Determinants of LV mass in athletes: the impact of sport, constitutional traits and cardiovascular risk factors.

BACKGROUND: Whether cardiovascular (CV) risk factors might impact Left Ventricular (LV) mass in athletes is unknown. METHODS: The impact of CV risk factors (Total/LDL cholesterol, triglycerides, positive family history, smoking, body fat, blood pressure), constitutional characteristics (age, sex, body mass index) and type of sport was assessed in 1111 Olympic athletes. RESULTS: Multivariate logistic regression analysis demonstrated a significant impact: BMI ≥ 30 kg/m2 (odds ratio [OR] = 2.8. 95° Confidence Interval [CI] 0.9-13.7; < 0.001; in males); age ≥ 20-year (OR = 2.1, CI 1.4-3.3; p < 0.001) in males; (OR = 2.3; CI 1.4-3.7) in females; systolic blood pressure ≥ 130 mmHg (OR = 1.1, CI 1.01-1.16; p < 0.001) in males; (OR = 1.03; CI 1.01-1.06; p < 0.03) in females; diastolic ≥ 85 mmHg (OR = 1.1, CI 1.03-1.2; p = 0.003) in males; (OR = 1.05, CI 1.02-1.08, p < 0.001) in females. No association was found for family history, smoking, body fat, LDL, total cholesterol, triglycerides. Overall, constitutional traits explain > 60% of the LV mass. Sport explains on average 14%, but large differences existed among disciplines, i.e., endurance showed the highest impact (55%, mixed: 20%, power: 17%, skill: 8%; p < 0.001). CONCLUSION: LV mass in athletes is largely governed by constitutional traits and type of sport, and independent from CV risk factors, except for systolic and diastolic blood pressure. Overall, constitutional traits explain more than 60% of LV mass. The impact of sport is largely different in relation to the discipline, and highest in endurance, moderate mixed and power and mild in skill disciplines.

Pre-participation health evaluation in adolescent athletes competing at Youth Olympic Games: proposal for a tailored protocol.

OBJECTIVE: To promote sports participation in young people, the International Olympic Committee (IOC) introduced the Youth Olympic Games (YOG) in 2007. In 2009, the IOC Consensus Statement was published, which highlighted the value of periodic health evaluation in elite athletes. The objective of this study was to assess the efficacy of a comprehensive protocol for illness and injury detection, tailored for adolescent athletes participating in Summer or Winter YOG. METHODS: Between 2010 and 2014, a total of 247 unique adolescent elite Italian athletes (53% females), mean age 16±1,0 years, competing in 22 summer or 15 winter sport disciplines, were evaluated through a tailored pre-participation health evaluation protocol, at the Sports Medicine and Science Institute of the Italian Olympic Committee. RESULTS: In 30 of the 247 athletes (12%), the pre-participation evaluation led to the final diagnosis of pathological conditions warranting treatment and/or surveillance, including cardiovascular in 11 (4.5%), pulmonary in 11 (4.5%), endocrine in five (2.0%), infectious, neurological and psychiatric disorders in one each (0.4%). Based on National and International Guidelines and Recommendations, none of the athletes was considered at high risk for acute events and all were judged eligible to compete at the YOG. Athletes with abnormal conditions were required to undergo a periodic follow-up. CONCLUSIONS: The Youth Pre-Participation Health Evaluation proved to be effective in identifying a wide range of disorders, allowing prompt treatment, appropriate surveillance and avoidance of potential long-term consequences, in a significant proportion (12%) of adolescent Italian Olympic athletes.

Low prevalence of cardiac abnormalities in competitive athletes at return-to-play after COVID-19.

OBJECTIVE: to evaluate the prevalence of cardiac involvement after COVID-19 in competitive athletes at return-to-play (RTP) evaluation, following the recommended Italian protocol including cardiopulmonary exercise test (CPET) and 24-Hour Holter monitoring. DESIGN AND METHODS: this is a single centre observational, cross-sectional study. Since October 2020, all competitive athletes (age ≥ 14 years) evaluated in our Institute after COVID-19, prior RTP were enrolled. The protocol dictated by the Italian governing bodies included: 12­lead ECG, blood test, CPET, 24-h ECG monitoring, spirometry. Cardiovascular Magnetic Resonance (CMR) was performed based on clinical indication. RESULTS: 219 consecutive athletes were examined (59% male), age 23 years (IQR 19-27), 21% asymptomatic, 77% mildly symptomatic, 2% with previous pneumonia. The evaluation was performed after a median of 10 (6-17) days from negative SARS-CoV-2 swab. All athletes showed a good exercise capacity at CPET without cardiovascular and respiratory limitations. Uncommon premature ventricular contractions (PVCs) were found in 9.5% (n = 21) at CPET/Holter ECG monitoring. Two athletes (0.9%) were diagnosed with acute myocarditis (by CMR) and another one with new pericardial effusion. All the three athletes were temporally restricted from sport participation. CONCLUSIONS: Myocarditis in competitive athletes screened after COVID-19 resolution was detected in a low minority of the cases (0.9%). However, a non-negligible prevalence of uncommon PVCs (9%) was observed, either at CPET and/or Holter ECG monitoring, including all athletes with COVID-19 related cardiovascular abnormalities.

Periodic health evaluation in athletes competing in Tokyo 2020: from SARS-CoV-2 to Olympic medals.

Background: The Tokyo Olympic games were the only games postponed for a year in peacetime, which will be remembered as the COVID-19 Olympics. No data are currently available on the effect on athlete's performance. Aim: To examine the Italian Olympic athletes who have undergone the return to play (RTP) protocol after COVID-19 and their Olympic results. Methods: 642 Potential Olympics (PO) athletes competing in 19 summer sport disciplines were evaluated through a preparticipation screening protocol and, when necessary, with the RTP protocol. The protocol comprised blood tests, 12-lead resting ECG, transthoracic echocardiogram, cardiopulmonary exercise test, 24-hour Holter-ECG monitoring and cardiovascular MR based on clinical indication. Results: Of the 642 PO athletes evaluated, 384 participated at the Olympic Games, 254 being excluded for athletic reasons. 120 athletes of the total cohort of 642 PO were affected by COVID-19. They were evaluated with the RTP protocol before resuming physical activity after a mean detraining period of 30±13 days. Of them, 100 were selected for Olympic Games participation, 16 were excluded for athletic reasons and 4 were due to RTP results (2 for COVID-19-related myocarditis, 1 for pericarditis and 1 for complex ventricular arrhythmias). Among athletes with a history of COVID-19 allowed to resume physical activity after the RTP and selected for the Olympic Games, no one had abnormalities in cardiopulmonary exercise test parameters, and 28 became medal winners with 6 gold, 6 silver and 19 bronze medals. Conclusions: Among athletes with COVID-19, there is a low prevalence of cardiac sequelae. For those athletes allowed to resume physical activity after the RTP evaluation, the infection and the forced period of inactivity didn't have a negative impact on athletic performance.

Efficacy and Safety of a Combined Aerobic, Strength and Flexibility Exercise Training Program in Patients with Implantable Cardiac Devices.

Purpose: The "FIDE Project" (Fitness Implantable DEvice) was organized by the Institute of Sports Medicine and Science and the World Society of Arrhythmias with the aim of demonstrating the usefulness of exercise training in improving functional capacity in patients with implantable cardiac devices. Materials and Methods: Thirty sedentary patients were selected for the project (25 males and 5 females), with a mean age of 73 ± 5 years (range 44-94 years). Twenty-five were implanted with a Pacemaker (PM) and five with an Implantable Cardioverter Defibrillator (ICD). Atrial fibrillation/atrial flutter was present in ten (34%) patients, post-ischemic dilated cardiomyopathy in five (17.2%), sick sinus syndrome in six (20,7%), complete atrium-ventricular block in six (20.7%), hypertrophic cardiomyopathy in one (3.4%) and recurrent syncope in one (3.4%). The baseline assessment comprised cardiovascular examination, resting and stress ECG, cardiopulmonary exercise testing (V ̇O2peak), strength assessment of different muscle groups, and a flexibility test. The same measurements were repeated after 15-20 consecutive training sessions, over a 2-month period. The exercise prescription was set to 70-80% of HRR (Heart rate reserve) and to 50-70% of 1RM (1-repetition maximum, muscular force). The training protocol consisted of two training sessions per week performed in our institute, 90 min for each (warm-up, aerobic phase, strength phase and stretching) and one or more at home autonomously. Results: The cardiopulmonary testing after the training period documents a significant improvement in V ̇O2peak (15 ± 4 mL/kg/min vs. 17 ± 4; p = 0.001) and in work load (87 ± 30 watts vs. 108 ± 37; p = 0.001). Additionally, strength capacity significantly increased after the cardiac rehabilitation program, (quadriceps: 21 ± 18 kg vs. 29 ± 16 kg, p = 0.00003). Flexibility tests show a positive trend, but without statistical significance (sit-and-reach test: -19 ± 11 cm vs. -15 ± 11.7 cm; back-scratch test: -19 ± 11.6 cm vs. -15 ± 10 cm; lateral flexibility right -44 ± 1.4 cm vs. -43 ± 9.5 cm; left -43 ± 5 vs. -45 ± 8.7 cm). Conclusion: A brief period of combined aerobic, strength and flexibility exercise training (FIDE project) proved to be effective and safe in improving functional capacity in patients with cardiac implantable devices.

Systematic Cardiovascular Screening in Olympic Athletes before and after SARS-CoV-2 Infection.

Conflicting results on the cardiovascular involvement after SARS-CoV-2 infection generated concerns on the safety of return-to-play (RTP) in athletes. The aim of this study was to evaluate the prevalence of cardiac involvement after COVID-19 in Olympic athletes, who had previously been screened in our pre-participation program. Since November 2020, all consecutive Olympic athletes presented to our Institute after COVID-19 prior to RTP were enrolled. The protocol was dictated by the Italian governing bodies and comprised: 12-lead ECG, blood test, cardiopulmonary exercise test (CPET), 24-h ECG monitoring, and spirometry. Cardiovascular Magnetic Resonance (CMR) was also performed. All Athletes were previously screened in our Institute as part of their periodical pre-participation evaluation. Forty-seven Italian Olympic athletes were enrolled: 83% asymptomatic, 13% mildly asymptomatic, and 4% had pneumonia. Uncommon premature ventricular contractions (PVCs) were found in 13% athletes; however, only 6% (n = 3) were newly detected. All newly diagnosed uncommon PVCs were detected by CPET. One of these three athletes had evidence for acute myocarditis by CMR, along with Troponin raise; another had pericardial effusion. No one of the remaining athletes had abnormalities detected by CMR. Cardiac abnormalities in Olympic athletes screened after COVID-19 resolution were detected in a minority, and were associated with new ventricular arrhythmias. Only one had evidence for acute myocarditis (in the presence of symptoms and elevated biomarkers). Our data support the efficacy of the clinical assessment including exercise-ECG to raise suspicion for cardiovascular abnormalities after COVID-19. Instead, the routine use of CMR as a screening tool appears unjustified.

Left ventricular systolic performance is improved in elite athletes.

AIMS: We sought to investigate the systolic time interval (STI) and efficiency of left ventricular (LV) contraction comparatively in elite athletes and healthy sedentary controls by means of three-dimensional echocardiography (3DE). METHODS AND RESULTS: Four hundred and twenty-nine elite athletes, involved in skill (n = 41), power (n = 63), mixed (n = 167), and endurance (n = 158) disciplines and 98 sedentary controls, matched for age, underwent 3DE. By off-line analysis, we measured the absolute and relative (normalized by the R-R interval) timing of LV systolic emptying (STI and STI%) and the systolic flow velocity (SFV = stroke volume/STI). Both STI and STI% were shorter in athletes, regardless of the sport discipline, compared with controls (respectively, 324 ± 36 vs. 345 ± 33 ms, P < 0.001; 30 ± 4 vs. 40 ± 4%; P< 0.001). Regression analysis showed that heart rate was the most important determinant of STI (R(2) = 0.38; P < 0.001), while age, body surface area, blood pressure, LV volumes, and mass had no significant association. After removing the effects of heart rate and gender, athletes showed a significant reduction (by 50.4 ms; 95% confidence interval, from 57.7 to 43.1) in STI compared with untrained subjects. Finally, higher SFV were identified in skill (256 ± 60 mL/s; P < 0.001), strength (297 ± 78 mL/s; P < 0.001), mixed (308 ± 67 mL/s; P < 0.001), and endurance (334 ± 74 mL/s; P < 0.001) athletes compared with controls (204 ± 50 mL/s). CONCLUSION: Elite athletes show a significant shortening of the systolic time duration in comparison with sedentary controls, in association with a significant increase in LV emptying velocity. This pattern characterizes the physiological LV adaptation of the athletes and may potentially be useful in differential diagnosis of the 'athlete heart'.

The role of cardiovascular magnetic resonance in the screening before the return-to-play of elite athletes after COVID-19: utility o futility?

Recent reports based on cardiovascular magnetic resonance (CMR) showed a wide range of prevalence of inflammatory heart diseases in COVID-19 convalescent athletes ranging from 0.4 up to 15%. These observations had an important impact in the field of sport cardiology opening an intense debate around the best possible screening strategy before the return-to-play. The diagnostic yield of CMR for detecting acute inflammatory disease is undebatable. However, the opportunity to use it in the screening protocol after COVID-19 has been questioned. Current evidence does not seem to support the routine use of CMR and the prescription of CMR should be based upon clinical indication.

Female Athlete's Heart: Sex Effects on Electrical and Structural Remodeling.

BACKGROUND: Most of our knowledge on training-induced cardiac remodeling is derived from men, with the paucity of data from women representing an important gap in knowledge. The aim of the study was to define the electrocardiographic and morphological features of female athlete's heart, with special attention to differences related to sex and sport. METHODS: Seven hundred twenty Olympic athletes (360 females and 360 age- and sport-matched males, mean age: 23±5 years) were evaluated by clinical, resting, and exercise electrocardiography and echocardiography. RESULTS: Anterior T-wave inversion was more common in females than males (P<0.05). Left ventricular (LV) wall thickness and LV mass were greater in men (P<0.001). Females had smaller absolute but greater indexed LV and right ventricular (RV) dimensions as compared to males. Most women had normal LV geometry (80.8%). A progressive increase in LV/RV dimensions was observed in women from those engaged in skill, power, to mixed and endurance disciplines, with the endurance ones demonstrating the greatest degree of RV dilatation. Women had a peculiar biventricular adaptation, with higher LV/RV (1.41±0.16 versus 1.36±0.15, P<0.0001) and lower RV inflow/outflow ratio (P<0.001), as compared to men. CONCLUSIONS: Sex significantly affects cardiac remodeling in athletes, with females presenting a different electrical and structural remodeling. Women maintain a normal LV geometry, with relative larger increase of cavity dimensions compared with men. Type of sport has a relevant impact, with endurance athletes exhibiting the greatest degree of RV and LV dimensional remodeling. The present study confirms the need for a sex-based approach for interpreting the complex features of athlete's heart in women.

Cardiovascular Risk Factors and Haematological Indexes of Inflammation in Paralympic Athletes with Different Motor Impairments.

Haematological indexes of both inflammation and platelet activation have been suggested as predictive markers of cardiovascular disease (CVD), which has high prevalence in Paralympic athletes (PA). Different mechanisms could play a role in increasing CVD risk in PA with spinal cord injury (PA-SCI), lower limb amputation (PA-LLA), or upper limb impairment (PA-ULI). We compared, in 4 groups of PA competing in power, intermittent (mixed metabolism), and endurance sports, Framingham Risk Score (FRS), metabolic syndrome criteria (MetS-C), inflammation (INFLA) Score, 5 haematological indexes of platelet activation (mean platelet volume (MPV), platelet distribution width (PDW), and the ratios between MPV and platelet (MPVPR), between MPV and lymphocyte (MPVLR), and between PDW and lymphocyte (PDWLR)) and the endogenous antioxidants uric acid (UA) and bilirubin (BR). A retrospective chart review of PA from preparticipation examinations' records (London 2012 and Sochi 2014 Paralympics) was performed. We included 25 PA-SCI (13 with high and 12 with low lesion, PA-SCI-H and PA-SCI-L), 15 PA-LLA, and 10 PA-ULI. FRS and INFLA Score did not differ among groups, but PA-SCI-H had lower HDL, compared to PA-SCI-L and PA-ULI. PA-LLA had more MetS diagnostic criteria with significant higher glucose levels than other groups. PA-SCI-H had significantly lower lymphocytes' count compared to PA-LLA and higher MPV, PDW, MPVPR, MPVLR, and PDWLR. SCI-H had lower BR, haemoglobin, haematocrit, proteins, and creatinine. No interaction was found between the 3 kinds of sitting sports and the 2 groups of health conditions (PA-SCI and PA-LLA). In conclusion, PA-LLA had a higher cardiometabolic risk, whereas PA-SCI-H had a higher platelet-derived cardiovascular risk. Further larger studies are needed to investigate the relationship between indexes of inflammation/oxidation and dietary habit, body composition, and physical fitness/performance in PA with motor impairments.

Relation between training-induced left ventricular hypertrophy and risk for ventricular tachyarrhythmias in elite athletes.

The aim of this study was to analyze the relation between the magnitude of training-induced left ventricular (LV) hypertrophy and the frequency and complexity of ventricular tachyarrhythmias in a large population of elite athletes without cardiovascular abnormalities. Ventricular tachyarrhythmias are a common finding in athletes, but it is unresolved as to whether the presence or magnitude of LV hypertrophy is a determinant of these arrhythmias in athletes without cardiovascular abnormalities. From 738 athletes examined at a national center for the evaluation of elite Italian athletes, 175 consecutive elite athletes with 24-hour ambulatory (Holter) electrocardiographic recordings (but without cardiovascular abnormalities and symptoms) were selected for the study group. Echocardiographic studies were performed during periods of peak training. Athletes were arbitrarily divided into 4 groups according to the frequency and complexity of ventricular arrhythmias during Holter electrocardiographic monitoring. No statistically significant relation was evident between LV mass (or mass index) and the grade or frequency of ventricular tachyarrhythmias. In addition, a trend was noted in those athletes with the most frequent and complex ventricular ectopy toward lower calculated LV mass. In conclusion, ventricular ectopy in elite athletes is not directly related to the magnitude of physiologic LV hypertrophy. These data offer a measure of clinical reassurance regarding the benign nature of ventricular tachyarrhythmias in elite athletes and the expression of athlete's heart.

Three-dimensional echocardiographic characterization of left ventricular remodeling in Olympic athletes.

The aim of the present study was to assess, using 3-dimensioanl echocardiography, the morphologic characteristics, determinants, and physiologic limits of left ventricular (LV) remodeling in 511 Olympic athletes (categorized in skill, power, mixed, and endurance sport disciplines) and 159 sedentary controls matched for age and gender. All subjects underwent 3-dimensional echocardiography for the assessment of LV volumes, ejection fraction, mass, remodeling index (LV mass/LV end-diastolic volume), and systolic dyssynchrony index (obtained by the dispersion of the time to minimum systolic volume in 16 segments). Athletes had higher LV end-diastolic volumes (157 ± 35 vs 111 ± 26 ml, p <0.001) and mass (156 ± 38 vs 111 ± 25 g, p <0.001) compared to controls. Body surface area and age had significant associations with LV end-diastolic volume (R(2) = 0.49, p <0.001) and mass (R(2) = 0.51, p <0.001). Covariance analysis showed that also gender and type of sport were significant determinants of LV remodeling; in particular, the highest impact on LV end-diastolic volume and mass was associated with male gender and endurance disciplines (p <0.001). Regardless of the type of sport, athletes had similar LV remodeling indexes to controls (1.00 ± 0.06 vs 1.01 ± 0.07 g/mL, p = 0.410). No differences were found between athletes and controls for the ejection fraction (62 ± 5% and 62 ± 5%, p = 0.746) and systolic dyssynchrony index (1.06 ± 0.40% and 1.37 ± 0.41%, p = 0.058). In conclusion, 3-dimensional echocardiographic morphologic and functional assessment of the left ventricle in Olympic athletes demonstrated a balanced adaptation of LV volume and mass, with preserved systolic function, regardless of specific disciplines participated.

Patterns of ventricular tachyarrhythmias associated with training, deconditioning and retraining in elite athletes without cardiovascular abnormalities.

Ventricular tachyarrhythmias commonly occur in trained athletes during ambulatory Holter electrocardiography and are usually associated with a benign course. Such arrhythmias have been demonstrated to be sensitive to short periods of athletic deconditioning; however, their response to retraining is not known. Twenty-four hour Holter electrocardiographic monitoring was performed at peak training and after 3 to 6 months of deconditioning and was repeated in the present study after 2, 6, and 12 months of retraining in 37 athletes with frequent and complex ventricular tachyarrhythmias and without cardiovascular abnormalities. These subjects showed partial (101 to 500 ventricular premature complexes [VPCs]/24 hours) or marked (<100 VPCs) reversibility of arrhythmias after deconditioning. Retraining initially resulted in a significant increase in arrhythmia frequency compared with deconditioning (from 280 ± 475 to 1,542 ± 2,186 VPCs; p = 0.005), couplets (0.14 ± 0.42 to 4.4 ± 8.2; p = 0.005), and nonsustained ventricular tachycardia (from 0 to 0.8 ± 1.8; p = 0.02). Subsequently, a progressive reduction was seen in the frequency of all ventricular arrhythmias during the 1 year of training to well below that at the peak training levels (VPCs 917 ± 1,630, couplets 1.8 ± 4.2, and nonsustained ventricular tachycardia 0.4 ± 1.2). Such annual arrhythmia reduction was significantly greater statistically in those athletes with marked reversibility after deconditioning than in the athletes with partial reversibility (69 ± 139 vs 1,496 ± 1,917 VPCs/24 hours, respectively; p = 0.007). No cardiac events or symptoms occurred during 1 year of follow-up. In conclusion, in elite athletes without cardiovascular disease, a resumption in intense training after deconditioning was associated with variable, but prolonged, suppression of ventricular ectopy. The absence of adverse clinical events or symptoms associated with the resumption of training supports the continued eligibility in competitive sports for such athletes and is also consistent with the benign nature of physiologic athlete's heart syndrome.

Field evaluation of paralympic athletes in selected sports: implications for training.

PURPOSE: The purpose of this study was 1) to describe the acute cardiorespiratory and metabolic responses of Paralympic athletes participating in the following five sports: Nordic sit skiing (NS, n = 5), wheelchair distance racing (WR, n = 6), wheelchair basketball (WB, n = 13), wheelchair fencing (WF, n = 6), and wheelchair tennis (WT, n = 4); and 2) to examine the relationship between field test performance and laboratory measures of aerobic fitness of these Paralympic athletes. METHODS: Each athlete completed an incremental arm cranking exercise test to determine ventilatory threshold (VT) and peak oxygen uptake (VO2peak). Subsequently, field assessments were carried out using a telemetric system to measure the cardiorespiratory responses in their respective sport. RESULTS: VT and VO2peak (both expressed in milliliters per kilogram per minute) of athletes competing in NS (38.3 +/- 5.76 and 51.0 +/- 6.92 mL x kg(-1) x min(-1)) and WR (35.5 +/- 5.96 and 48.1 +/- 6.35 mL x kg(-1) x min(-1)) were significantly higher (P < 0.05) than those competing in WB (26.0 +/- 2.13 and 36.9 +/- 3.70 mL x kg(-1) x min(-1)), WF (23.2 +/- 3.96 and 34.4 +/- 5.81 mL x kg(-1) x min(-1)), and WT (24.0 +/- 2.30 and 33.1 +/- 2.85 mL x kg(-1) x min(-1)). In the field tests, the average V O2, higher in NS and WR than in WB, WF, and WT, during NS, WR, WB, WF, and WT was 79.4% +/- 3.30%, 84.4% +/- 2.10%, 72.1% +/- 5.72%, 73.0% +/- 3.10%, and 73.0% +/- 1.91%, respectively, of VO2peak. There was a strong linear relationship between VO2 measured during the field tests and VT and VO2peak (R2 = 0.92 in each case). CONCLUSIONS: Athletes regulated their average work intensity during the field tests in the five Paralympic sports to approximate their individualized VT measured during incremental arm cranking exercise test, and this intensity was within the range recommended by the American College of Sports Medicine to improve cardiorespiratory fitness in well-trained subjects. In addition, performance of Paralympic athletes in these sports was highly dependent upon athletes' aerobic fitness.

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.