Guide: Athletic Heart Syndrome

The resting heart rate is the heart pumping the lowest amount of blood you need when not exercising. If you’re sitting or lying and calm, relaxed and aren’t ill, your heart rate is normally between 60 and 100 beats per minute. Active people often have a lower resting heart rate (as low as 40) because their heart muscles are in better condition and don’t need to work as hard to maintain a steady beat
The heart rate for athletes vs non-athletes differs as the amount of intense physical training they undergo is different. A young, strong, healthy athlete may have a resting heart rate of 30-40 beats per minute, but may easily increase his heart rate to 180 beats per minute with exercise. A heart rate monitor can keep track during exercise.

Athletes tend to have lower resting heart rates because training builds speed, fitness, muscle and endurance and also trains your heart muscles to pump a higher volume of blood with each heartbeat.  So, maximal stroke volume and cardiac output increase, contributing to a lower resting heart rate and longer diastolic filling time. 
Athlete resting heart rate is lower and is generally considered a normal and healthy adaptation to training. Conditioned athletes and other highly fit individuals might have normal resting heart rates of 40 to 60 beats per minute. Factors such as genetics, age, and the type of training can influence the extent of these adaptations.
 

Sudden cardiac death (SCD) is the most frequent medical cause of sudden death in athletes. A recent estimate of SCD incidence ranged from 1 in 40,000 to 1 in 80,000 athletes per year.
In older athletes, SCD is primarily due to CAD and associated complications. In younger athletes, it is due to congenital or genetically mediated cardiovascular disease, such as Hypertrophic cardiomyopathy (HCM), coronary artery anomalies, cardiomyopathies, or primary arrhythmogenic disorders.
Approximately 30% of athletes with SCD have been reported to have had symptoms such as chest pain, shortness of breath, performance decline, palpitations, pre-syncope, or syncope leading up to the event.
 

Although there are similarities in the signs for both athletes' heart and hypertrophic cardiomyopathy(HCM), they are completely different conditions. Here are some pointers by the American Heart Association to check an athlete’s heart Vs HCM: 
Hypertrophic cardiomyopathy is most often caused by abnormal genes in the heart muscle, which causes the walls of the heart chamber (left ventricle) to become thicker than normal. The thickened walls may become stiff and reduce the amount of blood taken in and pumped out to the body with each heartbeat.
HCM is a chronic disease that can get worse over time.
People with HCM should limit their activity to adjust for their disease.  
People with HCM are at higher risk for developing atrial fibrillation, which can lead to blood clots, stroke and heart failure. It can also lead to sudden cardiac arrest, but this is rare.
Athletic heart syndrome does not pose any such condition, is not fatal and is reversible with detraining.
 

There are no specific dietary recommendations for Athletic heart syndrome. However, the American Heart Association recommends certain dietary patterns for improved heart health: 
Eat an overall healthy dietary pattern that emphasizes: 
A wide variety of fruits and vegetables.
Whole grains and products made up mostly of whole grains.
Healthy sources of protein (mostly plants such as legumes and nuts; low-fat or nonfat dairy).
Liquid non-tropical vegetable oils.
Minimally processed foods.
Minimized intake of added sugars.
Foods prepared with little or no salt.
Limited or preferably no alcohol intake.