Test-retest repeatability of electrically evoked isotonic power and isometric torque in the plantar flexors.

Electrically evoked isometric torque has good to excellent repeatability, but the degree of repeatability for electrically evoked isotonic power is unknown. We evaluated the test-retest repeatability of plantar flexion isometric torque and isotonic power evoked using brief tetanic trains at 10 and 50 Hz. Both torque and power had excellent (intraclass correlation coefficient >0.9) repeatability at low and high frequencies. Similar to isometric torque, electrically evoked isotonic power is a stable measure for studying dynamic muscle function.