Establishment of Blood Screening Protocols for Collegiate Endurance Athletes 'Literature Review' chapter
- Length: 9 pages
- Sources: 12
- Subject: Sports
- Type: 'Literature Review' chapter
- Paper: #5445918
Excerpt from 'Literature Review' chapter :
Establishment of Blood Screening Protocols for Collegiate and Endurance Athletes
The goal of this action research proposal is to establish blood screening for endurance athletes at the college, which the researcher is employed at as there is currently no system in place by which the athletic department, athletic training room, and health center work together to screen athletes that exhibit symptoms of non-anemic iron deficiency.
The standard testing protocols to determine anemia at most health centers do not adequately diagnose non-anemic iron deficiency in elite endurance athletes.
There is a need for standard testing protocols at the college health centers for accurate diagnosis of non-anemic iron deficiency in elite endurance athletes.
The work of Eichner (2001) entitled "SSE #81: Anemia and Blood Boosting" states that athletes, "especially endurance athletes, tend to have slightly low hemoglobin levels as judged by general population norms." Eichner reports that low blood hemoglobin concentration "…defines anemia, this has been called sports anemia. But sports anemia is a misnomer because in most such athletes -- especially men -- the low hemoglobin level is a false anemia. The total volume of red cells in the body is normal, not low. Hemoglobin level is decreased because aerobic exercise expands the baseline plasma volume; this reduces the concentration of red cells, which contain the hemoglobin. In other words, the naturally lower hemoglobin level of an endurance athlete is a dilutional pseudoanemia." (Eichner, 2001) Pseudoanemia is stated to be "…an adaptation to hemoconcentration that occurs during workouts. Vigorous exercise acutely reduces plasma volume by 10-20% in three ways. One, a rise in blood pressure and muscular compression of venules boost the fluid pressure inside the capillaries of the active muscles. Two, generation of lactic acid and other metabolites in muscle increases tissue osmotic pressure. These forces drive plasma fluid, but not red cells, from blood to tissues. Three, some plasma water is lost in sweat." (Eichner, 2001) Renin, aldosterone and vasopressin are released which conserve water and salt. In addition, albumin is added to the blood. The result is that baseline plasma volume expands and even one single round of intense exercise may expand the plasma volume up to 10% in a 24-hour period. (Eichner, 2001) According to Eichner it is common for an endurance athlete to have a hemoglobin concentration of "1 g/dL or even 1.5 g/dL below 'normal'." (2001) The recognition of this as pseudoanemia is dependent on the setting as well as exclusion of other anemias. Plasma volume changes quickly depending on the level of exercise therefore athletes who are in training the most have the lowest levels of hemoglobin's when daily workouts cease they have a rising hemoglobin level. Stated as key to aerobic fitness is pseudonanemia since the rise in plasma volume in addition to the athlete's heart adapting increasing the cardiac stroke volume which is stated to compensate for the fall in the concentration of hemoglobin per unit of blood which results in more oxygen being delivered to the muscles. Sports anemia is reported to be a false anemia and it is stated that exertional hemolysis nearly never causes anemia therefore iron deficiency is the leading cause of anemia in athletes and as well is reported to be a common cause of fatigue in female athletes. Insufficient can lead to low hemoglobin as it is a "critical component of hemoglobin." (Eichner, ) Eichner (2001a) reports that patients with anemia "feel fatigued only with exertion." When anemia is mild in nature, Eichner reports that the only thing that will unmask the anemia is strenuous exercise. Eichner and Scott (1998) report
"This was the case in three college athletes, all initially difficult to diagnose (Eichner & Scott, 1998). One was an elite runner who began losing races. Another was a softball player who saw a cardiologist for spells of fast heartbeat and breathlessness in training. The third was a basketball player who fell behind in training and was called an underachiever. In each case, the culprit was loss of stamina from iron deficiency anemia." (Eichner and Scott, 1998)
Reported as well by Eichner (2001) is that in a recent survey of 25,000 individuals in the United States findings show that 10% of young women are iron deficient and another 3 to 5% of young women are anemic. Iron deficiency among young men is reported to be rare. The survey is stated to have "…defined anemia in women as hemoglobin <12 g/dL. This conventional cutoff ignores that anemia is relative -- a point rediscovered often in sports medicine, as in two recent studies. In one, young women with low plasma ferritin (a marker for body iron stores) but hemoglobin >12 g/dL were given iron or placebo for 6 weeks as they trained. Those on iron grew fitter and cycled faster. Hemoglobin tended to rise on iron, and this rise improved "energetic efficiency." Conclusion: Women with hemoglobin >12 g/dL may be "functionally anemic." (Hinton, et al., 2000 in Eichner, 2001) Reported as well is that researchers "…also gauged VO2 max in two groups of young women called "nonanemic" because hemoglobin was >12 g/dL (Zhu et al., 1997). One group was iron depleted (ferritin <12 mcg/L); the other not. The former group had a lower VO2 max than the latter. But the former group also had a lower hemoglobin (mean 13.6 g/dL vs. 14.5 g/dL). So although all the iron-deplete women had hemoglobin >12 g/dL, they were anemic compared to the iron-replete women." (Eichner, 2001) Anemia is stated to be "relative" in that in the studies described "…slight differences in hemoglobin levels, all >12 g/dL, affected athletic performance. Anemia is best defined as a subnormal hemoglobin level for the individual. For example, a female athlete with hemoglobin 13 g/dL is anemic if her normal value is 14 g/dL. No firm cutoff value defines anemia." (Eichner, 2001) Iron deficiency anemia is reported to be "more common than surveys suggest. The more an athlete asks of her body, the more likely she is to feel exertional fatigue if she has mild anemia. Because of this, female athletes can benefit from regular screening. At the University of Oklahoma, we screen all female athletes yearly for hemoglobin and ferritin. We find up to 10-20% or more of first-year female athletes iron deficient. Many of these are anemic, some with hemoglobin <12 g/dL, some >12 g/dL." (Eichner, 2001) It is reported that the iron deficiency was found in 20% of varsity female volleyball and basketball players with hemoglobin <12 g/dL and as well 50% of female soccer players were found to have iron deficiency anemia. However, on iron "hemoglobin rose to 15.1 g/dL and her stamina improved." (Eichner,2001) Iron deficiency anemia is mild and subtle among female athletes compared to being rare among male athletes, therefore, male athletes are not screened for anemia. Eichner questions where athleticism is that which causes iron deficiency or whether it simply unmasks iron deficiency and states that "odds favor the later." (2001) It is reported that approximately 2% of marathoners or triathletes "…have blood in their stools following a race and 20% of distance runners have occult blood in the first stool post-race." (Eichner, 2001) Diagnosis of iron deficiency anemia is stated to be as follows: (1) Low or borderline hemoglobin level but as high as 13-13.5 g/dL in women can qualify; (2) Smaller than normal red cells; and (3) low serum ferritin, often <12 mcg/L. (Eichner, 2001) Eichner states that therapy is "…ferrous sulfate, 325 mg two or three times a day with meals. After a delay of a few days, hemoglobin should rise about 1 g/dL each week. Hemoglobin should be halfway to normal in three weeks and fully normal in two months." (2001)
The work of Fallon ( ) entitled "Utility of Hematological and Iron-Related Screening in Elite Athletes" reports that a paucity of prospective studies exist related to the utility of screening of hematological and iron-related variables in elite athlete populations. Hematological and iron-related variables have been documented in athletes participating in a wide variety of sports, but the clinical and performance-related significance of screening results in elite populations has not been documented." (Fallon, ) It is reported that in two large studies of preparticipation health screening that there was no mention of blood analysis and it was not included in the evaluation. Reported as well is that only one study reported having "conducted retrospectively in 1067 college athletes, assessed the value of screening for hematological variables. The authors measured white blood cell count (WCC), hemoglobin, mean corpuscular volume (MCV), and platelet count in both males and females and concluded that the only useful test was that for hemoglobin. The aspect of hematological and biochemical screening that is most justifiable is that of anemia. In athletes, as in the general population, anemia is most frequently associated with iron deficiency." (Fallon, )
Garza et al. (1997) tested the clinical value of serum ferritin tests in endurance athletes and concluded that "the literature does not justify routine measurement of ferritin as an independent marker…