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3 Phases of Plyometric Training


These days when I walk around my gym I feel like I always see someone jumping over boxes, throwing medicine balls up to the ceiling, or hopping around like a rabbit. When I go over to these people and ask them why they're doing these specific exercises, their plyometricstypical response is either they have a friend that showed this to them or they saw it in on the internet. What they need to understand is that all of the above are variations of plyometric training.

In this week’s blog I would like to explain exactly what plyometric training is, what the three phases of plyometrics are, and point to some evidence-based research showing how plyometric training can help you.

Plyometric training is defined as a quick powerful movement involving an eccentric contraction followed immediately by an explosive concentric contraction.

Phase One

In the first phase of plyometrics (the Eccentric Phase, also referred to as the “loading” or “cocking” phase), energy is stored in the muscle in preparation for the following phase.  

Phase Two

In the second phase of plyometrics (the Amortization Phase), the muscle with the stored energy is stabilized in preparation for the final phase. For optimal performance, this stage is rapid in order to create a more powerful response.

Phase Three

The third and final phase is the Concentric Phase, also referred to as the unloading phase. This phase occurs immediately after the amortization phase which results in the use of the energy stored in that particular muscle. 

"In 2003, Luebbers et al., In a randomized controlled trial with 19 subjects demonstrated that a four week and seven-week plyometric training program enhanced anaerobic power and vertical jump height.

In 2004, Chimera et al., completed a pre-post test control study with 20 healthy Division 1 female athletes, which found that a six week plyometric training program improved hip abductor/abductor coactivation ratios that help control valgus moments at the knee during landing. In addition, the athletes also had significant increase in both sprint speed and vertical jump." 1

As with all training programs, the individual should systematically work themselves up to a level where they can perform plyometric training properly and safely. The individual should have good levels of core strength, flexibility and balance before attempting an extensive plyometric training program.  

Once the above level is attained, the individual will need to overload the muscles to avoid plateau. This can be achieved by jumping greater distances, dropping from further heights, or progressing from two legged to one legged jumps. 

Happy Hopping  :)

1Clark, Micheal, Scott Lucett, and Donald T. Kirkendall. "CHAPTER 8."NASM's Essentials of Sports Performance Training. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins, 2010. 208. Print.

Please consult your physician before staring any exercise regimen. The information presented in this article is in no way intended as medical advice or as a substitute for medical treatment.

Clark, Micheal, Scott Lucett, and Donald T. Kirkendall. "CHAPTER 8." NASM's Essentials of Sports Performance Training. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins, 2010. 208. Print.


Love the article. What advice can you gicve to someone with bad knees (ACL reconstruction). Plymetrics are very hard to do properly when the knees feel like they will not support the load of the exercise. is there a modification to these exercises that you can reccomend? Thank you.
Posted @ Monday, December 17, 2012 10:41 AM by Michael Tenebruso
Thanks Mike! Without going to in depth on blog site, I would try Dumbell Bench Step Ups, Ladder work (nylon ladders on floor doing various patterns in and out of spaces), and some Bosu work.
Posted @ Tuesday, December 18, 2012 5:22 PM by Marc Siegel
Nicely written Marc. Very informative. I've done plyometrics for years...didn't realize how in depth it gets.
Posted @ Thursday, December 20, 2012 1:34 PM by Eric
Very good article Marc! I love plyometrics.
Posted @ Wednesday, January 02, 2013 8:34 AM by Andre
Nice article. Just wondering if Plyometrics are recommended for all ages and fitness levels. I have been doing some Plyometrics as part of the Insanity program and wasn't sure if I am setting myself up for knee issues later in life by doing all of the jumps.
Posted @ Thursday, January 03, 2013 5:48 PM by Dan Carroll
@ Eric , thank you... @ Andre, thank you... @ Dan, That is a very tough questions answer. In my opinion to much of anything can be harmful even plyometrics. I have a corrective exercise specialist license that deals with injuries of ankles, knees, hips, back, shoulder and spine... Unfortunately I do treat people that have hurt themselves doing plyometrics... Now the question was where they doing it improperly, where they doing too much of it ? ...very important variables... I currently train individuals ranging from 22 to 60 using plyometrics. Hope that helps thanks for the comments
Posted @ Tuesday, January 08, 2013 11:56 AM by Marc Siegel
Will def add plyo to my weight training routine. Thanks Marc for the great info!!!
Posted @ Wednesday, February 27, 2013 9:47 PM by Helen
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