Enhanced muscle activity during lumbar extension exercise with pelvic stabilization

Area of Science:

• Biomechanics
• Exercise Physiology
• Rehabilitation Science

Background:

• The multifidus (MF) and iliocostalis lumborum (IL) are key lumbar extensor muscles.
• Understanding muscle activation patterns during exercise is crucial for effective rehabilitation and training.
• Pelvic stability's role in modulating these muscle activities during dynamic movements requires further investigation.

Purpose of the Study:

• To determine if pelvic stabilization influences the electromyographic (EMG) activity of the MF and IL muscles during dynamic lumbar extension exercises.
• To compare MF and IL muscle activation with and without pelvic stabilization under isometric and dynamic conditions.

Main Methods:

• Nine healthy males underwent isometric lumbar extension strength testing and dynamic extension exercises in a seated position.
• EMG activity of MF and IL muscles was recorded during isometric tests at specific trunk angles (110°, 146°, 182°).
• Muscle activity was also measured during dynamic exercises at 50% of maximum isometric strength, with and without pelvic stabilization.

Main Results:

• Both MF and IL muscle activities were significantly higher with pelvic stabilization compared to without stabilization across all tested trunk angles during isometric testing (P<0.05).
• A similar significant increase in MF and IL muscle activity was observed with pelvic stabilization during dynamic extension exercise (P<0.05).

Conclusions:

• Pelvic stabilization enhances the activation of the multifidus and iliocostalis lumborum muscles during both isometric and dynamic lumbar extension exercises.
• Lumbar extension exercises incorporating pelvic stabilization may offer greater potential for strengthening these crucial trunk extensor muscles.