IFPA Trainer Practice Exam

The increase in diameter believed to occur through remodeling of protein within the cell and an increase in the number of actin and myosin filaments, along with sarcomere addition, refers to ______.

1. Hyperplasia

2. Hypertrophy

3. Atrophy

4. Growth

The correct answer is: Hypertrophy

The increase in diameter through remodeling of proteins within the cell and the addition of more actin and myosin filaments, along with the addition of sarcomeres, is indicative of hypertrophy. Hypertrophy specifically refers to the increase in the size of muscle fibers due to an increase in the volume of the cellular components, including proteins like actin and myosin. This process often occurs in response to resistance training or other forms of physical stress that challenge the muscle, leading to adaptations that enhance muscle strength and size. Hyperplasia, on the other hand, refers to an increase in the number of cells rather than the size of existing cells. It is not directly associated with the remodeling of existing muscle fibers and the addition of sarcomeres. Atrophy describes the decrease in muscle size and function, often due to disuse or injury, while growth is a more general term that lacks the specific physiological context implied in this question. Hence, the term that best fits the process described is hypertrophy.