Altitude Training and EPOLecture 19

The practice of altitude training and synthetic EPO doping is usually done by endurance athletes.

Altitude training has been shown to improve aerobic capacity and enhance recovery. This would be extremely important to an athlete competing in a multi-stage event like the Tour de France.

Altitude training:Traditionally athletes would live at High Altitude camps (8000ft above sea level) for several weeks before the event)More common practice now is to have athletes sleep in high altitude tents or live in high altitude houses.

How does high altitude training improve performance?At an altitude of 8000ft the air has ~75% of the O2 at sea level.Lower O2 concentrations in the air means that the partial pressure of O2 in the blood decreases.Lower partial pressure of O2 stimulates an up regulation of erythrocyte production (RBC) thus increasing the hemoglobin content of the blood

Hemoglobin carries O2in the blood to working muscles.

Athletes that live high and compete low (at sea level where there is normal O2 in the air) have increased carrying capacity of O2 and consequently greater O2 delivery to tissues. This increases aerobic performance and speeds up the recovery process.

Many studies have shown the benefit of altitude training on:Speed, power, endurance and recoveryOptimally: Live HIGH, train LOWThis is tough because its a long way up and down the mountain to get 8000ft down and back up.More Common: Live HIGH, train HIGHAlso tough because training intensity is impaired by the altitude. Athletes are also at-risk for altitude sickness.

Instead of trying to trying to manage living at high altitude companies commercially manufacture/sell high altitude systems.tents or houses that athletes live in or bring with them that simulate a high altitude environment (sleep for 10-12 hours) Tents have normal sea level pressure but reduced O2 in the air (15.3% vs. 21% O2)

High altitude products have shown increases in RBC and EPO concentrations in the body.

The use of high altitude performance strategy, although accepted to benefit performance, is controversial because the effect on RBC count decreases within several days at sea level.

To counteract the acuteness of high altitude training elite athletes often travel with their high altitude gear to sleep in so they can maintain their higher hematocrit levels.

Erythropoietin (EPO)Glycoprotein hormone that stimulates erythrocyte (RBC) precursors in the bone marrow. Produced by our kidneyRegulates RBC production

Synthetic EPO is available as a therapeutic agent produced by recombinant DNA technology in mammalian cell culture- used traditionally to treat anemia (decrease in the number of healthy RBC) as a result of cancer or chronic renal failure- also used as a common blood doping agent in endurance sports

Hypoxia: when O2 availability is limited. Altitude TrainingIncreased aerobic capacity

How EPO works:

EPOEPOEPOKidneyWhen O2 is LOWHigher O2 in the blood feedbacks to kidneysEPOO2 is normalBone (marrow not shown)

Use of EPO for athletic performance: same premise as high altitude training strategies.O2Performance

Use among athletes began in the 1980s but there was no test for it.

Excessive use of EPO leads to an overproduction of RBC that the blood becomes so thick it puts too much strain on the heart.

Evidence of EPO overuse among cyclists surfaced in the early 1990s when more than a dozen cyclists dies of heart failure in their sleep.

In 1998 a huge doping scandal at the Tour de France tainted the sport and forced cycling federations to implement more stringent testing measures. EPO use was initially tested for by measuring hematocrit concentrations. (this is the proportion of blood volume that is RBC)Normal is 41-50% for men. WADA enforced the legal limit of 50%Cyclists employed great doctors to keep their hematocrit levels at 49.9% with blood thinning infusions.

In 2000, a urine test for EPO was used to detect residues of pharmaceutical EPOTest is controversial: several athletes that have tested positive for EPO use have successfully had their cases overturned with a defense that the test was unreliable.

In 2006 new pharmaceutical EPO (Dynepo) is expected to be on the market. It is manufactured in human cells and would have an identical pattern to human glycosylation that is seen on natural EPOIt would be undetectable with the current method of testing.

The illegal blood doping era is likely over but legal ways to increase whole body hemoglobin levels to the ceiling of 49.9% as permitted will continue in the future.