Cardiovascular Adaptations

In the ever changing and ever competitive field of sports, athletes are continuously looking for the competitive edge.  Recently, in the past few decades, blood doping, use of erythropoietin (epo for short) and high altitude training have all become more common practices by athletes to “get ahead” of their competition.

The first practice “Blood doping” refers to increasing the number of red blood cells(RBC) in ones circulatory system either through a blood transfusion or by taking a series of hormone therapeis such as epo.  Both of these practices, whether deemed by governing sports bodies as ethical or not, all employ some means of improving oxygen delivery to the muscles and in turn, can logically boost the muscles performance through an increased Vo2 max.  Double blind studies have shown that athletes who have been treated either with a blood transfusion or with hormone therapy have had increased Vo2 max while running tests on a treadmill in laboratories.  Blood doping is a controversial topic in the field of sports along with hormone therapies.  “EPO or erythropoiesis stimulating hormone, is a glycoprotein, formed by the kidneys and liver.  Epo appears in the plasma when peripheral tissues, especially the kidneys, are exposed to low oxygen concentrations.”  Increasing your RBC count through “unnatural” means such as epo therapy or blood transfusions is not the only way to increase cardiac output, some athletes have turned to altitude training.

Altitude training refers to training conducted at altitudes greater than sea level and typically falls for most athletes between seven to thirteen thousand feet above sea level.  Training in an environment with less oxygen can create a state of hypoxia (decreased oxygen) and in turn the body will respond in time by increasing the formed elements (hematocrit) or RBC’s in the blood stream to compensate for lower oxygen levels.  Many studies have been conducted around this mind set and to this day many varying results have left sports scientists in the dark about altitude training and its benefits.  One important aspect to note about training at altitude is that, at altitude athletes are more often than not unable to perform at the same intensity as they would be capable to attain at sea level, leaving them with a decline in fitness verses an increased RBC count and Vo2 max.  Medical doctors are now prescribing a solution to this called, train low and live high, in which athletes are able to train at lower altitudes in doing so, they maintain a level of fitness appropriate to the demands they will be placing on their bodies during peak performance and live at a higher altitude.  In doing so, creating the hypoxic state at which altitude fools the body into keeping RBC counts high.

Blood doping, hormone therapy and altitude training are all examples of forcing the body to make cardiovascular adaptations.  Cardiovascular adaption techniques come with a risk.  Anyone suffering from sickle cell anemia or any other form of blood disorder should beware.  These techniques can be dangerous to the individuals due to the shape, size, number and O2 carrying capacity of their RBC’s. This can cause serious health problems.  Blood doping and hormone therapy both incur risks such as myocardial infractions, hormone imbalance and can even result in death.  It is my opinion after conducting my research that ample training wether it be at altitude or not out ways the risks of performing blood transfusions to get ahead in a sport.  Hard work and dedication in a particular sport can pay off in physiological, anatomical and mental gains that would be non-attainable through other means.  Wether or not using your own blood to boost your athletic performance is considered cheating or not is up to sports authorities, I subscribe to the work hard play hard mentality.

Citations:

Effect of graded erythrocythemia on cardiovascular and metabolic responses to exercise.
Spriet LL, Gledhill N, Froese AB, Wilkes DL.
J Appl Physiol. 1986 Nov;61(5):1942-8.
PMID: 3781999 [PubMed - indexed for MEDLINE]

Effect of induced erythrocythemia on aerobic work capacity.
Buick FJ, Gledhill N, Froese AB, Spriet L, Meyers EC.
J Appl Physiol. 1980 Apr;48(4):636-42.
PMID: 7380690 [PubMed - indexed for MEDLINE]

Crowther, Greg. "Living High and Training Low." Living High and Training Low. Northwest Runner, Sept. 2000. Web. 28 Sept. 2012. .

"Human Anatomy &Physiology (9th Edition) [Hardcover]." Human Anatomy &Physiology (9th Edition): Elaine N. Marieb,Katja Hoehn: 9780321743268: Amazon.com: Books. N.p., n.d. Web. 01 Oct. 2012. .