Mass In Athletes Research Articles

ACE and angiotensinogen gene genotypes and left ventricular mass in athletes.

Genetic factors may be important in modifying heart size due to long-term athletic training. The significance of polymorphisms of genes of the renin-angiotensin system in myocardial mass in a population of athletes participating in different disciplines is not known. The angiotensin I-converting enzyme gene insertion/deletion (I/D) polymorphism, angiotensinogen gene M235T polymorphism and angiotensin II type 1 receptor gene A1166C polymorphism were determined in 83 male Caucasian endurance athletes and associated with left ventricular mass. No association with left ventricular mass was found for the polymorphisms of angiotensin I-converting enzyme gene I/D, angiotensinogen gene M235T and angiotensin II type 1 gene A1166C when studied separately. However, combined analysis of the angiotensin I-converting enzyme gene I/D polymorphism and angiotensinogen gene M235T polymorphism genotypes suggested an association with left ventricular mass (g m(-2)) (P = 0.023). Athletes with the angiotensin I-converting enzyme gene DD/angiotensinogen gene TT genotype combination had greater left ventricular mass compared with all other genotype combinations (179.8 +/- 26.1 g m(-2) vs. 145.2 +/- 27.3 g m(-2), P = 0.003). These results suggest an association of combined angiotensin I-converting enzyme gene I/D polymorphism genotypes, and angiotensinogen gene M235T polymorphism genotypes with left ventricular hypertrophy due to long-term athletic training. A synergistic effect of angiotensin I-converting enzyme gene DD genotype and angiotensinogen gene TT genotype on left ventricular mass in endurance athletes appears to occur.

Muscularity and the density of the fat-free mass in athletes.

The purpose of this study was to use estimates of body composition from a four-component model to determine whether the density of the fat-free mass (D(FFM)) is affected by muscularity or musculoskeletal development in a heterogenous group of athletes and nonathletes. Measures of body density by hydrostatic weighing, body water by deuterium dilution, bone mineral by whole body dual-energy X-ray absorptiometry (DXA), total body skeletal muscle estimated from DXA, and musculoskeletal development as measured by the mesomorphy rating from the Heath-Carter anthropometric somatotype were obtained in 111 collegiate athletes (67 men and 44 women) and 61 nonathletes (24 men and 37 women). In the entire group, D(FFM) varied from 1.075 to 1.127 g/cm3 and was strongly related to the water and protein fractions of the fat-free mass (FFM; r = -0.96 and 0.89) and moderately related to the mineral fraction of the FFM (r = 0.65). Skeletal muscle (%FFM) varied from 40 to 68%, and mesomorphy varied from 1.6 to 9.6, but neither was significantly related to D(FFM) (r = 0.11 and -0.14) or to the difference between percent fat estimated from the four-component model and from densitometry (r = 0.09 and -0.16). We conclude that, in a heterogeneous group of young adult athletes and nonathletes, D(FFM) and the accuracy of estimates of body composition from body density using the Siri equation are not related to muscularity or musculoskeletal development. Athletes in selected sports may have systematic deviations in D(FFM) from the value of 1.1 g/cm3 assumed in the Siri equation, resulting in group mean errors in estimation of percent fat from densitometry of 2-5% body mass, but the cause of these deviations is complex and not simply a reflection of differences in muscularity or musculoskeletal development.

Are gender differences in left ventricular mass in athletes related to 24-h blood pressure?

Are gender differences in left ventricular mass in athletes related to 24-h blood pressure?

Angiotensinogen gene M235T polymorphism predicts left ventricular hypertrophy in endurance athletes

OBJECTIVESWe studied whether left ventricular mass in athletes associates with polymorphisms in genes encoding components of the renin–angiotensin system.BACKGROUNDAdaptive left ventricular hypertrophy is a feature of the athlete’s heart. However, similarly training athletes develop left ventricular mass to a different extent, suggesting that genetic factors may modulate heart size.METHODSWe measured left ventricular mass by echocardiography in 50 male and 30 female elite endurance athletes aged 25 ± 4 (mean ± SD) years. Deoxyribonucleic acid samples were prepared for genotyping of angiotensinogen (AGT) gene M235T polymorphism, angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and angiotensin II type 1 receptor (AT1) gene A1166C polymorphism.RESULTSThe AGT gene M235T genotypes were significantly associated with left ventricular mass independently of blood pressure in both genders (p = 0.0036 for pooled data). TT homozygotes had greater mass compared with MM homozygotes in both men (147 ± 12 g/m vs. 132 ± 15 g/m, p = 0.032) and women (121 ± 12 g/m vs. 101 ± 13 g/m, p = 0.019). There was a gender difference in the relation between myocardial mass and AGT genotype, MT heterozygotes resembling MM homozygotes among women and TT homozygotes among men. The other studied gene polymorphisms were not associated with left ventricular mass.CONCLUSIONSAngiotensinogen gene M235T polymorphism is associated with the variability in left ventricular hypertrophy induced by endurance training, with athletes homozygous for the T allele having the largest hearts. We found no association between ACE gene I/D or AT1 gene A1166C polymorphisms and left ventricular mass.

Echocardiographic examination of cardiac structure and function in elite cross trained male and female Alpine skiers.

OBJECTIVE: To assess cardiac structure and function in elite cross-trained male and female athletes (Alpine skiers). METHODS: Sixteen athletes (10 male, six female) and 19 healthy sedentary control subjects (12...

Free carnitine and acetyl carnitine plasma levels and their relationship with body muscular mass in athletes.

The purpose of the present study was to investigate the relationship between plasma carnitine concentration and body composition variation in relation to muscular and fat masses since there is no experimentally proved correlation between plasma carnitine and body masses. We used bioelectric impedance analysis (BIA), to determine body composition and to have a complete physical fitness evaluation. The post-absorptive plasma free carnitine and acetyl carnitine plasma levels, body composition as Fat-Free Mass (FFM) and Fat Mass (FM) in kg, as well as in percent of body mass, were analysed in 33 healthy subjects. A significant negative correlation was found between plasma acetyl carnitine and FFM in weight (kg) as well as in percent of body mass (respectively p < 0.0001; p < 0.01); a significant positive correlation was found only between FM in percent and plasma acetyl carnitine (p < 0.01). The observed negative correlation between plasma acetyl carnitine and muscular mass variation might reflect an oxidative metabolic muscle improvement in relation to muscular fat free mass increment and might be evidence that muscle metabolism change is in relation to plasma acetyl carnitine concentration.

Bone mass in athletes during and after career

Bone mass in athletes during and after career

Left ventricular performance and ultrasonic myocardial quantitative reflectivity in endurance senior athletes: an echocardiographic study

Young elite athletes often show left ventricular hypertrophy, but normal values of quantitatively evaluated myocardial wall reflectivity. The aim of this study is to assess the acoustic pattern of ventricular wall reflectivity, as well as of systolic and diastolic function, in older endurance runners with increased left ventricular mass. For this purpose, 12 elite, senior isotonic athletes in full training and 11 normal, age-matched controls with sedentary life styles were studied. The following parameters were measured with a commercially available 2D echo-Doppler machine: end-diastolic diameter, diastolic septum thickness, left ventricular mass index, ejection fraction (by Teicholtz rule); peak E, peak A, E/A ratio, acceleration and deceleration time of mitral inflow velocity and isovolumic relaxation time. On-line radio frequency analysis was also performed to obtain quantitative operator-independent measurements of the integrated backscatter signal of the ventricular septum and the posterior wall. The integrated values of the radiofrequency signals were normalized for the pericardial interface and expressed in percent (% 2D-IB). In spite of the greater left ventricular mass in athletes versus normal controls (319 +/- 81 vs 225 +/- 63 g.m-2, P < 0.0005), there were no significant intergroup differences as regards end-diastolic diameter (50.7 +/- 5.1 vs 48.1 +/- 5.2 mm, P = ns), ejection fraction (75.5 +/- 9.3 vs 71.8 +/- 9.1%, P = ns), and 2D-IB of septum (22.2 +/- 6.9 vs 22.4 +/- 7.0, P = ns) and posterior wall (12.5 +/- 5.6 vs 13.1 +/- 2.8, P = ns).(ABSTRACT TRUNCATED AT 250 WORDS)

Proposed corrections in the KERR method on estimating total body weight and calculating muscle mass in athletes

Proposed corrections in the KERR method on estimating total body weight and calculating muscle mass in athletes

Glucocorticoid-mediated induction of glutamine synthetase in skeletal muscle

We studied the effect of glucocorticoids on glutamine synthetase in rat skeletal muscle in culture and in vivo. Dexamethasone, a synthetic glucocorticoid, caused striking, receptor-mediated increases in both glutamine synthetase activity and the steady-state glutamine synthetase mRNA level. This effect was observed in rat skeletal muscle cells in culture, as well as in rat muscles in vivo. Glucocorticoid-mediated induction of glutamine synthetase was blocked by androgenic/anabolic steroids at high doses, suggesting that anabolic steroids might have an anticatabolic mode of action in enhancing skeletal muscle mass in athletes. Further studies of the control of glutamine synthetase expression may shed light on mechanisms of muscle atrophy and hypertrophy.

Normal ultrasonic myocardial reflectivity with increased left ventricular mass in athletes: A tissue characterization study

Normal ultrasonic myocardial reflectivity with increased left ventricular mass in athletes: A tissue characterization study

The relationship of left ventricular function and mass in arterial hypertension. An echo and apexcardiographic comparison with sportsmen and controls.

Non-invasive assessment of left ventricular function by M-mode echocardiography and calibrated apex-cardiology was performed in 48 male hypertensives, without cardiac failure, 15 top class endurance athletes and 20 normotensive controls. The aim of the study was to assess the effect of left ventricular hypertrophy on left ventricular function and to determine whether similar abnormalities of left ventricular function occurred regardless of whether hypertrophy was due to hypertension or athletic activity. Both the athletes and the hypertensives showed significantly increased left ventricular posterior wall thickness and left ventricular mass compared to controls. Left ventricular hypertrophy was most marked in the athletes but despite this severe hypertrophy, their left ventricular function was normal and some ejection phase indices of left ventricular performance were moderately increased. In contrast, some of the patients with hypertension had markedly reduced left ventricular function assessed from ejection phase indices such as ejection fraction and mean VCF although there was a wide range of ventricular function within the group as a whole. The extent of the abnormalities did not correlate with the extent of hypertrophy in the individual hypertensive patients. Therefore, greatly increased left ventricular mass in athletes was not associated with abnormal left ventricular function and severely abnormal left ventricular function in hypertensives was not related to the extent of hypertrophy.

A pilot study on left ventricular dimensions and wall stress before and after submaximal exercise.

Left ventricle dimensions and wall stress were measured echocardiographically before and immediately after exercise in 14 athletes and 7 control subjects. Our findings suggest that afterload is an important determinant of cardiac performance and wall hypertrophy in athletes. In spite of major changes in heart rate and blood pressure, left ventricular wall stress remains unchanged following submaximal exercise, in trained and untrained hearts. It would appear that the changes in heart size during exercise are to a large extent limited in untrained ventricles, as smaller left ventricular dimensions are required, to "normalise" wall stress. This results in a lower stroke volume for a given stroke dimensional change. Consequently cardiac output is a function of heart rate rather than stroke volume in untrained subjects. The effect of increased muscle mass in athletes, is to permit larger left ventricular dimensions for a given afterload, thus stroke volume can be augmented. The increase h/R ratio suggests that afterload is more important than preload in the development of left ventricular hypertrophy in rowers and swimmers.

Nomograms for prediction of body density and total body fat from skinfold measurements.

Nomograms for prediction of body density and total body fat from skinfold measurements.