Kenya's former 1500m Olympic champion Asbel Kiprop was suspended Saturday for taking blood-booster EPO despite offering what the Athletics Integrity Unit (AIU) called an "a la carte menu of reasons why the charges should be dismissed".
The 29-year-old, a three-time world champion at 1500m, failed an out of competition test in November 2017.
He was provisionally suspended in 2018 ahead of the ruling by the AIU, the sport's independent integrity body.
The AIU said in its statement that Kiprop had "at various times and various formats...proposed a number of possible explanations" for the positive test.
It went on to state that at the hearing his representative, Katwa Kigen, presented an "a la carte menu of reasons why the charges should be dismissed."
mong these, the AIU said, were that the "EPO was naturally produced due to intense exercise at altitude," that it was produced by medication, that the test, or the analysis, was badly conducted or that the sample was spiked.
His ban is backdated to last February.
"I am totally innocent. It's unjust," Kiprop said last year.
The AIU statement added that while Kigen presented his arguments with "tenacity and charm" the International Association of Athletics Federations (IAAF) representative Ross Wenzel had argued that "none of the various reasons proposed...when subject to strict scrutiny had any plausibility."
The three-man panel agreed.
It concluded that high altitude could not explain the presence of EPO in the test and that Kiprop had produced no evidence to support the other possible explanations.
Kiprop, one of the biggest names in the country's stellar cast of middle-distance athletes, can still appeal to the Court of Arbitration for Sport.
Kiprop originally came second in the 1500m final at the 2008 Beijing Olympics but was upgraded when Rashid Ramzi tested positive for a performance-enhancing drug and was stripped of the gold medal.
A total of 138 Kenyan athletes have tested positive in anti-doping campaigns since 2004.
In 2016, Kenya were placed on the list of countries under IAAF surveillance.
And it was only after the adoption of a new anti-doping law just before the Rio 2016 Olympics that the country was removed from the list of "non-compliant" Wada nations.