How Eccentric Training Can Decrease the Risk of Injury and Improve Speed and Explosiveness

By Collis Spann

The eccentric phase of contractions, or better known as the “negatives,” carries a significant and unique responsibility when you train. The information in this post will illustrate how eccentric loading is a key component of your everyday movement, and how to reap the benefits of this type of training method. 

Whether your goals are to increase strength, decrease susceptibility to injury, or improve sports performance, eccentric training can assist in making them attainable.

Movement

Eccentric AKA “negative” training is an important training tool that can be beneficial to all types of athletes. Recent research demonstrates the many ways athletes can benefit from eccentric training; i.e. increases in performance, strength, hypertrophy (size), and injury prevention/recovery.

First let's explain what an Eccentric contraction is. An eccentric contraction occurs when the resistive force (load) is greater than the contractile force (muscle) causing the muscle to lengthen. (1) For example as you slowly sit onto a chair your quadriceps and glutes are lengthening and producing force to control your descent.

Why is eccentric strength important?

Most dynamic/athletic activities require a great amount of eccentric contractions controlling the body through motion and the majority of muscular injuries occur due to weakness of the eccentric phase. Weakness in the eccentric phase has been shown to be a risk factor for many injuries. A couple of examples would be: weakness of the hamstring eccentrically increases the risk of hamstring strains/tears at late swing phase of the run/sprint (2) and weakness of the glutes, especially gluteus medius, has been shown to increase the risk of patellofemoral pain syndrome. (3). Eccentric training (ET) can change the optimum length of tension development in a muscle. (4) Optimum force production usually occurs somewhere around mid-range of a muscle contraction.

ET allows for increased production at longer ranges of contraction where muscles are usually weak and most injuries occur. Moreover ET also causes a process called mechanotransduction in muscle tendons, which cause matrix remodeling and cellular proliferation AKA stronger healthier tendons. (5)  ET is utilized frequently in bodybuilding for its hypertrophy capabilities, as well as in rehabilitation practices to rehabilitate clients from surgeries and/or injuries.

Strength

The eccentric muscle contraction is a very vital and significant portion to one’s training. It is the most taxing muscular contractions of the three so it should be proceeded and executed with caution. Limit your eccentric workouts to a few times a month. In plyometrics the “stretch-shortening cycle” the most important muscular contraction is the eccentric and/or amortization phase. The eccentric phase is found in several different facets of sports performance and athletics. For example, it is involved in:

  • Pre-tension of the muscle prior to a concentric contraction
  • Stopping, faking, cutting, accelerating when you are running and make a quick stop or in a jump down action in which the eccentric contraction holds you from collapsing and generates the force to continue action or exert more force
  • A repelling action since it re-tenses the muscle prior to pushing an object away from you

A strong eccentric contraction will push the muscle action to optimal performance. The muscles are very elastic and resilient and when they are stretched and tensed they exhibit great forces to return to its original state.  

There are many ways to utilize the amortization phase in eccentric training and it is done so without knowing. Sticking with plyometrics, jumping exercises are the most common way and well-known, the eccentric muscular contraction in jumping exercises is used as an example frequently and throughout teachings to illustrate the importance of utilizing the eccentric muscular contraction to get maximal concentric contraction.

Bounding exercises as well will help in developing ground contact force, which will help in development of speed, stride length, stride rate, and power output. Bounding, depth jumps, and jumps generate the highest amount of force during sporting events. Power output is determined by the amount of ground contact force an athlete can exert during the pushing action with each step in starting, accelerating and sprinting, which are all major components of speed training (Dintiman & Ward, 2011). Furthermore, depth jumps or “shock exercises” are specific form of jumps that require the athlete to drop from an elevated platform to a vertical or broad jump by quickly rebounding and minimizing the ground-to-contact time. These jumps stimulate starting force and assist in producing sharp stretch reflexes.

The mechanical stretch of all soft tissues is improved through such measures, and this translates to improved reaction speed during explosive sporting events. Plyometrics assist in shortening the time of switching from an eccentric muscle action to a concentric action of the takeoff itself (Starzynski & Sozanski, 1995). Plyometrics are a great way to build general explosive strength and help in reactive speed. It is to be remembered that depth jumps and “shock exercises” put a great deal of stress on the lower limbs, so they are to be implemented with caution and if the athlete has no experience they are to seek a coach.

Eccentric training is a must and involved in every method, style, and philosophy of training, but it must be executed with caution. Eccentric training is the most taxing muscular contraction of the three and will depress the CNS the quickest, but also depletes glycogen storages the fastest as well. There is several literature out there to assist in programming eccentric training and how best to utilize it according to your goals and respected sports. Proceed with caution, but if implemented correctly and under guidance, the progress will be steady and the development of the many different types of strength will be great.

For more information on how to implement eccentric training safely and properly into your daily programming please message us here or email us at collis@hit-training.com.

References:

Starzynski, T., Sozanski, H. (1995). Explosive Power and Jumping Ability for All Sports: Atlas of Exercises. Island Pond, VT: Stadion Publishing Company, Inc.

Hattfield, F. C. (1989). Power: A Scientific Approach: advanced musclebuilding techniques for explosive strength. Chicago, Illinois: Contemporary Books, Inc.

Dintiman, G.B., Ward, R.D. (2011). Encyclopedia of Sports Speed: Improving Playing Speed for Sports Competition. Kill Devils Hill, NC: National Association of Speed and Explosion (NASE).

1) Essentials of Strength Training and Conditioning, 3rd edition, 2011

2) Petersen, J., K. Thorborg, M. B. Nielsen, E. Budtz-Jorgensen, and P. Holmich. "Preventive Effect of Eccentric Training on Acute Hamstring Injuries in Men's Soccer: A Cluster-Randomized Controlled Trial." The American Journal of Sports Medicine (2011): 2296-303.

3) Barton, C. J., S. Lack, P. Malliaras, and D. Morrissey. "Gluteal Muscle Activity and Patellofemoral Pain Syndrome: A Systematic Review." British Journal of Sports Medicine (2012): 207-14.

4) Brughelli, Matt, and John Cronin. "Altering the Length-Tension Relationship with Eccentric Exercise." Sports Medicine: 807-26. Print.

5) Lorenz, Daniel. "Eccentric Exercise Interventions for Tendinopathies." Strength and Conditioning Journal: 90-98. Print.