By Kathleen Hank, DPT
Both upper extremity and lower extremity plyometric exercises are used for rehabilitation or performance enhancement. The concept of plyometrics is used as part of functional movement patterns when performing a sport. Plyometric training uses the physiological phenomenon of a stretch-shortening cycle to enhance the ability of the neuromuscular system to produce maximal force in the shortest amount of time possible. (1)
Plyometric exercises are high-velocity movements that pre-stretch muscles through eccentric contractions, briefly store elastic energy, and then release kinetic energy to produce a powerful concentric contraction.(2) During overhead sports, the shoulder must accept high joint loads generated by the lower extremity and trunk and efficiently transfer that energy to the upper extremity.(2)
The term amortization is used to describe the time from the end of the eccentric pre-stretch to the onset of the concentric action.(3) This phase is key to the performance of plyometrics. Plyometric movement is more effective and powerful with a shorter amortization time because the stored energy is used efficiently during transition.(3)
Potential Training Benefits of Plyometric Exercises:
-increased average power and velocity
-increased peak force and velocity of acceleration
-increased time for force development
-increased levels of muscle activation
-evokes stretch reflexes
-improved neural efficiency
-improved proprioception
-increased neuromuscular performance
Training programs should be individualized to each athlete and his or her sport to develop the best motor performance pattern through neuromuscular dynamic stability.(3) Plyometric training for the upper extremity should coincide with other resistance and flexibility training. Plyometric exercises can be performed in both closed and open kinetic chain positions of the upper extremity.
Examples of plyometric exercises for the shoulder complex:
-two hand chest pass
-two hand rotations from side
-two hand overhead throw
-one hand side arm throw
-90°/90° baseball throw
-eccentric deceleration followed by trunk rotation and concentric tosses
Blog Post written by Kathleen Hank, DPT. At the time of publishing Kathleen was in her Sports Ortho Clinical with me at Catz Physical Therapy.
References:
- Gjinovci B, Idrizovic K, Uljevic O, Sekulic D. Plyometric training improves sprinting, jumping and throwing capacities of high level female volleyball players better than skill-based conditioning. J Sports Sci Med. 2017;16:527-535.
- Swanik KA, Thomas SJ, Struminger AH, Bliven KCH, Kelly JD, Swanik CB. The effect of shoulder plyometric training on amortization time and upper-extremity kinematics. J Sport Rehabil. 2016;25(4):315-323. doi:10.1123/jsr.2015-0005
- Davies G, Riemann BL, Manske R. Current concepts of plyometric exercise. Int J Sports Phys Ther. 2015;10(6):760-786.