Norimitsu Kinoshita

Long-Term Clinical Consequences of Intense, Uninterrupted Endurance Training in Olympic Athletes

OBJECTIVES The aim of this study was to assess incidence of cardiac events and/or left ventricular (LV) dysfunction in athletes exposed to strenuous and uninterrupted training for extended periods of time. BACKGROUND Whether highly intensive and uninterrupted athletic conditioning over a long period of time might be responsible for cardiac events and/or LV dysfunction is unresolved. METHODS We assessed clinical profile and cardiac dimensions and function in 114 Olympic athletes (78% male; mean age 22 +/- 4 years), free of cardiovascular disease, participating in endurance disciplines, who experienced particularly intensive and uninterrupted training for 2 to 5 consecutive Olympic Games (total, 344 Olympic events), over a 4- to 17-year-period (mean 8.6 +/- 3 years). RESULTS Over the extended period of training and competition, no cardiac events or new diagnoses of cardiomyopathies occurred in the 114 Olympic athletes. Global LV systolic function was unchanged (ejection fraction: 62 +/- 5% to 63 +/- 5%; p = NS), and wall motion abnormalities were absent. In addition, LV volumes (142 +/- 26 ml to 144 +/- 25 ml; p = 0.52) and LV mass index (109 +/- 21 g/m(2) to 110 +/- 22 g/m(2); p = 0.74) were unchanged, and LV filling patterns remained within normal limits, although left atrial dimension showed a mild increase (37.8 +/- 3.7 mm to 38.9 +/- 3.2 mm; p < 0.001). CONCLUSIONS In young Olympic athletes, extreme and uninterrupted endurance training over long periods of time (up to 17 years) was not associated with deterioration in LV function, significant changes in LV morphology, or occurrence of cardiovascular symptoms or events.

Aortic root dilatation among young competitive athletes: Echocardiographic screening of 1929 athletes between 15 and 34 years of age

BACKGROUND Aortic dilatation can be lethal for young competitive athletes. The prevalence among athletes is not known, however, and thus a reasonable approach to early recognition remains uncertain. METHODS AND RESULTS Echocardiograms of 1929 normotensive athletes 15 to 34 years of age were analyzed. Five (0.26%) athletes had aortic dilatation; 4 of the 5 played basketball. This made the prevalence of aortic dilatation 0.96% (4 of 415) among basketball and volleyball players, who represented a population of especially tall athletes. Tallness aside, only 2 of the 5 athletes had features of Marfan syndrome. Among the athletes without aortic dilatation, the relation between body surface area and aortic root dimension was nonlinear and best described with a quadratic regression model. Athletes with aortic dilatation fell well outside the 95% confidence interval. CONCLUSION Because a higher incidence of aortic dilatation is to be anticipated among very tall athletes, inclusion of echocardiography in screening before participation in certain sports should be considered.

Unusual left ventricular dilatation without functional or biochemical impairment in normotensive extremely overweight Japanese professional sumo wrestlers

To explore the physiologic limit of left ventricular (LV) enlargement, we performed echocardiography and air displacement plethysmography to respectively assess LV dimension and function and the body composition of Japanese professional sumo wrestlers. After excluding subjects with cardiovascular disease, hypertension, plasma brain natriuretic peptide (BNP) > or =17.9 pg/ml, diabetes mellitus, or asthma, 331 subjects (mean +/- SD age, 21.6 +/- 3.7 years; height 179.2 +/- 5.3 cm; weight 1,17.9 +/- 21.5 kg; percent fat, 29.6 +/- 6.6%) were analyzed. LV end-diastolic dimension averaged 58.4 +/- 3.7 mm and was within the generally regarded normal limit (< or =54 mm) in 14.5% of subjects, but was > or =60 mm in 41.1% of subjects. LV septal and posterior wall thicknesses were 10.3 +/- 0.9 and 10.2 +/- 0.9 mm, respectively. Peak E- and A-wave velocities, E/A ratio, LV fractional shortening, and BNP were 96 +/- 16 and 51 +/- 13 cm/s, 2.0 +/- 0.7, 33.5 +/- 4.5%, and 3.1 +/- 3.7 pg/ml, respectively. LV end-diastolic dimension was not correlated with these indexes of LV function or with plasma BNP levels, but was significantly correlated with height, weight, body surface area, fat-free mass, and fat mass. These results show that among very large, highly trained, professional athletes, LV end-diastolic dimension frequently exceeds the traditionally accepted upper limit of normal for the general population. This increase in LV end-diastolic dimension may thus represent an extreme example of the physiologic adaptation of the athletes heart.

Peak aerobic performance and left ventricular morphological characteristics in university students

ObjectiveTo determine whether a relationship exists between left ventricular morphology and aerobic capacity in large numbers of male university students with a physically inactive and active life style. DesignA prospective study. SettingSports medicine research center. ParticipantsEleven sedentary normal-weight university students, 17 sedentary overweight university students, and 215 university athletes. Main Outcome MeasuresAfter the echocardiographic examination, an incremental treadmill exercise test until exhaustion was performed to measure peak oxygen uptake (VO2). ResultsIn sedentary students, absolute peak VO2 in the overweight students was slightly higher than that in normal-weight students (3,024 vs. 2,912 ml/min). Relative peak VO2 (ml/min/kg) was highly negatively correlated with body mass index (kg/m2) in a total of 28 sedentary students. The correlation between absolute peak VO2 and left ventricular dimension was weak in the sedentary overweight students; however, a correlation coefficient of 0.55 was obtained in athletic students. A stepwise multiple regression showed significant determinants of absolute peak VO2 in athletic students for body surface area (45%), left ventricular dimension (7%), and certain sports (6%). ConclusionsA physically active life style plays a role in increasing both aerobic capacity and left ventricular enlargement. Body size appeared to be a potent stimulus to left ventricular enlargement.

Recognition of left ventricular hypertrophy in new recruits of professional sumo wrestling

The efficacy of electrocardiography (ECG) in the diagnosis of left ventricular (LV) hypertrophy in 890 males, newly recruited to Japanese professional sumo wrestling (15.9 +/- 1.8 years of age, 177.8 +/- 4.7cm, 107.3 +/- 4.7kg), was tested by comparing simple, widely employed ECG criteria (Sokolow-Lyon chest and limb lead voltages and Cornell voltage with repolarisation criteria) with echocardiographic evaluations of LV mass indexed to body surface area. LV hypertrophy was defined as a LV mass index > 2 SD above the mean value obtained from 115 age-matched, normotensive, sedentary, male controls. The prevalence of LV hypertrophy as determined by echocardiography was 9.0% the entire group and was 8.3% among the 484 normotensives. The sensitivities of the three ECG criteria were < or = 36.0%, and their specificities were 70.0-99.0%. In contrast to the Sokolow-Lyon chest lead criteria, the diagnostic performance of the Cornell criteria was little affected by body mass index (BMI), and stepwise regression revealed that BMI did not significantly correlate with Cornell voltage. Still, the diagnostic efficacy of ECG was not sufficient to merit its use for primary recognition of LV hypertrophy among professional sumo wrestlers. Indeed, LV hypertrophy will likely go undetected by ECG in most overweight muscular athletes.