Promoting longus colli muscle activation: Force direction in sitting matters.

Area of Science:

• Biomechanics and Exercise Physiology
• Neuromuscular Control of the Cervical Spine

Background:

• Limited evidence exists for prescribing deep neck flexor exercises outside of the supine position.
• Understanding optimal exercise positions and resistance types is crucial for effective rehabilitation.

Purpose of the Study:

• To compare deep neck flexor activation (longus colli and sternocleidomastoid) between supine and sitting positions.
• To evaluate the impact of different craniocervical flexion (CCF) exercise variations in sitting on muscle activation.

Main Methods:

• Twenty-four pain-free individuals performed 7 isometric CCF exercises (supine and sitting with elastic band resistance).
• Muscle activation of longus colli (LC) and sternocleidomastoid (SCM) was measured using ultrasound imaging.
• Statistical analysis (2-way ANOVA) determined the effects of exercise type and muscle on activation levels.

Main Results:

• Longus colli activation was similar between supine and sitting CCF exercises.
• Ipsilateral oblique resistance in sitting significantly enhanced longus colli activation compared to straight lateral resistance.
• Sternocleidomastoid activation was greater with ipsilateral lateral resistance compared to contralateral resistance.

Conclusions:

• Craniocervical flexion in supine and sitting positions yield comparable longus colli activation.
• In sitting, applying oblique resistance during lateral flexion with extension is most effective for longus colli activation.
• Caution is advised with straight lateral resistance forces in sitting due to potential for increased sternocleidomastoid activation.