The athlete's heart Part I (Review)

Area of Science:

• Cardiovascular Physiology
• Sports Medicine
• Exercise Science

Background:

• Sedentary lifestyles pose significant cardiovascular risks.
• Athlete's heart characteristics are key determinants of endurance performance.
• Cardiac disorders are frequently linked to sudden cardiac death in athletes.

Purpose of the Study:

• To outline the key morphologic, functional, and regulatory adaptations of the athlete's heart.
• To highlight the physiological significance of these cardiac changes in athletes.
• To differentiate the athlete's heart from pathological cardiac conditions.

Main Methods:

• Review of existing literature on cardiac adaptations in athletes.
• Analysis of morphologic changes, including left ventricular hypertrophy and coronary vascularization.
• Evaluation of functional parameters such as cardiac output, diastolic function, and heart rate variability.
• Assessment of metabolic and electrical modifications within the cardiac system.

Main Results:

• Physiologic left ventricular (LV) hypertrophy and an enhanced coronary capillary network are primary morphologic adaptations.
• Functional adaptations include improved systolic and diastolic function, altered cardiac metabolism, and modified electrical properties.
• The most readily observable functional change is enhanced LV diastolic function.
• Regulatory adaptations are primarily characterized by a reduced resting heart rate (HR).

Conclusions:

• The athlete's heart is a normal, enlarged heart resulting from physiological adaptation to training.
• Key features include a lower resting heart rate, increased cardiac output, and superior oxygen delivery capacity to skeletal muscles.
• These adaptations are essential for optimizing endurance performance and maintaining cardiovascular health in athletes.