Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "

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Coming soon in the cycling world: S107

Doping hunters have already developed a test for it and it's being discussed by the WADA experts. So far S107 is only found in labs, but sooner or later the benzothiazepines will appear on the market. The Tour de France will never be the same again.

The diagram below shows the chemical structure of S107, a small molecule. Cardiologists hope to be able to help people with congenital heart problems using S107 and its more complex cousin JTV519, but animal tests show that benzothiazepines are also extremely interesting for the fittest people on the planet: top athletes, ergonauts and other Ergo-log readers.

To explain what benzothiazepines, bear with us as we explain a little science and the role of calcium in muscle contractions.

Muscle fibres contract as calcium from the endoplasmic reticulum [look on it as the cell's industrial zone] flows to the contracting fibres. Calcium works as a catalyst in the fibres, and does its job properly as long as the muscle cells have enough calstabin-1. To be more precise: as long as there's enough calstabin1 attached to the type 1 skeletal muscle ryanodine receptor. This regulates the transportation of calcium through the cell. If the supply of calstabin-1 is exhausted, calcium leaks into the cell and the calcium in the muscle fibres loses its effectiveness. And then muscle cells get tired.

If that happens in the heart muscle because you were born with a defective gene you've got a problem.

S107 and JTV519 force the muscle cells to attach more calstabin1 to the type 1 skeletal muscle ryanodine receptor. That means that less calcium leaks out and the muscles can continue to contract. So it's clear why cardiologists are so interested in benzothiazepines.

And what happens to mice that are given S107 for three weeks continuously and then made to swim every day until they almost drown and run on a treadmill? The mice build up stamina, as the figure below shows.

Coming soon in the cycling world: S107

Continuous extreme physical exercise leads to muscle damage. It leads to an increase in the production of calpain, a catabolic protein, and also in the amount of creatine kinase a muscle damage marker. But these effects are reduced if you give the mice S107. Looks like good stuff for the Tour de F, certainly if you combine it with stimulants like good old caffeine. Caffeine 'stimulates' the ryanodine receptor [ok, we admit that's putting it a bit simply, but still...].

Coming soon in the cycling world: S107

Going on the figures here above the ergogenic effect of S107 is limited. We have written about other nutrients that have had more powerful effects in similar kinds of experiments. But if you read the article [which was written by cardiologists at Columbia University] carefully, you can see why doping hunters are not happy. The researchers also looked at what happens to calstabin-1 and type 1 skeletal muscle ryanodine receptor in human muscle cells if they are subjected to continuous physical effort.

Put more simply, they did tests on cyclists.

The doping researchers at the German Sport University in Cologne read articles like the one written by the Columbia University scientists very carefully. [ 23 January 2009]

Doping hunters are not about to use the tests, says Olivier Rabin of the anti-doping organisation WADA. According to Rabin, the WADA only considers designing a test for a potential doping substance once phase-2 pharmaceutical tests have started. At earlier stages there is still too great a chance that manufacturers will alter the substance. Nevertheless, Rabin does say that the WADA experts have already discussed S107.

Proc Natl Acad Sci U S A. 2008 Feb 12;105(6):2198-202.