From the New York Times:

Study Shows Problems With Olympic-Style Tests

Although athletes have said EPO is in widespread use, few have tested positive. Most of the athletes who have been linked to doping in recent years have been caught not through drug testing, but rather through criminal investigations. In the August 2006 issue of the journal Blood, the American lab accredited to conduct EPO testing reported only 9 positive tests out of 2,600 urine samples.

The new study may help explain why: the test simply failed.

The study, to be published Thursday in the online edition of the Journal of Applied Physiology, was conducted last summer and fall by a renowned lab in Denmark, the Copenhagen Muscle Research Center. The investigators gave eight young men EPO and collected urine samples on multiple occasions before, during and after the men were doping. The men’s urine samples were then sent to two labs accredited by the World Anti-Doping Agency, and EPO tests were requested.

The first lab found some samples positive and a few others suspicious. (A suspicious result does not bring sanctions for doping.) The lab also declared a sample positive, although the man had stopped taking the drug and it should have been gone from his urine. His previous urine sample, obtained when he was taking EPO, was negative in this lab’s test.

The second lab did not deem any urine sample positive for EPO and found only a few to be suspicious. The two labs did not agree on which samples were suspicious.

… [Investigators] realized they had an opportunity to investigate the validity of the EPO test. So, without telling the anti-doping labs what they were doing, the investigators sent the men’s urine samples for EPO testing.

One of the two labs, which the researchers refer to as Lab B in their paper, never declared a sample positive, even when the men were taking high doses of EPO every other day. Lab A was inconsistent. It found EPO during the high dose phase. But in the maintenance phase, it found EPO in only 6 of the 16 samples.

Great news, eh?

Not like “I never tested positive” meant a whole lot before, but with this news, anyone who claims not to have doped and “never testing positive” can have the “yeah, but the tests detect it every time” argument thrown back at them …

And clean athletes will never be able to prove that they haven’t doped … all winning riders are going to fall under suspicion.

“You won the race? You must have doped.”

From The Economist.com:

Sweetness and Light

Low-calorie sweeteners may make people fat

ARTIFICIAL sweeteners have long been touted as being good for the calorie-conscious. Unfortunately, a study just published in Behavioral Neuroscience by Susan Swithers and Terry Davidson of Purdue University in Indiana suggests that such compounds may actually end up making people fatter than they otherwise would be.

Dr Swithers and Dr Davidson came to this conclusion after a series of experiments on rats. In addition to standard laboratory food, they fed some animals yogurt flavoured with saccharin, while others had yogurt flavoured to the same degree of sweetness with normal sugar.

The researchers then carried out two experiments on their animals. One merely tracked the rats’ weight over five weeks. This found that rats eating sweetener gained more weight than those eating sugar. The other experiment was more subtle. After two weeks on yogurt, the rats were given an unexpected treat—a chocolate pudding loaded with calories. Both groups gobbled this up. However, those animals that had been eating sugared yogurt reduced the amount of yogurt they ate for their next meal in proportion to the number of chocolate-flavoured calories they had consumed. Those on the sweetener made no such adjustment.

Dr Swithers and Dr Davidson also measured the body temperatures of their charges before and during the chocolate meal. In normal animals the brain raises the body’s temperature before and during eating. This is to prepare for the energy-intensive job of digestion. As expected, those rats on the sugar diet showed a normal temperature rise. Those on the sweetener, however, showed a diminished increase in temperature, suggesting that their physiology was in some way affected.

The cause, Dr Swithers and Dr Davidson think, is a disruption in the connection that the brain makes between sweetness and calories. Past research suggests that the brain thinks that sweetness is a sign of highly calorific food. Dr Swithers and Dr Davidson argue that artificial sweeteners confuse things. After repeated exposure to sweeteners, the brain forgets the connection and thus fails to stop the animal eating at an appropriate point.

It therefore looks possible that low-calorie artificial sweeteners are a contributory factor to the rising number of people who are obese. What an irony.

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