During an experiment on skeletal muscle contraction, a muscle fiber is stimulated to contract isometrically. Which of the following parameters remain…

In an isometric contraction (iso = same, metric = length), the muscle length remains constant while the tension changes. During this contraction, sarcomeres shorten slightly as the series elastic elements stretch, but the overall muscle fiber length does not change. The A-band length is always constant during any muscle contraction, but the question asks what remains constant for the entire muscle fiber, and in isometric contraction, length is constant. Wait, A-band also remains constant, but 'Length of the muscle fiber' specifically defines isometric contraction. Actually, A-band remains constant in all contractions, but A-band length is a property of the sarcomere, not the whole fiber parameter defining the contraction type. The defining feature of isometric is constant muscle length.