Static loading of the knee joint results in modified single leg landing biomechanics

• DOI: 10.1371/journal.pone.0219648
• Publication Date: 2020-02-21T13:30:17Z
• Authors: Michael W. Olson
• Keywords: Biomechanics

Background External loading of the ligamentous tissues induces mechanical creep, which modifies neuromuscular response to perturbations. It is not well understood how creep affects athletic performance and contributes modifications knee biomechanics during functional tasks. Hypothesis/purpose The purpose this study was examine responses single leg drop landing perturbations before after passive joint. Methods Descriptive laboratory study. Male (n = 7) female 14) participants' (21.3 ± 2.1 yrs., 1.69 0.09 m, 69.3 13.0 kg) right hip, knee, ankle kinematics were assessed landings performed from a 30 cm height onto force platform 10 min protocol. Electromyography (EMG) signals recorded rectus femoris (RF), vastus lateralis (VL), medialis (VM), semimembranosus (SM), biceps (BF) muscles. protocol involved fixing joint at 35° static with perpendicular loads either 200 N (males) or 150 (females). Maximum, minimum, range motion (ROM), angular velocities for joints, while normalized EMG (NEMG), vertical ground reaction forces (VGRF), rate development (RFD) using ANOVAs. Alpha set 0.05. Results Maximum hip flexion velocity decreased (p < 0.01). Minimum increased 0.02). ad/abduction 0.001). Ankle ROM aVGRF RFD had non-significant trend 0.076). NAEMG significant between muscle groups Conclusion Distinct changes in parameters are attributed altered behavior may contribute landing.