The Effects of Self-induced and Therapist-assisted Lower-limb PNF Pattern Training on the Activation of Contralateral Muscles

Activation of the gluteus medius according to load during horizontal hip abduction in a one-leg stance

[Purpose] This study researched the influences of different loads on muscle activity of the posterior fibers of the gluteus medius in a one-leg standing position. [Subjects] Twenty-four healthy adult men participated in this study. [Methods] All participants performed the one-leg standing position under four conditions: the standard no-load condition, in which the non-weight-bearing leg was lifted and kept parallel to the back and then pelvic or lumbar rotation was performed without thorax rotation, and the 0 kg, 1 kg, and 3 kg load conditions, in which horizontal shoulder abduction was performed with a load of 0 kg, 1 kg, or 3 kg added to the hand. The electromyographic activity of the posterior fibers of the gluteus medius was measured using a wireless surface electromyography under all conditions. The electromyographic activity of each muscle under the four conditions during the one-leg stance was analyzed using one-way analysis of variance. [Results] The electromyographic activity of the posterior fiber of the gluteus medius was significantly increased under the 3 kg load condition compared with the no-load, 0 kg load, and 1 kg load conditions. [Conclusion] These findings indicated that muscle activation is affected by increases in load in the one-leg standing position. The load on the upper extremity influences the muscle activity of the contralateral lower extremity.

Surface electromyographic recordings after passive and active motion along the posterior myofascial kinematic chain in healthy male subjects

OBJECTIVE

To map the association of muscle activations along the superficial back line (SBL) using separate conditions of active range of motion with and without resistance and passive range of motion.

METHOD

Using surface electromyography, electrodes were placed at specific points along the SBL. Twenty healthy adult males (aged 25.35 ± 1.24 years and body mass index 23.78 ± 2.12) underwent five test conditions. Conditions 1-3 involved passive movement, active movement and active movement against maximum isometric resistance (IR) of the right gastrocnemius and conditions 4 and 5 involved neck extension without and with isometric resistance from prone position.

RESULTS

Passive and active motion without resistance found no significant (p > 0.05) correlations at any electrodes. Maximum IR yielded significant (p < 0.05) correlations with medium to very strong correlations at almost all electrodes. Neck extension without and with resistance showed significant medium to very strong correlations though the posterior superior iliac spine and right hamstring, respectively.

CONCLUSION

Results demonstrated significant associations between the test condition muscle activations and muscle activations along the contiguous SBL. Thus, showing a need for a complete evaluation of the SBL in patients suffering from myofascial pain at all locations along it.