The International Association of Athletics Federation (IAAF) has revealed its new eligibility regulations for "female classification" today—these rules could impede on South African middle-distance athlete Caster Semenya's performance.

These regulations are for events from the 400m to the mile, including hurdles, 400m, 800m and 1500m races and will go into effect from November 1.

According to the report, the IAAF requires any athlete who has a "Difference of Sexual Development (DSD)," meaning an athlete who is "androgen-sensitive" with levels of testosterone are 5 nmol/L or above to meet the following criteria to be eligible to compete in "restricted events" in an international competition:

"a) she must be recognized at law either as female or as intersex (or equivalent)
b) she must reduce her blood testosterone level to below 5 nmol/L for a continuous period of at least six months
c) thereafter she must maintain her blood testosterone level below 5 nmol/L continuously for so long as she wished to remain eligible."

"We want athletes to be incentivized to make the huge commitment and sacrifice required to excel in the sport, and to inspire new generations to join the sport and aspire to the same excellence," IAAF President Sebastian Coe says in the announcement.

"As the International Federation for our sport we have a responsibility to ensure a level playing field for athletes. Like many other sports we choose to have two classifications for our competition—men's events and women's events. This means we need to be clear about the competition criteria for these two categories. Our evidence and data show that testosterone, either naturally produced or artificially inserted into the body, provides significant performance advantages in female athletes. The revised rules are not about cheating, no athlete with a DSD has cheated, they are about leveling the playing field to ensure fair and meaningful competition in the sport of athletics where success is determined by talent, dedication and hard work rather than other contributing factors."

Read the report in full here.

Sports scientist Ross Tuckertells the Guardian that this new policy could significantly slow down Semenya's time in the 800m race.

"History suggests Semenya will lose about four seconds to five seconds," Tucker says to the Guardian. "Because in 2013 and 2014, when the IAAF were diligent about ensuring her compliance with the upper limit at that time (10nM), she was running 2:00. I don't think she even qualified for the Commonwealth Games. Now, at 5nM, that effect will be even larger, I suspect. She will go from a 1:54 to 2:01-2:03, is my estimate."

Although opinions on these regulations in relation to Semenya vary, many South Africans and observers of the IAAF on Twitter believe this is a ploy to bring her down.