Reliability of isokinetic tests of velocity? and contraction intensity?dependent plantar flexor mechanical properties

“Flexibility” tests are traditionally performed voluntarily relaxed by rotating a joint slowly; however, functional activities rapidly with voluntary/reflexive muscle activity. Here, we describe the reliabilities and differences in maximum ankle range of motion (ROMmax) plantar flexor mechanical properties at several velocities levels voluntary force from new test protocol on commercially available dynamometer. Fifteen participants had their dorsiflexed 5, 30, 60° s?1 two conditions: while producing 40% 60% maximal eccentric torque. Commonly reported variables describing ROMmax resistance to stretch were subsequently calculated torque angle data. Absolute (coefficient variation (CV%) typical error) relative (ICC2,1) determined across testing days (?72 h). reliability was good 30 moderate 5° s?1, despite CVs ? 10% for all velocities. Tests activity only reliable when CV 8%. For most variables, rank order differed between slow-velocity, test, those faster speeds or activation, indicating different information. A person's flexibility status during fast active stretches tended differ traditional relaxed, slow-velocity test. Thus, “flexibility” should be completed under conditions velocity production, clinicians researchers consider slightly larger between-day variability tests.