Prolonged endurance training increases the size of the left ventricle with little change in ventricular wall thickness.

• A. True
• B. False
• C. Cannot be determined
• D. Not enough data

Answer: (A)

Endurance training creates a volume overload on the heart, so it adapts by enlarging the left ventricular chamber rather than severely thickening the walls. This type of remodeling, called eccentric hypertrophy, involves adding sarcomeres in series, which lengthens the cardiomyocytes and expands the LV end-diastolic diameter. Wall thickness rises only modestly, so the wall doesn’t thicken as much as the chamber enlarges, and relative wall thickness remains normal or even slightly reduced. This pattern contrasts with resistance training, where the heart often thickens its walls (concentric hypertrophy) with less change in chamber size. So the statement accurately reflects how prolonged endurance training features left ventricular enlargement with little change in wall thickness.