The kettlebell clean and jerk is an exercise based around power and mobility. The demands of the exercise are systemic and demand high levels of concentration and ability. Part of the three main lifts in the sport of kettlebell competitions, the clean and jerk is understood to be one of the most demanding.
For this evaluation, I will break the movement up into two main parts the “clean” then the “jerk” and discuss both.
1) The Clean.
This portion of the lift begins with the kettlebells set about a foot in front of the practitioner. The arms are extended to reach the bells, the latissimus dorsi disengaged and the arms and hands pronated. The lower cervical spine is neutral with the atlanto-occipital joint slightly extended. This position on the cervical spine will be modified slightly as the “clean” progresses.
Once the athlete decides to begin the exercise, the fingers (distal and proximal interphalangeal joints) are flexed and strong. The latissimus dorsi engage and pull back adding to the shoulder and low back and pelvis stability due to their role in the posterior oblique fascia sling and their insertion into the thoracolumbar fascia. The scapular muscles (rhomboids and lower trap fibers) engage to depress and retract the scapula. The cervical spine retracts using the deep neck flexors and upper trapezius muscles. This retraction flexes the atlanto-occipital joints while extending the C3-C7 joints (Bogduk, N. 2002) creating a neutral cervical spine, also known as the cervical braced position.
The hike initiates the “clean”. The initial hike involved a rapid shoulder extension carrying the kettlebells between the legs. At this point, the hips take over creating momentum, but the upper extremity is not through. Initially, the elbows must Abduct to allow the kettlebell to clear the hips. The shoulders begin to Adduct and externally rotate, while the scapula retract and depresses causing the humerus to approximate the rib cage allowing the kettlebell to travel along the anterior midline and come to rest in what is known as the “racked” position on the upper chest. This is an interesting movement as it involves two planes of motion, the shoulder adducts horizontally in the transverse plan while simultaneously externally rotating in the coronal plane.
Once engaged, the wrists and fingers grip the bell and stay flexed until the movement is complete.
2) The Jerk
Now that the kettlebells have been brought to chest height the cervical spine is in its neutral packed position, the shoulders are in internal rotation, the humerus adducted and resting on the rib cage, the elbows flexed, the wrists and fingers flexed. We now begin the process of the “jerk” motion.
The shoulders drive the kettlebells up as they again externally rotate, abduct and flex to the overhead position. The humerus, beginning in a neutral position, drives from the sagittal plane until it reaches about 45 degrees where the arms and hands again begin to pronate creating a frontal plane progression of the humerus, ulna, radius, wrists, and fingers. The kettlebells finally come to rest overhead in a position with the shoulders fully flexed, the elbows extended, the wrists neutral and the fingers flexed gripping the kettlebells. There is a brief pause before the exercise is initiated again.
References:
Biel, A. (2010). Trail Guide to the Body (3rd ed.). Boulder, CO: Books of Discovery.
Bogduk, N. (2002). Biomechanics of the Cervical Spine. Physical Therapy of the Cervical and Thoracic Spine, 26-44.
Cipriano, J. J. (2003). Photographic manual of regional orthopaedic and neurological tests (4th ed.). Baltimore, MD: Lippincott Williams & Wilkins.
Vizniak, N. A., & Vizniak, N. A. (2014). Quick reference evidence based muscle manual student handbook. Vancouver, Canada: Professional Health Systems.
Vizniak, N. A. (2019). Evidence-informed orthopedic assessment. Vancouver, Canada: Professional Health Systems.