<P> The largest part of the heart is usually slightly offset to the left side of the chest ( though occasionally it may be offset to the right ) and is felt to be on the left because the left heart is stronger and larger , since it pumps to all body parts . Because the heart is between the lungs , the left lung is smaller than the right lung and has a cardiac notch in its border to accommodate the heart . The heart is cone - shaped , with its base positioned upwards and tapering down to the apex . An adult heart has a mass of 250 -- 350 grams ( 9 -- 12 oz ) . The heart is typically the size of a fist : 12 cm ( 5 in ) in length , 8 cm ( 3.5 in ) wide , and 6 cm ( 2.5 in ) in thickness . Well - trained athletes can have much larger hearts due to the effects of exercise on the heart muscle , similar to the response of skeletal muscle . </P>
<P> The largest part of the heart is usually slightly offset to the left side of the chest ( though occasionally it may be offset to the right ) and is felt to be on the left because the left heart is stronger and larger , since it pumps to all body parts . Because the heart is between the lungs , the left lung is smaller than the right lung and has a cardiac notch in its border to accommodate the heart . The heart is cone - shaped , with its base positioned upwards and tapering down to the apex . An adult heart has a mass of 250 -- 350 grams ( 9 -- 12 oz ) . The heart is typically the size of a fist : 12 cm ( 5 in ) in length , 8 cm ( 3.5 in ) wide , and 6 cm ( 2.5 in ) in thickness . Well - trained athletes can have much larger hearts due to the effects of exercise on the heart muscle , similar to the response of skeletal muscle . </P>
which side of the heart is the largest
which side of the heart is the largest
the left heart
the left heart