Exercise-Induced Cardiac Remodeling
Section snippets
Overview of relevant exercise physiology
All forms of exercise require an increase in skeletal muscle work. There is a direct relationship between exercise intensity (external work) and the body's demand for oxygen. The oxygen demand during exercise is met by increasing pulmonary oxygen uptake (Vo2). In addition, the cardiovascular system is responsible for transporting oxygen-rich blood from the lungs to the skeletal muscles, a process quantified as cardiac output (in liters per minute). Exercise-induced cardiac remodeling enhances
Determinants of EICR magnitude
The extent of EICR varies considerably across individual athletes. Obvious explanatory factors including sport-type, prior exercise exposure, and training-intensity/duration do not explain all of this variability.47 Additional factors including sex, ethnicity, and genetics are contributory. Available data suggest that female athletes exhibit quantitatively less physiologic remodeling than their male counterparts.44, 48, 49, 50, 51, 52, 53 This appears to be true even when cardiac dimensions are
Cellular mechanisms of EICR
The cellular pathways responsible for EICR remain poorly understood. There are currently no mechanistic studies in humans that explain why the myocardial cells remodel in the face of repeated exercise bouts. The lack of in vivo data relates to the numerous challenges, most notably, the acquisition of cardiac tissue from healthy subjects, inherent in study design. However, animal data examining pathologic forms of ventricular hypertrophy during experimental exercise intervention may be
EICR: adaptive physiology vs pathologic myopathy
The significance of cardiac enlargement in athletes has been debated since the time of its initial description. Although EICR is most often regarded as a beneficial adaptation to exercise, this view has not been universally accepted. It was postulated as early as 1902 that cardiac enlargement in athletes is a form of overuse pathology and that prolonged participation in sport could lead to premature cardiovascular system collapse.63 This concept has resurfaced numerous times over the last
Conclusions
Participation in vigorous recreational exercise and competitive athletics continues to gain popularity worldwide because of factors including the documented health benefits of regular physical exercise, increasing availability of community-based athletic programs, and growing numbers of open-enrollment sport events (ie, community-based road running races). This increasing sport participation will be paralleled by increases in the number of people with features of EICR. The practicing
Statement of Conflict of Interest
The authors declare that there are no conflicts of interest.
References (72)
- et al.
Introduction: eligibility recommendations for competitive athletes with cardiovascular abnormalities—general considerations
J Am Coll Cardiol
(2005) - et al.
Physiologic limits of left ventricular hypertrophy in elite junior athletes: relevance to differential diagnosis of athlete's heart and hypertrophic cardiomyopathy
J Am Coll Cardiol
(2002) - et al.
Effect of intensive resistance training on isotonic exercise Doppler indexes of left ventricular systolic function
Am J Cardiol
(2002) - et al.
Left ventricular structure and function by echocardiography in ultraendurance athletes
Am J Cardiol
(1986) - et al.
Echocardiographic study of cardiac dimensions and function in the endurance-trained athlete
Am J Cardiol
(1977) - et al.
Serial left ventricular adaptations in world-class professional cyclists: implications for disease screening and follow-up
J Am Coll Cardiol
(2004) - et al.
An ultrasound speckle tracking (two-dimensional strain) analysis of myocardial deformation in professional soccer players compared with healthy subjects and hypertrophic cardiomyopathy
Am J Cardiol
(2007) - et al.
Doppler tissue imaging: regional myocardial function in hypertrophic cardiomyopathy and in athlete's heart
J Am Soc Echocardiogr
(2003) - et al.
The impact of endurance exercise training on left ventricular torsion
JACC Cardiovasc Imaging
(2010) - et al.
Pulsed Doppler tissue imaging in endurance athletes: relation between left ventricular preload and myocardial regional diastolic function
Am J Cardiol
(2000)
The effects of aging and physical activity on Doppler measures of diastolic function
Am J Cardiol
Left ventricular myocardial velocities and deformation indexes in top-level athletes
J Am Soc Echocardiogr
Symmetric cardiac enlargement in highly trained endurance athletes: a two-dimensional echocardiographic study
Am Heart J
Athlete's heart: right and left ventricular mass and function in male endurance athletes and untrained individuals determined by magnetic resonance imaging
J Am Coll Cardiol
Significance of electrocardiographic right bundle branch block in trained athletes
Am J Cardiol
Cardiac magnetic resonance assessment of left and right ventricular morphologic and functional adaptations in professional soccer players
Am Heart J
Prevalence and clinical significance of left atrial remodeling in competitive athletes
J Am Coll Cardiol
Left atrial volume index in highly trained athletes
Am Heart J
Atrial remodeling, autonomic tone, and lifetime training hours in nonelite athletes
Am J Cardiol
Influence of sex on the “Athlete's Heart” in trained cyclists
J Sci Med Sport
Ethnic differences in left ventricular remodeling in highly-trained athletes relevance to differentiating physiologic left ventricular hypertrophy from hypertrophic cardiomyopathy
J Am Coll Cardiol
Angiotensinogen gene M235T polymorphism predicts left ventricular hypertrophy in endurance athletes
J Am Coll Cardiol
Impact of family hypertension history on exercise-induced cardiac remodeling
Am J Cardiol
Exercise-induced right ventricular dysplasia/cardiomyopathy–an emerging condition distinct from arrhythmogenic right ventricular dysplasia/cardiomyopathy
Heart Lung Circ
Long-term clinical consequences of intense, uninterrupted endurance training in olympic athletes
J Am Coll Cardiol
Skidlauf und Skidwettlauf. Eine medizinische Sportstudie
Mitt Med Klin Upsala
The effects of training. A study of the Harvard University crews
Boston Med Surg J
Relations between heart size and physical efficiency in male and female athletes in comparison with normal male and female subjects
Arch Kreislaufforsch
The heart and blood circulation in athletes
Med Welt
Roentgenological and instrumental examination of the heart in athletes
Klin Med
Human circulation: regulation during physical stress
The normal range and determinants of the intrinsic heart rate in man
Cardiovasc Res
Exhaustive endurance training for 6-9 weeks did not induce changes in intrinsic heart rate and cardiac autonomic modulation in female athletes
Int J Sports Med
Noninvasive evaluation of ventricular hypertrophy in professional athletes
Circulation
Physiologic left ventricular cavity dilatation in elite athletes
Ann Intern Med
The upper limit of physiologic cardiac hypertrophy in highly trained elite athletes
N Engl J Med
Cited by (116)
Sex-specific cytotoxicity of ostarine in cardiomyocytes
2023, Molecular and Cellular EndocrinologyAortic root/left ventricular diameters golden ratio in competitive athletes
2023, International Journal of CardiologyCardiac
2023, The Youth Athlete: A Practitioner's Guide to Providing Comprehensive Sports Medicine CareExercise-derived peptide protects against pathological cardiac remodeling
2022, eBioMedicineCitation Excerpt :The positive effects of physical exercise in suppressing cardiac hypertrophy and improving cardiac function have been documented in patients with heart failure.10,11 Exercise could directly trigger intrinsic myocardial changes, including increased cytosolic antioxidant capacity, mitochondrial biogenesis, and cardioprotective cardiac growth, by activating signaling pathways, such as insulin-like growth factor 1/ Phosphatidylinositol 3-kinase/protein kinase B (IGF1/PI3K/Akt) pathway,12,13 and modulating gene expression via microRNAs (miR-17-3p, miR-222, etc.),14–17 which promote physiological cardiac remodeling and resist pathological remodeling.18–20 Exercise also orchestrates multisystemic effects, such as cardiovascular adaptions, by provoking the muscle and other tissues to exert endocrine effects and release various signaling molecules named “exerkines” into the circulation.21–23
Differentiating Physiology from Pathology: The Gray Zones of the Athlete's Heart
2022, Clinics in Sports Medicine
Statement of Conflict of Interest. See page 384.