I was recently asked to give an interview to a US web
page – a link to the podcast can be found at the bottom of this blog [1]. In
part their interest was in a scientific view about testosterone doping in
veteran athletes. A triathlete – Kevin Moats – had failed a drug test for
testosterone. Moats claimed that he was taking the drug on his doctor’s advice
due to his low testosterone levels. However, he had no therapeutic use
exemption (TUE) so was banned.
This is an area I should have perhaps covered more in
my book. Although there is no general clinical agreement on when – or indeed if
- testosterone therapy should be given to older men, it is clear that in many
countries reporting to your doctor with fatigue, depression and low sex drive
can get you a prescription for anabolic steroids with relative ease.
This raises a number of issues:
1 Is there
a clinical need for testosterone replacement therapy?
In females there is a clear menopause and hormone
replacement therapy is a commonly accepted treatment to alleviate some of the
associated symptoms (though the risk/reward ratio of such a therapy is
controversial). In males there is no clear menopause. It is true that sex
hormone levels decline with age. However, there is no clear indication that
this is associated with adverse symptoms, not whether there can be reversed by
testosterone administration. But there
is clear anecdotal evidence of benefit. To get to the bottom of this, the US
National Institute on Aging has recently funded a large-scale clinical trial
(the T-Trial) involving 800 men age 65 and older with low testosterone levels
[2].
So to answer the first question testosterone may be
of clinical benefit as people get older, but the evidence is not yet clear cut.
2 Should
athletes on testosterone therapy be given a therapeutic use exemption (TUE)?
In sports drug testing the absolute testosterone
levels are not measured, as urinary excretion of the drug is so variable.
Instead the ratio of Testosterone:Epitestosterone in the urine is measured
(epitestosterone is an inactive form of the hormone that does not increase
muscle mass). This ratio is normally close to 1. Steroid doping will increase
the T levels, but not the E. If the T/E ratio then rises above 4 it triggers a
positive test. Carbon isotope ratio (CIR) testing can then confirm whether
artificial testosterone had been used (as the synthetic drug is synthesized from
plant sources it behaves differently to normal human testosterone in this
test). Someone on testosterone replacement therapy could therefore easily
trigger a positive test even if his absolute testosterone levels were not
abnormally high as he would have a high T/E ratio due to the presence of the
synthetic plant-derived testosterone.
So surely a TUE would be justified? Maybe so, but
there are two good arguments against this. First if raising your testosterone
levels to “normal” means raising them to those of a young person, is not this
in itself cheating compared to rival veteran athletes who choose not to supplement?
In which case allowing a TUE might put pressure on all athletes to supplement in
order to compete on a level playing field. Second, once you have the exemption
it would be a simple matter to increase the amount of steroids you take. This could
give rise to supraphysiological levels of anabolic steroids of the kind
used - and abused - by younger athletes.
Yet the doctor’s note would forgive all. I suspect this second pragmatic,
practical reason is why TUE’s in this field will be rarely – if ever – permitted.
3 Can
older athletes raise their testosterone levels without failing a doping test?
A quick look at any nutritional web site will reveal
a whole host of products that claim to be able to increase testosterone levels
“naturally”. Maca and Tribulus are two of those in current vogue. It is true
that increasing the body’s own metabolic pathways should not fall foul of the
testers. However, there are two problems with this approach. First athletes
should beware as many supplements contain other banned substances, either by
accident or design. But secondly, and equally as important, there is no
evidence that these products have any affect at all on testosterone levels.
Anecdotal evidence and personal testaments are no substitute for scientific
studies, which invariably show negative results [3, 4].
So to summarize: we don’t know whether testosterone
is clinically necessary, using it will get you banned and there are no
validated supplements that can help. As a 49-year-old fatigued male with a
somewhat lower sex drive than I had as a teenager, I am tempted to say “It
happens to us all as we get older: just get over it and enjoy your sport”. Or of
course take the therapy and compete for fun.
(these sentiments are not of course aimed at those
with very low testosterone levels caused by pathology or injury, where therapy
is clearly necessary and important).
[3 Srikugan,
L., Sankaralingam, A., and McGowan, B. (2011) First case report of testosterone
assay-interference in a female taking maca (Lepidium meyenii), BMJ case
reports 2011
[4] Gauthaman,
K., and Ganesan, A. P. (2008) The hormonal effects of Tribulus terrestris and
its role in the management of male erectile dysfunction--an evaluation using
primates, rabbit and rat, Phytomedicine : international journal of
phytotherapy and phytopharmacology 15, 44-54.