There are two major components to power: force and velocity. It’s been suggested that prior to a young athlete hitting his or her growth spurt, velocity of muscle contraction is primarily responsible for the expression of power. However, subsequent to an athlete’s growth spurt, increases in force production end up being the major factor in power expression. Therefore, when developing young athletes, training fast and explosive movements may set them up for greater success later on down the road.
In team sports like soccer, basketball and football, efficient and explosive movement in a variety of planes is required for successful competition. As coaches, we sometimes fail to remember the importance of this in our programming and tend to neglect exercises that train movement in various directions. By doing so, we may be providing a disservice to our athletes and failing to develop them optimally.
In a new study published ahead of print in the Journal of Strength and Conditioning Research, the effectiveness of various plyometric training programs was tested in adolescent athletes (~11 years of age). Forty young soccer players were divided into a control group, vertical plyo group, horizontal plyo group or a combined vertical and horizontal plyo group. Before and after a 6 week training period, a battery of performance tests were evaluated including; vertical and horizontal counter-movement jumps, reactive strength index, multiple bounds, agility, 30 m speed, balance, maximal kicking velocity and the Yo-Yo Intermittent Recovery Test Level 1. All training sessions were incorporated into routine soccer practices. The training programs were equalized for total volume and were progressive in nature.
The results showed that the control group showed no differences in any performance variable following the program with the exception of a small improvement in the Yo-Yo test. The group that trained vertical plyos (i.e., the vertical plyo from and combined group) tended to increase mostly in variables that required vertical force production and vice versa for the horizontal plyo and combined group. Only the combined group showed the biggest improvement across the board on all performance tests, outperforming both horizontal plyo only and vertical plyo only groups.
This study demonstrates the importance of developing rapid force production in both vertical and horizontal planes for inducing significant improvements in performance variables in young athletes. The law of specificity in training must not be overlooked for optimal development of athletic performance. All physical demands of a sport must be considered, evaluated and trained to see improvement. Dedicating a 15-20 minute period during a practice session to plyometric training can have a major impact on player performance and would be time well spent.
Reference:
Ramírez-Campillo, R., Gallardo, F., Henriquez-Olguín, C., Meylan, C., Martínez, C., Álvarez, C., … & Izquierdo, M. (2014) Effect of vertical, horizontal and combined plyometric training on explosive, balance and endurance performance of young soccer players. Journal of Strength and Conditioning Research.