Otago knew of his latest problem when they signed him. It was "a more harmless type of offence", said chief executive Ross Dykes, "a mistake rather than a deliberate taking of performance-enhancing drugs."
Sport worldwide needs to rethink its definition of performance-enhancing drugs. It is rightly determined to rid itself of substances that can do athletes harm or give users an artificial and unfair advantage. But dietary supplements such as Ryder used to help him reduce weight are hardly unfair.
The same might be said of potions that enable the body to recover from training more quickly. These no doubt help an athlete follow a more intensive training regime and build more muscular strength, but that is hardly at odds with the values of sport.
Some of the drugs forbidden in competitive sport seem to be perfectly acceptable for personal exercise and commonly used in gymnasiums. It opens the possibility that those who work out independently may become more finely honed specimens than an Olympian who can pass a drug test.
There are some drugs, such as steroids, that organised sport should not permit no matter how much they infiltrate gyms. Anabolic steroids can cause cardiovascular disease, liver damage and other lasting injuries. Nor should sport allow the use of new drugs such as peptides before enough is known about their possible effects.
But for drugs that do no harm - and do somebody of Ryder's build some good - rigorous prohibitions can only do harm to the credibility and enforcement of drug rules in sport.
Enforcement is obviously a problem. For all the concern expressed over many years now, and testing regimes supposedly in force, sport continues to be shamed. Drugs seem to be endemic in some sports, a competitive necessity for serious contenders.
In the fight to dispel that impression, sport cannot afford to be proscribing a pill for weight loss.