EXPLAINER: What is human growth hormone — the substance that got Okagbare suspended?

The news of Blessing Okagbare’s immediate suspension from the ongoing Tokyo Olympics came as a shocker to Nigerians, who had expected to watch her represent the country in the women’s 100 meters semi-final heat on Saturday.

Okagbare had, on Friday, finished first in heat 5 in 11.05 (-0.1) seconds, followed by Asha Phillips of the UK at 11.31 seconds.

In a statement, Athletics Integrity Unit (AIU) announced that the 32-year-old Olympic bronze medalist had tested positive for the human growth hormone, a banned substance, in an out-of-competition drug test taken on July 19.

Here is what you should know about the banned substance that Okagabare was suspended for:

WHAT IS HUMAN GROWTH HORMONE?

There are two forms of the human growth hormone, according to the British Journal of Sports Medicine.

There’s the endogenous growth hormone naturally produced by the human body from childhood which dictates the development of the body into adulthood.

On the other hand, there’s the recombinant growth hormone derived from artificially compounded elements, which perform the same function in people, especially children, battling growth deficiency.

The latter has been suspected to be abused by athletes, because of its anabolic properties, which, according to Endocrine Review, “stimulates whole-body protein synthesis, including skeletal muscle and collagen proteins”.

WHY IS IT BANNED IN SPORTS?

The World Anti-Doping Agency (WADA) categorised the growth hormone under its anabolic agents on its prohibited list.

The International Olympic Committee (IOC) first banned the substance in 1989.

It is believed that the growth hormone provides increased muscle mass, power and endurance for athletes, which can give them an advantage over their competitors.

However, the notion that the substance enhances physical performance hasn’t been proven sufficiently.

According to WADA, some of the effects of growth hormone on athletes’ performances include “the reduction of body fat (lipolysis); the increase in muscle mass and strength (anabolic effect), as well as its tissue-repairing effects (recovery) on the musculoskeletal system”.

It can also be used synergistically with other performance-enhancing drugs, which affects muscle anabolism and athletic performance.

POTENTIAL RISKS OF USING THE GROWTH HORMONE?

Continued use of the substance can cause increased blood pressure in the brain, abnormal growth of organs, damage to vision in people with diabetes, swelling or stiffness in the arms and legs, according to the US anti-doping agency.

WADA added that it also reduces the life expectancy of the user significantly.

ATHLETES WHO HAVE BEEN BANNED FOR USING THE SUBSTANCE

Terry Newton, a former British international rugby league player, was the first athlete to be suspended after a positive test for the human growth hormone in 2010.

Mike Junior of the Colorado Rockies, an American baseball team, also tested positive for the substance in 2011.

Okagbare is the biggest name in athletics to test positive for the substance.