Last week saw Vitor Belfort release the results of not only his February 7 random drug test (a test which led to his withdrawal from his UFC middleweight title bout), but also several other tests that Belfort took in the months following.

The first thing that likely jumps out to the observer is Vitor going from a testosterone level of 1472ng/dL on Feb 7, which is a very high number, to 142ng/dL on May 29, a very low number. However, the most intriguing number in the pages and pages of test results may be one that was blacked out by the Belfort camp.

The May 15 test (page 14 of the PDF) shows all levels but the testosterone level blacked out. The hematocrit level was one of the levels blacked out. However, they only blacked out the number, not the entire section, meaning that you can see that the level was listed in the "out of range" column.

Hematocrit tests the amount of red blood cells in a plasma sample. A low result would indicate anemia, a high result could be indicative of steroid use or blood doping.

Fluctuations in Hematocrit levels were one of the key factors in USADA's investigation into Lance Armstrong, as reported in the New York Daily News:

But before Armstrong left Italy, a doping control officer took a sample of the star cyclist's blood, which a laboratory test later revealed to have a 38.2% hematocrit ratio, a key marker of an athlete's endurance. The result was a little low for Armstrong, but it wasn't terribly unusual; hematocrit fluctuates, and in 2009 Armstrong's usually hovered between 40 and 43. What appeared strange is the spike in Armstrong's hematocrit score just a few weeks later. On June 16, when another blood sample was taken from Armstrong, his hematocrit was 45.7. That was high for Armstrong, and for most people. ... USADA, which apparently collected some of the tests from other anti-doping agencies, believes the fluctuations are more than suspicious. Combined with witness testimony about what allegedly went on behind closed doors on Armstrong's teams, the agency believes the 38 blood tests constitute objective proof that Armstrong doctored his blood using banned drugs or methods. Armstrong vigorously denies doping and has called USADA's pursuit of him a "vendetta" and a "lynching" and is fighting the organization in court. To the extent that the long-range analysis of Armstrong's blood values represents a "smoking gun," USADA will presumably point to both the suspicious hematocrit fluctuations but also other measurements such as reticulocyte percentages and hemoglobin.

Higher amounts of red blood cells (and higher hematocrit percentages), are associated in the PED world with everything from HGH to anabolic steroids to forms of blood doping--along with more "natural" causes such as congenital heart disease, significant dehydration..etc.

Victor Conte, the controversial former BALCO head turned anti-doping advocate, has stressed in the past just how severely steroids can increase hematocrit levels while discussing the fact that steroids can be beneficial to an athlete's endurance as well as strength, "As you know, steroids can increase red blood cell production and significantly increase Hematrocit levels. This has been the case with many professional bodybuilders that I’ve worked with. I’ve seen Hematocrit levels between 54% & 59% in bodybuilders that were not using EPO. So, steroids can help a fighter’s endurance by increasing their Hematocrit levels."

It is entirely possible that, given his low testosterone number of 165ng/dL, Belfort's hematocrit levels were out of range on the low side as opposed to the high. Anti-doping experts who spoke to Bloody Elbow suggested that no one number (not even low testosterone levels) are clear statements of a fighter being clean or dirty, especially if there are not full panel tests which include hGH testing as well as CIR and IRMS testing.

Given what we know, this certainly should not be taken as an accusation that Belfort was actively using steroids around the time of the May 15 test, but rather a note that there are still some important questions which need to be answered surrounding even the tests that Belfort and his camp chose to release.

Bloody Elbow reached out to the Belfort camp and asked to see the test with that number visible so that we can understand better why he returned a result that was out of range. As of the time of publication we had not received a response.

Belfort will go in front of the Nevada State Athletic Commission on the 17th for a licensing hearing at which time the NSAC will decide if they will grant Belfort a license to fight Chael Sonnen at UFC 175.