November 27, 2011

Double Contraction Reps - Correct The Imbalances Created From Full Ranges Of Motion

A Gift And A Curse – Full Range Of Motion

Loading and fatigue aside, the amount of tension a muscle is under will vary based on the joint angle, and angle of contraction, meaning the same muscle can, and will, be under more, or less, tension at different ranges of motion during the exact same movement. Thus, performing a full range of motion can facilitate the development of muscular imbalances, especially with an overreliance on compound movements.

This is not to suggest the removal of compound movements in favor isolation movements, as they are susceptible to creating imbalances as well, albeit on a much less noticeable scale, but rather to keep a keen eye on possible imbalances that can result from performing a lot of compound movements through a full range of motion. Even when imbalances occur, it is not always completely necessary to remove the (compound) movement that caused it, as it’s not necessarily the movement that caused it, but rather the way in which it was performed that contributed to the imbalance.

Because different muscles are under greater levels of stress at differing ranges of motion, especially during compound movements, modifying the way in which the exercise is performed can help correct the same imbalances that the movement created in the first place, by simply emphasizing the range of the lift in which the targeted muscles are most active.


Double Contraction

The double contraction technique is exactly as it sounds – a full rep is performed, followed by a partial rep at a specific range of motion, so that twice as many reps are performed at that range in comparison to those performed through a full range. This is one of the most effective ways to correct imbalances created with full range of motion training, or simply place a muscle under greater levels of tension than would happen under normal conditions to stimulate growth.

The range in which the double contraction partial rep is performed should obviously be determined by the goal, and can be applied to any exercise, but two movements in which this technique is especially effective are the squat, and all barbell presses.

Double Contraction Squats

The vastus medialis oblique (VMO) head of the quad is relatively underdeveloped in relation to the other heads of the quad, primarily as a result of it being most active at end ranges of knee flexion and extension – two positions in which the knee is rarely ever optimally loaded. In this case, a double contraction in the bottom range of the squat doubles the time that the VMO is under optimal tension, as the amount of weight that can be used is limited to how much can be lifted in the weakest range, which is the range in which the VMO is most active.

Double Contraction Presses (All Angles)

Barbell presses are multi-phase lifts in which the tension shifts from one prime mover to another – at the bottom range the chest/shoulders are the main driver, at the top range the triceps are the main driver. Therefore, a double contraction at the bottom range doubles the time in which the chest/shoulders are under tension, while a double contraction at the top range doubles the time in which the triceps are under tension. Obviously the angle of the press, along with the grip width, will determine how heavily emphasized the chest, shoulders, and triceps are recruited.


If you have any questions about the double contraction technique, feel free to contact me at ben@paramounttraining.ca. I'm available for online consulting and personalized program design, as well as one on one training if you are located in the Greater Toronto Area (GTA).

1 comment:

  1. What about 1 1/4 reps on the CNS? Obviously resistance training in general allows our motor units to become more efficient, but would 1 1/4 reps achieve this better than normal reps?

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