Myocardial adaptation and efficiency in response to intensive physical training in elite speedskaters
Introduction
Characteristic changes of the athlete's heart include increased chamber dimensions, increased left ventricular mass, right ventricular dilatation, reduced resting right ventricular systolic function and enhanced diastolic function [1]. These features are thought to represent the physiological adaptations that occur as a result of repetitive, intense physical training [2], [3], [4], [5]. This constellation of findings in athletes can appear very similar to either hypertrophic cardiomyopathy or arrhythmogenic right ventricular dysplasia, both of which have been linked to increased risk of sudden death in athletes, therefore the ability to differentiate from these two entities is of great importance [6], [7], [8], [9]. Thus, there have been studies to differentiate between these conditions (physiological versus pathological states), though there remained some overlap using conventional parameters.
Over the last few decades, there has been vast amount of interest arising from various non-invasive studies describing the cardiac remodeling associated with different forms of exercise [10], [11] Despite this, limited information is available on highly elite athletes using novel echocardiographic assessment such as tissue Doppler imaging [12]. The evaluation of right ventricular adaptive structural and funcional changes in athletes is also lacking.
We aimed to better define anatomic and physiologic cardiac adaptations to exercise in young, highly competitive athletes whose exercise regimens include both intense aerobic and weight training. In order to increase our likelihood of identifying cardiac changes associated with training, we chose to study Olympic elite athletes training for the 2006 Winter Games. At the same time, since cardiac adaptation may be sports-specific [13], we selected speedskaters due to their intense training regimen which incorporates components of aerobic and strength or weight training. These athletes have also not been studied as extensively as other groups of athletes and their unique physiologic adaptations could possibly provide new insight. Competitive speedskating is one of the most demanding sports, as it is considered the fastest race performed by humans without the aid of a machine or relying on the surface upon which the action occurs [14]. This requires the highest components of both static and dynamic physical demands [13], [15].
Section snippets
Study population
The subjects consisted of 24 athletes (16 males and 8 females; 9 Americans, 5 Italians and 10 Chinese; aged 22 ± 3 years) and 15 sedentary young subjects (24 ± 3 years; 7 males and 8 females). All of the athletes trained intensively in preparation for the Olympic competition and performed cross-training in both sprint and endurance aerobic and strength training exercises. The sedentary subjects exercised less than 3 times a week with less than 1 h of exertion each time for at least 6 months
Baseline clinical and conventional echocardiographic parameters
The baseline characteristics of the 2 groups were similar with respect to their age, gender, body size, heart rate and blood pressures (Table 1). The left atrium was significantly larger in the athletes (3.4 ± 0.3 vs 3.0 ± 0.3 cm; 18.9 ± 2.7 vs 12.3 ± 2.0 cm2 and 33 ± 7 vs 18 ± 5 ml/m2; all P < 0.001 for anterior–posterior diameter, area and indexed volume at LV end-systole respectively). Similarly, but to a lesser extent, the LV end-diastolic and end-systolic volumes were greater in the athletes (Table 1).
Discussion
These athletes exhibit potentially important features of cardiac adaptation to regular intense physical exertion. Baseline imaging revealed that compared to similarly aged, sedentary subjects, the athletes exhibit evidence of chamber dilatation without hypertrophy. Augmented diastolic function of both the left and right ventricles as evidenced by higher tissue Doppler velocities at baseline.
Some features of classic ‘athlete's heart’ including left ventricular hypertrophy and marked left
Acknowledgements
We would like to acknowledge GE Healthcare for their equipment loan and technical support. K.K.P. is funded by the National University Hospital, National Healthcare Group, Singapore and a fellowship award from the National Medical Research Council, Singapore.
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Role of Doppler Diastolic Parameters in Differentiating Physiological Left Ventricular Hypertrophy from Hypertrophic Cardiomyopathy
2018, Journal of the American Society of EchocardiographyCitation Excerpt :We did not compare our cohort with a control population, but we found similar results in our athletes, who had an average E/A ratio of 2.1 ± 0.7, and almost 50% showed transmitral E/A ratios > 2. Previous studies evaluating septal and lateral wall motion in athletes have also shown increased peak early (E′) or reduced A′ tissue velocities compared with control subjects.18,22,23 Training previously sedentary individuals has demonstrated an improvement in diastolic function using DTI indices.6
Atrial Enlargement in the Athlete's Heart: Assessment of Atrial Function May Help Distinguish Adaptive from Pathologic Remodeling
2018, Journal of the American Society of EchocardiographyCitation Excerpt :Furthermore, few and conflicting data have been collected with the application of this technique in athlete's heart. Indeed, whereas some authors demonstrated a similar pattern of PV flow between athletes and control subjects,40,41 others observed an enhancement of conduit function in athletes assessed by PV early diastolic wave.42 Accordingly, this method is currently not routinely applied.
Normative Reference Values of Right Heart in Competitive Athletes: A Systematic Review and Meta-Analysis
2017, Journal of the American Society of EchocardiographyCitation Excerpt :Of these, 315 were excluded for various reasons, most commonly because the RV was not evaluated. Thus, 46 studies2-8,20-58 met the inclusion criteria for the analysis, and a final population of 6,806 athletes were included in the present meta-analysis. We also identified 84 articles for review of CMR studies (Figure 2).
Left Atrium Size in Elite Athletes
2015, JACC: Cardiovascular ImagingCitation Excerpt :Our search of the literature identified 1,546 nonduplicate citations (Figure 1). Of these, 54 studies (7–60) met the inclusion criteria for this analysis. Forty-eight of the 54 included studies reported absolute LA diameter in 2,626 endurance-trained athletes; 411 strength-trained athletes; 875 combined endurance- and strength-trained athletes; 3,106 athletes for whom pure exercise classification was not possible, which we labeled “mixed trained athletes”; and 1,044 controls (Table 1).
Utility of strain echocardiography at rest and after stress testing in arrhythmogenic right ventricular dysplasia
2013, American Journal of CardiologyThe right ventricle of the elite high end endurance athlete cannot be underestimated
2012, Journal of the American Society of Echocardiography