Improved blood doping detection protects sport and athletes
9 August 2012
Blood doping has affected many high profile sports
events like the Tour de France. [Image: Flickr/Josh
The practice of blood doping has been widespread but
notoriously difficult to detect among Olympic athletes
since the 1980s. Improvements to the accuracy and relevance
of the test for blood doping by a University of Sydney
researcher could soon put an end to finger pointing, weak
excuses and suspicion in elite sports.
Dr Corinne Caillaud of the University's Faculty of Health
Sciences is working on a project to determine whether
current methods to detect performance-enhancing hormone
Erythropoetin (EPO) may incorrectly report false positive
cases, particularly in the context of the intense physical
exercise of elite athletes at top-level competitions such
as the Olympics.
EPO is a hormone used by endurance athletes to boost red
blood cell production to increase oxygen transport around
the body and improve aerobic performance. Use of the drug
exploded in popularity following the 1998 Tour de France,
when it was found in the hotel rooms and support vehicles
of competing teams.
"Blood doping can be achieved either via blood
transfusion or EPO injections. The performance enhancing
material is the blood itself, or a hormone (EPO) that is
naturally produced by the body. This is why it can be so
difficult to detect," says Dr Caillaud.
One of first steps taken by anti-doping bodies to fight EPO
abuse was to set a 'non-participation threshold',
which meant that no athlete could present to competition
with a volume percentage of red blood cells, or
'haematocrit', higher than 51. The average
haematocrit for an adult male is 42 to 51 percent.
Dr Caillaud believes this threshold was both unfair for
athletes with a naturally high haematocrit and inefficient
to stop doping.
The more efficient testing methods currently used by the
World Anti-Doping Agency include both urine detection of
recombinant EPO and a 'blood passport', which keeps
a long-running, continuous record of athletes' blood
test results to detect inconsistencies and evidence of
However, there is still uncertainty over false positives
produced using the current testing methods. Dr
Caillaud's research tackles the question of blood and
urine tests that return false positive cases, particularly
a common justification that strenuous, prolonged exercise
in hot conditions can produce false positives.
"We need more data on the impact of strenuous physical
exercise on the critical markers used to detect blood
doping," she says.
"Athletes and officials need to be able to trust the
detection process and be reassured no false positive
results will be returned. While you or I would barely
notice the changes EPO makes to our bloodstreams, when
you're running, swimming or cycling long distances it
can make the difference between winning and losing,"
Dr Caillaud says.
In a clinical trial, Dr Caillaud examined EPO levels in
elite cyclists training in very hot conditions over a
number of days for nine weeks.
Preliminary results from her work have so far produced no
evidence of any relationship between intense exercise in
hot weather and false positive results, which could provide
much-needed credibility and authority for the World
Anti-Doping Agency's current methods.
Dr Caillaud's work responds to an alarming lack of
research on the impact of physical exercise on markers of
EPO abuse in the context of elite sports.
"It's vital that we continue to research drug
abuse in sport to determine the real effect of drugs on
human performance, develop new detection methods and most
importantly protect the health of the athletes."