The split jerk (or jerk) is not only a unilateral movement, but among competitive weightlifters, we never change which leg is the lead leg. In American football, a punter/kicker has one job: kick the ball and kick it far. They spend hours practicing that kick with the same leg because it is sport specific.
Weightlifting is no different when it comes to the lead leg of an athlete’s jerk. We look for the most optimal and stable position for the athlete as they try to control max weights overhead. When an athlete finds that optimal position, they not only perform the lift correctly, they demonstrate the ability to change direction and absorb force under load—an element of strength needed by all athletes, regardless of sport.
In the sport of weightlifting, my friend and mentor Phil Sabatini (president of East Coast Gold Weightlifting) is fond of saying, “Clean is for show, jerk is for the dough.” In competition, you don’t get bonus points for having a really strong clean if you can’t jerk the bar over your head. It’s either a make or a miss. Having a strong and technically proficient jerk is the best way to ensure that after doing all that work to stand up the clean, you don’t lose it all, draw red lights, and blow the whole lift by missing the jerk.
From a coaching perspective, we look for a vertical line from the barbell, down the spine, and into the hips, supported by the athlete’s center of gravity. There is a reason the lift is called a split jerk and not a lunge jerk. In the split squat position, the legs are equidistant from the hips. The hips are vertically in line with the torso, and the athlete’s center of gravity is balanced between both legs.
An athlete cannot maintain the vertical hip position throughout the movement if their back knee is straight or “locked out.” When the athlete lunges into the catch position, their center of gravity shifts forward and back. This makes it vastly more difficult for an athlete to stabilize a barbell overhead, as we now have an added (though unnecessary) vector of force.
A major problem we see in the catch position of the jerk is that lifters often catch the bar overhead with a locked back knee. This is problematic because it will ultimately limit how much weight they can jerk, as they will be out of position and unable to drop low enough under the bar at heavier weights. Coaching the split position is one thing, but performing it dynamically can be confusing for athletes.
Video 1. For beginners especially, I like to focus on the footwork first, then slowly add in the upper body.
The quick footwork drill above reinforces the proper way to transition from a bilateral to unilateral stance. This helps the athlete find balance in the lower body and reinforces the position of the legs before adding a barbell. Athletes must be trained and confident to bend their back knee in the split jerk position because the back knee matters!
As athletes perform the lift, starting from the top-down, the arms should be locked out overhead, with the bar directly over the spine. The shoulder joint is in between internal and external rotation, and the lats are engaged to support the barbell overhead. The scapula is protracted and in a slight upward rotation. Moving down the body, the t-spine should be neutral, and the rib cage should be closed. The shin of the front leg is vertical, and the knee is directly over the top of the front ankle. The back knee should be unlocked and slightly bent.Some lifters will have more of an exaggerated bent knee than others, but in any case, they should never lock the back knee, says @nicc__marie. Click To Tweet
Some lifters will have more of an exaggerated bent knee than others, but in any case, they should never lock the back knee. For more information on the split jerk position and some other tips for improvement, you can read my article “Split Jerk Considerations.”
A locked back leg causes two big issues for the jerk. Due to the timing of the legs and the barbell overhead, it can be an orthopedic recipe for disaster. The athlete’s feet come into contact with the floor slightly ahead of the barbell being locked out overhead. If the back knee is pushed into extension, it will be more dangerous to receive the load overhead without some type of compensation or shift of the hips. This can cause unwanted hyperextension in the low back and puts more strain on the hip flexors.
From a technique perspective, having the back knee straight makes it more difficult for the athlete to drop low enough under the barbell. The jerk encompasses similar principles of physics as the clean and the snatch. The athlete is moving under the bar, not pressing it up. Without a bent back knee, it becomes a lot more difficult for the athlete to drop underneath, which means they must drive heavier weight higher up into the air. And we all know who wins in that scenario…gravity.
Understanding that the back knee should be bent in the catch position is one thing, but executing it is another. Sometimes it’s the muscular strengths and weaknesses of the athlete that can cause this technical error. When an athlete locks their the knee, it shows that they are either biasing the quad for stability or incapable of stabilizing through the glute. When the athlete locks the back knee, they are trying to find stability in the split position, thinking that a locked or “stiff” back knee will provide them with the ability to stop the barbell overhead and maintain the necessary position before they recover.
If an athlete has less than ideal mobility in their shoulders in the overhead position, they will compensate by opening up the rib cage and extending into the thoracic and lumber spines. As the rib cage opens, one of two things can happen:
- The athlete will attempt to bend their knee, causing the bar to end up too far behind them and leading to a missed lift.
- They will be forced to lock the back knee in extension to try and maintain the correct bar path despite their lack of mobility. When this happens, the athlete’s back knee inherently locks—if not, the barbell will end up too far back behind them, causing them to miss the lift.
In order for the athlete to feel comfortable unlocking the back knee, we must address their shoulder mobility and trunk stability issue.
Band and Stability Exercises
A commonly voiced concern from coaches and athletes when considering the Olympic movements is a lack of mobility. However, the importance of overhead stability must be emphasized. Specific to the jerk, the more confident and stable an athlete feels overhead, the more likely they are to drop under the bar and bend their back knee without hesitation. Knowing the shoulders are in a strong solid position allows them to place their focus on the lower half of the body during the catch position.Specific to the jerk, the more confident and stable an athlete feels overhead, the more likely they are to drop under the bar and bend their back knee without hesitation, says @nicc__marie. Click To Tweet
Crossover Symmetry bands are a great tool to help improve shoulder mobility while maintaining integrity in the trunk. If done correctly, the athlete has to utilize their core to maintain their trunk position and allow the shoulder blades to work independently of the spine. One of my favorites movements to do are snow angels: The athlete must maintain their position and not allow the band to pull the shoulders forward as the arms abduct into overhead flexion.
Video 2. Band y-raise to overhead squat.
As the athlete gets comfortable in a static position, we can move them into dynamic movement with the bands such as a band y-raise to overhead squat (above). The integrity of the trunk is still maintained, but the lower half is now more involved even though the focus is still on building overhead mobility. The athlete must maintain the overhead position as they lower down into the squat.
Bands aren’t the only tool that athletes can use to improve overhead mobility and trunk stability. One of my favorite exercises is the kettlebell halo. Similar to the snow angels, the athlete works on moving the shoulder blades independent of the ribs and torso. A way to progress this movement and make it weightlifting specific is with a KB halo from split. The athlete gets in the proper split position for the jerk and stabilizes as they circle the kettlebell around their head. In this position we are able to see if the athlete is learning to control the neutral spine required in the jerk.
Don’t Bend It Too Much
Now, there are always some exceptions to the “rule.” The caveat to this entire article is that if the back knee is too bent, then the athlete may feel a little less stable than with just a slightly bent back knee. For athletes who habitually shoot their back leg completely straight, I reinforce bending the back knee by cueing “back knee down” or “drive the back knee into the platform.” Does that mean I want the knee to get so low it almost slams into the ground? No! But they are so far into the wrong movement pattern in one direction that by overemphasizing the cue, they will find the proper position we are looking for.
Just like every other movement in weightlifting, various athletes’ jerk positions will all be slightly different based on their biomechanics, but it is important to remember that the principles to train this position are the same across the board. We need:
- Mobile shoulders and a stable torso.
- Strong hip flexors and adductors.
It is simply our job as coaches to understand whether the athlete locks that back leg because they are uncomfortable with the position or because a technique deficiency forces them to do so to get under the bar. In either case, set your athletes up with the tools to fix it and get some bend in that back knee!
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