Background: Soluble transferrin receptor (sTfr) is a new marker of iron status and erythropoietic activity. It has been included in multivariable blood testing models for the detection of performance enhancing erythropoietin misuse in sport. Objective: To evaluate the effect of different types and volumes of physical activity on sTfr concentration, variables of iron status (ferritin, transferrin, iron, and protein), and haematological indices. Methods: Thirty nine subjects were divided into three groups: 1, untrained (n = 12); 2, moderately trained (n = 14); 3, highly trained (n = 13, seven men, six women). Groups 1 and 2 carried out two exercise tests: an incremental running test until exhaustion (test A) and a 45 minute constant speed running test at 70% VO 2 MAX (test B). Group 3 performed three days (women) or four days (men) of prolonged aerobic cycling exercise. The above variables together with haemoglobin and packed cell volume were analysed in venous blood samples before and after exercise. Changes in blood and plasma volume were estimated. Results: sTfr levels were slightly increased in trained and untrained subjects immediately after test A. Test B and aerobic exercise had no significant effect on sTfr. Ferritin levels were increased after the laboratory tests for trained and untrained subjects and after prolonged aerobic exercise in male cyclists. Transferrin was increased significantly in trained and untrained subjects after both laboratory tests, but remained unchanged after prolonged exercise. Plasma and blood volumes were decreased after the laboratory tests but increased after aerobic exercise. No differences in the variables were observed between trained and untrained subjects with respect to response to exercise. Conclusion: The changes in sTfr and the variables of iron status can be mainly attributed to exercise induced changes in volume. Taking these limitations into account, sTfr can be recommended as a marker of iron deficiency in athletes.

During recent years the echocardiographic procedure has been extended regarding the evaluation of left ventricular myocardial function during exertion. During exercise echocardiography, body position is important for the correct assessment of cardiac dimensions and function, particularly for the measurement of the cross-sectional diameters of the left ventricle and diastolic myocardial function. Reliable parameters of left ventricular function during exercise are left ventricular ejection fraction and endsystolic left ventricular volume, but not enddiastolic left ventricular volume. The increase of left ventricular ejection fraction during exercise up to submaximal exertion primarily results in a reduction of endsystolic left ventricular volume and partially in a simultaneous increase of enddiastolic left ventricular volume. In several cross-sectional studies comparing untrained and endurance trained hearts a higher diastolic filling rate, a higher maximal blood flow velocity of early diastolic passive left ventricular filling and a higher early diastolic filling fraction at rest and during exercise could be proved in endurance trained hearts. These training-induced adaptations of diastolic left ventricular function have been confirmed by a longitudinal study with primarily untrained young and older healthy subjects performing a heart rate controlled endurance training programme. Stress echocardiographic and simultaneous spiroergometric investigations indicated a correlation between the diastolic left ventricular function and the maximal oxygen uptake. The currently available data on the sensitivity, the intraobserver and interobserver variability of Doppler echocardiography have shown that this non-invasive procedure is valid for the evaluation of the systolic and the diastolic myocardial function at rest and during exercise. However, the procedure is limited to patients where the ultrasonographic assessment of cardiac structures is not considerably restricted. Furthermore, the reliability of stress Doppler echocardiography is dependent considerably on the practical skills of the observer.

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Background: Hereditary haemochromatosis (HH) is the most common genetic disease with a prevalence of 1:200–1:400 in Northern Europe. In most cases HH is caused by two mutations of the HFE gene (H63D and C282Y). As haemochromatosis leads to elevated iron uptake it is conceivable that blood donors with HFE mutation might be refused from giving a donation less often than donors without the mutation. Therefore, HFE mutations might be overrepresented among frequent blood donors. This study aimed to determine the prevalence of HFE mutations in a blood donor population from Southwestern Germany. Material and Methods: The HFE mutations H63D and C282Y were analysed in 3,015 samples by PCR-SSP typing. Age and sex of the donors were considered as well as the number of blood donations. Results: No differences in frequency of both mutations could be observed between first-time and frequent donors. The prevalence of the H63D mutations was higher among female than male donors: 28.6 vs. 24.3%; p = 0.007, whereas the genotype frequencies containing the C282Y mutation were similar between male and female donors. Compared to populations from Australia or South Wales the prevalence of the C282Y mutation was lower in our blood donor population (14.8–15.8 vs. 9.0%; p < 0,0001). Conclusions: The proposed overrepresentation of HFE mutations among frequent donors could not be confirmed. However, we found a higher prevalence of the H63D mutation in female donors than in male donors. One might therefore presume that blood donation in addition to the loss of blood due to menstruation is compensated more adequately in female H63D mutation carriers than in females without H63D mutation. This mutation seems to elevate the iron uptake so that female mutation carriers may have a higher chance to be admitted for blood donation. Individuals with diagnosed haemochromatosis-linked mutations should be informed about the potential health benefit from periodical blood donation and the admittance of such donors should be considered in Germany.

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