Overspeed Eccentrics

Eccentric exercise is when the muscle is in the actively lengthened; concentric exercise is when the muscle is actively shortened. An example would be during a bicep curl, the up motion is the concentric part of the exercise, the downward motion is the eccentric.  Eccentrics are sometimes call active ‘negatives.’

Overspeed Eccentrics

Powerlifting coach Louie Simmons (2001, 2007; of Westside Barbell) came up with a system of stressing the eccentric system with chains and bands.  This type of resistance was eventually called overspeed eccentrics (or as Louie Simmons called it “shock training with weights”).

To take advantage of eccentric training for maximum strength gains in lifting exercises you should use the eccentric/yielding portion to accumulate kinetic energy that you will transform into elastic energy, reflex energy, and ultimately greater force production in the overcoming portion of the lift.

The ‘overspeed eccentrics’ technique results in an accumulation of kinetic energy that results in greater force production and elastic energy (Thibaudeau & Schwartz, 2007). Farthing and Chilibeck (2003) explain that training programs that utilize eccentric contractions at fast velocities remove neural inhibition, serving as a mechanism for injury protection. In order to protect the muscle from being over stretched, the message that the muscles are being lengthened is sent to the spinal cord by way of a one synaptic junction, which causes the spinal cord to act on this information, by contracting the muscle that is being stretched and inhibiting the contraction of the antagonist muscles, bypassing sending the message to the brain (known as the ‘stretch reflex’). Taking advantage of the elasticity of the muscle and the stretch reflex is referred to as the stretch-shorten cycle, and it has been shown that the faster the muscle is stretched eccentrically, the greater the force will be on the following concentric contraction.

A perfect example of a body weight exercise would be bounding box jumps. As the person drops off the box, the eccentric contraction is what stops us from crashing into the floor. If we immediately bound back up on the box, we use that sensory inhibition to benefit our jump.

Notes on when to perform overspeed eccentrics

In general, overspeed eccentrics should be used in athletes who want to develop power (applying force quickly to a weight). For example, these exercise will be great for olympic weightlifting, but may not be as important for exercise endurance exercises.

Fatigue interferes with the ability to recruit these motor units of the muscles. A person needs to have the ability to recruit these  motor units, thus, longer rest periods are needed and they should not be performed everyday.

The benefits (based on research)

A study by Farthing and Chilibeck (2003) found that eccentric fast training was the most effective for muscle hypertrophy and strength gain.  Paddon-Jones and colleagues (2001), found that a fast eccentric training program led to a decrease in type I fibers (from 53.8% to 39.1%; i.e., slow twitch fibers), while type IIb fiber percentage increased (from 5.8% to 12.9%; fast-twitch fibers).

Cook and colleagues (2013) studied semi-pro athletes and put them on a rigorous training program that consisted of: 1) traditional resistance training alone, 2) eccentric training alone, 3) traditional concentric training combined with over-speed exercises, and 4) eccentric training combined with over-speed exercises. They found that bench press, squat, and peak power all increased with the eccentric training with over-speed stimuli above and beyond the other groups.

(see here for an article by Charles Poliquin summarizing similar research on older adults)

How do I apply this information

Using elastic bands attached to a bar has a positive effect because the bands will actually try to “blast” the bar down, bringing it down faster than if only gravity was acting on it. Chains will act as additional weight, while the elastic bands increase kinetic energy.

A thought on banded pullups

Based on this research, the assisted banded pull-up might be having an adverse effect on our strength gains.  That is, the band actually slows down the eccentric portion of the movement and may take away from some of the overspeed eccentric response.  A suggestion might be to do ring pull-ups with feet on the ground as an alternative. The person could try to allow themself to drop faster into the next movement to benefit from the overspeed eccentric response.  A bonus movement would be to connect bands to an anchor on the ground, wrap the bands around the shoulders, and to use the bands to actively pull the person down (pull-ups with the bands pulling down rather than assisting; only for people who can do strict pull-ups with the added resistance).

Banded Kettlebell Swings

In addition to the ballistic concentric acceleration of the kettlebell during the forward swing phase, an active acceleration of the kettlebell on the backswing could be used to get the overspeed eccentric effect. Instead of letting the kettlebell accelerate downwards under gravitational forces, the user could actively pull the kettlebell down, or have a partner push the kettlebell down at the top swing, increasing the speed of the eccentric muscle contraction of the posterior chain.

In order to take advantage of overspeed eccentrics during the two arm kettlebell swing, two things must be present 1) a fast backswing portion of the kettlebell swing and 2) a rapid switch between the eccentric muscle contractions of the backswing into a concentric contraction of the forward swing. This technique can be implemented into the kettlebell swing by a) having the kettlebell user actively pull the kettlebell down during the backswing,b) a partner forcefully pushes the kettlebell down when the kettlebell reaches the top swing, or c) using bands to actively pull the kettlebell down (see video below).

Cook, C. J., Beaven, C. M., & Kilduff, L. P. (2013). Three weeks of eccentric training combined with overspeed exercises enhances power and running speed performance gains in trained athletes. Journal of Strength and Conditioning Research / National Strength & Conditioning Association27(5), 1280–1286. doi:10.1519/JSC.0b013e3182679278
Farthing, J. P., & Chilibeck, P. D. (2003). The effects of eccentric and concentric training at different velocities on muscle hypertrophy. European Journal of Applied Physiology, 89(6), 578–586. doi:10.1007/s00421-003-0842-2

Paddon-Jones, D., Leveritt, M., Lonergan, A., Abernethy, P. (2001). Adaptation to chronic eccentric exercise in humans: the influence of contraction velocity. Eur J Appl Physiol 85:466–471

Simmons, L. (2001). Explosive power and strength. http://www.westside-barbell.com/index.php/the-westside-barbell-university/articles-by-louie-simmons/strength-training-101/321-explosive-power-and-strength

Simmons, L. (2007). Eccentric unloading. Powerlifting USA, 30(10). Retrieved from http://www.westside-barbell.com/index.php/the-westside-barbell-university/articles-by-louie-simmons/articles-published-in-2007/390-eccentric-unloading
Stevenson, M. W., Warpeha, J. M., Dietz, C. C., Giveans, R. M., & Erdman, A. G. (2010). Acute effects of elastic bands during the free-weight barbell back squat exercise on velocity, power, and force production. Journal of Strength and Conditioning Research / National Strength & Conditioning Association, 24(11), 2944–2954. doi:10.1519/JSC.0b013e3181db25de
Thibaudeau, C., & Schwartz, T. (2007). Theory and Application of Modern Strength and Power Methods. F Lepine Pub.
Blog post by Craig Marker