catch the cheats, but we also want to get away from pointing the finger at athletes without any proof.”
The received wisdom is that testosterone must be injected weekly for at least 10 weeks. Yet sports scientist Robert Weatherby of Southern Cross University in Lismore, New South Wales, Australia, who conducted the study, found the biggest increase in performance came after just three weeks.
<figure class="article-image-inline" data-method="caption-shortcode" style="box-sizing: inherit; margin: 0px; padding: 0px; border: 0px; font-size: 16px; font-family: "PT Serif", Georgia, serif; vertical-align: baseline; color: rgb(0, 0, 0);"><figcaption class="font-sans-serif-xxxs--bold" style="box-sizing: inherit; margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; font-size: 0.75rem !important; font-family: "Titillium Web", Helvetica, "Trebuchet MS", Arial, sans-serif !important; line-height: 0.9375rem !important;">Power boost</figcaption>
</figure>Taking testosterone for short periods only, taking smaller doses, or doing both, would reduce the chances of athletes getting caught by drugs testers. “Athletes have probably already figured this out, and we are just confirming that scientifically,” says Randall Urban of the University of Texas at Austin, who has studied the effects of testosterone on older men.
While much attention has focused on synthetic anabolic steroids such as the recently discovered THG, various forms of the natural hormone testosterone are widely abused by athletes and bodybuilders. “Testosterone use is still rampant in sport,” says Christiane Ayotte of the Montreal Doping Control Laboratory in Canada.
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There is also a high level of testosterone abuse in teenagers who want to boost their looks or improve their performance. One survey suggests that an alarming 3.5 per cent of high-school students in the US use steroids like testosterone.
It is fair to assume that at least that proportion is also true for the sporting community, says David Cowan of the Drugs Control Centre at King’s College London. “We may only be catching 10 per cent of those using the drug,” he says.
Muscle size
The first rigorous study of the performance-enhancing effects of testosterone in young men was not carried out until 1996. Volunteers were given weekly injections of either 600 milligrams of testosterone enanthate or a placebo for 10 weeks (bodybuilders usually take much larger doses). Performance tests done at the end of this period showed the hormone had improved muscle size and strength in those doing strength training, and to a lesser extent in those who did not exercise.
The only other comparable study, in 2001, looked at the effects of different doses, but the volunteers were only tested after 20 weeks. No one has ever looked at testosterone’s effects over shorter periods.
In the latest study, Weatherby monitored the performance of 18 male amateur athletes over a six-week training regime. Nine were given weekly shots of testosterone enanthate at a dose of 3.5 milligrams per kilogram of body weight for six weeks (equivalent to roughly half the dose of the 1996 trial), and nine were given a placebo.
The controversial trial, produced by New Scientist, the UK’s Channel 4 and production company Mentorn for a television show broadcast in Australia, Canada, France and the UK this week, was approved by the ethics committee of Southern Cross University.
Less empathic
Weatherby measured the men’s muscle size and performance at the beginning of the trial, and after three and six weeks. Those conducting the tests did not know who was receiving testosterone and who was on the placebo.
The team also looked at the effect of testosterone on the volunteers’ mood, personality and immune system. Unsurprisingly, given the low dose and short duration, no dramatic effects showed up. The personality tests suggest that those on testosterone became less empathic and considerate towards others, and the activity of their immune systems seemed to decline slightly, but there was no significant effect on mood.
There was, however, a dramatic improvement in the performance of the athletes taking testosterone. The most unexpected finding was that the greatest increases in muscle size and power occurred just three weeks into the trial (see graphics).
“I’m surprised it worked that quickly,” says Cowan. Most professional athletes can expect to be tested from once every two years to as frequently as 20 times a year, depending on the level at which they compete. “In the random testing scenario, it could conceivably make it more likely you could slip through without being detected,” he says.
Active and inactive
Testing for testosterone is difficult. With synthetic steroids, all you have to do is prove their presence. But because testosterone is a natural hormone, testers usually have to rely on a few tricks.
The standard method is to measure the ratio of the active and inactive forms of testosterone in an individual’s urine, called the TE ratio. On average, this ratio is 1. When people are taking testosterone, the TE ratio can rise to 10 or more, and after they stop it can fall below 1, because the body stops making testosterone while people are taking big doses. The time it takes for the TE ratio to return to normal once people come off the hormone depends on the size of the doses and how long they were taken for – it can be several months.
Until 2004, the World Anti-Doping Agency, which issues global regulations on drug abuse in sport, only regarded a TE ratio above 6 as suspicious. Last week new regulations came into effect that recommend investigating any abnormal level of testosterone, however low.
The analysis of urine samples from the athletes in the Australian study is not yet complete, but the results of other studies suggest that the TE ratio of people even on this relatively low dose would be high enough for them to be caught out.
However, if athletes or coaches have learned by trial and error to use low doses for short periods only, there is less chance of them being caught. Their TE ratios should also return to normal faster, further reducing the chances of detection even under the new testing regime.
Cowan and Ayotte think a complete overhaul of the testing system is due. “What we really need to do is collect data on individual athletes frequently and over a prolonged period of time to build up testosterone profiles, so that we can explain why they have changes and what their normal levels are,” says Cowan. “We want to catch the cheats, but we also want to get away from pointing the finger at athletes without any proof.”
