HRE wrote:
Two Finnish steeplechasers, Mikko Ali Leppilampa and Jouko Kuha, were known to have blood doped in the late 60s. Kuha actually had the world record briefly. So the technique was known before Viren came along but not very widely...
I wouldn't be too convinced about the accuracy of the alleged 1968 transfusion of Jouko Kuha even when some reliable people such as Kari Sinkkonen (coach of Pekka Vasala) have referred to it in passing later. Because the information is second or third-hand gossip, it could've been simply iron injection and it isn't clear why Juha Väätäinen was treated with iron injections in 1969 if transfusion had been applied with success earlier.
About Viren, it is interesting that the Swedish discus star Ricky Bruch claimed in 1977 or 1978 that a member of the Finnish team had told him that Viren had been treated with a transfusion at the '76 games, and it is equally interesting that Finnish steeplechaser Mikko Ala-Leppilampi claimed in 1981 that he "read" certain indirect comments made to him in 1972 by the Finnish team doctor Pekka Peltokallio in a such a manner that Lasse Viren had been treated with blood doping. Ala-Leppilampi went later on to claim that a Finnish endurance runner not treated with a transfusion in the 1970's was an exception.
It still should be taken into account that the guy's reliability was much in doubt, because Ala-Leppilampi sold his confession about his own blood doping use to a sensational tabloid under heavy financial pressures, and at least a portion of what he told was simply inaccurate. He claimed - for instance - that a transfusion enhances 3000m steeplechase time by 20 seconds, but he improved his own PR by only 3.7 seconds after 1971 when he told he got introduced into the mysterious brotherhood of blood. And his account even changed on the detail whether he used the method 3 or 5 times when he recalled his career later.
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As one interesting anecdote, I had an opportunity to discuss the subject with the journalist who was the first one to contact the Finnish team doctor Pekka Peltokallio in 1981 after Ala-Leppilampi had made his confession and mentioned the team doctor by name implying that Peltokallio administered the transfusion to him in 1972. The doctor confessed that the 1972 blood doping incident was accurate even when he insisted that the allegations about the other Finns weren't true and he "was under no obligation to tell where and how the operation was done". Correspondingly the journalist wrote an article titled "EVEN WHEN THE SPORTS LEADERS DENY IT, BLOOD DOPING IS RAMPANT IN FINLAND".
While the impression of the journalist not-too-long time ago was that Ala-Leppilampi was mostly reliable, he wanted to emphasize to me that he always felt that Lasse Viren hadn't blood doped based on his character.