Artur Beterbiev vs. Callum Smith: Beterbiev's atypical test explained

The narrative heading into the eagerly anticipated Artur Beterbiev vs. Callum Smith world title fight switched drastically with less than 48 hours until the first bell.

On Thursday it emerged that unified light heavyweight champion Beterbiev turned in an atypical test to VADA on December 6. Samples revealed that the Russian star had "elevated levels" of HGH (Human Growth Hormone) and testosterone. This story was first broken by boxing writer Kevin Iole.

HGH and testosterone are natural hormones that are produced by the body. The reason VADA was compelled to bring these findings to the attention of all involved is because of the levels being above what would ordinarily be expected to occur naturally.

WATCH: Beterbiev vs. Smith, LIVE on ESPN+

The bout is not under threat and Beterbiev has passed additional blood and urine tests that were requested by VADA.

The Sporting News now looks into HGH, testosterone and the difference between an atypical finding and an adverse finding.

What is HGH (Human Growth Hormone)?

Firstly, HGH is not a steroid. It is a natural hormone produced by the pituitary gland.

The reason why it can be flagged up in testing is because it’s illegal for athletes to boost their HGH unnaturally. It can also be used in conjunction with other substances to enhance athletic performance and help with recovery.

There is no evidence whatsoever to suggest that Beterbiev has done this and, as previously stated, testing before and after his atypical finding was clear.

What is Testosterone?

Testosterone is another natural hormone found in human beings and other animals. In men, it is produced mainly by the testicles, while in women it is produced by the ovaries in smaller amounts.

As is the case with HGH, athletes can boost their levels of testosterone. According to the National Library of Medicine: “Elevated testosterone levels have been demonstrated to increase the growth of body muscles and contribute to better activation of the nervous system, resulting in more power and strength.”

Again, there is no evidence to suggest that Beterbiev has experimented with testosterone boosters.

MORE: Artur Beterbiev's top five knockout wins

What is the difference between an atypical finding and an adverse finding?

The atypical result is something of a grey area. It’s not a negative test, it’s not a positive test, it’s somewhere in the middle. This begs the question: why mention these results at all?

Reportedly, atypical results are quite common and such findings rarely reach the public domain because it’s not an adverse test and has no bearing on whether an athlete can compete or not.

An adverse test is when an athlete fails due to the presence of a performance-enhancing drug or its metabolites/ markers within a sample.

“It is difficult to release the information [of an atypical finding] because they will feel that people will accuse Artur,” said Smith’s promoter Eddie Hearn when questioned by a group of reporters.

“Again, it is not an adverse finding, but when those substances are raised levels, we cannot help but investigate further; we would be doing our job.”

“Callum’s lawyer has been doing that with VADA. Again, we would like a little more information, but it will not affect the fight anyway; the fight would only be cancelled if there was an adverse test.”

How to watch Artur Beterbiev vs. Callum Smith: TV channel, live stream

Artur Beterbiev vs. Callum Smith is live on ESPN+ in the U.S.

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Artur Beterbiev vs. Callum Smith price: How much does the fight cost? 

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