“In highly conditioned athletes, a big heart-the literal, not the metaphorical kind- is a sign of health and power. But in some cases, it can be a deadly burden.”

Elite athletes often have enlarged hearts. This enables them to reach amazing levels of athletic endurance and strength. These super hearts can pump huge amounts of blood which carries oxygen to the muscles. A super charged heart is the same as a super charged motor in a car.
This condition is developed as result of intense cardio and/or strength training.

The athlete’s heart condition is most common in extreme swimmers, cyclists, runners, rowers and weight lifters.
Unfortunately, the extreme training of these athletes can sometimes reveal, or make worse, serious pre-existing problems with their hearts. This has led to the premature deaths of some very prominent athletes.

The heart will grow larger with an increased work load, resulting in a larger heart and/or a thicker heart. Both of these will bring about the athlete’s heart condition.
There are two basic ways to increase blood supply to exercising muscles: Make the heart beat faster or pump a larger volume of blood with each beat. This creates less wear on the heart. Thus the size of the heart, not the maximum beats, increases with conditioning.
Example: a world class marathoner could have the same maximum heart rate as an average person, the difference being the marathoner’s heart pumps more blood with each beat.

Oxygen depleted blood returns from the body and enters the right side of the heart. Then, blood is pumped out of the right ventricle to the lungs, where it picks up new oxygen before returning to the left side or left ventricle. Finally, the fresh oxygenated blood is pumped back into the body by the left ventricle..

The size of the left ventricle when fully expanded, the thickness of its walls, and the amount of blood it pumps with each beat, (called stroke volume) are all key stats in assessing the heart. A technique using ultra sound technology called echocardiography allows doctors to watch the heart in action, freeze the image, and then take measurements to establish the athlete’s heart.

Elite athletes had a 46% larger left ventricle than non-conditioned people.
They also had a 33%increase in stroke volume. Resting heart rates of low 30’s for marathoners due to enormous stroke volume. A normal person would pass out if his heart rate dropped to 30.

A fascinating aspect of the athlete’s heart is how fast the condition comes and goes. It can develop in weeks and vanish just as fast. Ten endurance runners from New
Mexico returned to college with normal sized hearts after a summer of reduced training. In just 4 months of rigorous training, their left ventricles increased 23%.

How different types of exercises influence growth of an athletes heart
The exact load on a heart determines specific changes.
Volume loading, caused by intense aerobic training.
Here, muscles demand oxygen for a longer time.
Volume loading increases the left ventricle, thus increasing the stroke volume.
Examples: running swimming, biking
Pressure loading, caused by intense anaerobic strength training. Increases thickness of right wall.
Example:weight training. Thus, cross training gives us the most versatile conditioned athletes.

Some elite athletes may have been born with heart conditions which they never noticed. Since their hearts were so big, they resembled the athlete’s heart condition, not the enlarged diseased heart they were born with. Another reason why these athletes don’t know they have diseased hearts is that their enlarged hearts masked and compensated for their genetic defects. If detected early, many deaths could have been avoided with the use of proper medication.

Viral Cardiomyopathy
Virus attacks left ventricle. Can be cured.
Hypertrophic Cardiomyopathy(HCM)
Abnormal thickening of the left ventricle. Most common disease.
Difficult to detect since it resembles the athlete’s heart. HCM is genetic and has no prior symptoms. 1 in 500 persons has this condition.

Congenital abnormalities : Structural problems from birth.
Coronary artery disease (CAD):
Arteries are blocked: Sergei Grinkov died. Never knew he had a problem.
Morfans Syndrome : disorder of heart’s connective tissue. Flo Hyman died. Did not have a clue about this.
Myocarditis : Inflammation due to viral infection. Hank Gathers sought treatment, but still died.

Early in the twentieth century, there was a debate about the long term effects of the athlete’s heart. After years of testing and research, the result is that there are no dangerous consequences so long as there are no hidden diseases.
The sudden death of some elite athletes was sensational and unnerving. However, these deaths were not due to over training , but rather a predisposed heart problem masked by an extraordinary conditioned heart.

Some notable athletes who died early due to undetected heart disease
Paavo Nurmi- great marathoner/Olympian
Babe Didrickson- Words greatest woman athlete
Bill Rogers- Ultra Marathoner
Secretariat- Triple Crown winner

Paavo Nurmi &Bill Rogers

Babe Didrickson

Secretariat