Do pre-adolescent athletes benefit from plyometrics?

Coaching youth sports teams presents many challenges for the coaching staff. Oftentimes, coaches may only be able to practice with their players as little as 1-2 times per week. The coaching staff must decide how they will budget their time with the kids to best educate them on the skills and fundamentals of the game as well as prepare them physically for the demands of competition. What effect, if any, would budgeting some time for plyometric training during regular practice time have on physical performance in this specific population? Do young athletes benefit from this type of training? Is time better served practicing sporting technique and developing conditioning?

A recent study published in the Journal of Strength and Conditioning Research by Michailidis et al (2013) investigated the effects of incorporating low intensity plyometrics into the practices of preadolescent male soccer players (age 10-11). The design of the study was simple, the control group (n=21) performed typical practices not involving plyometric training during a 12 week in-season consisting of 3 practices per week in addition to competition. The experimental group (n=24) followed the same schedule however plyomertic training was incorporated into practice twice per week (72 hours apart) for approximately 20-25 minutes (no change in session duration).

The first 6 weeks of plyometric training consisted of single and double leg hurdle hops (forward and lateral), lateral shuffles over a box, skipping and ladder agility/footwork drills. The second 6 weeks of training involved skipping, single and double leg box jumps and low intensity depth jumps. All sessions consisted of 4 exercises performed for 2-4 sets for 5-10 repetitions with 90-180s rest between sets. The researchers progressed the athletes according to standard procedures and had the drills performed on grass to limit impact forces.

All athletes were tested pre-training, at the mid point and post training. Testing parameters included VO2 max, 30m sprint test (10m, 20m included), Standling Long Jump, Multiple 5 Bounds Test, Various Vertical Jump Tests (counter-movement, single leg, Depth Jump), Lower body strength (10 rep max squat) and Anaerobic Power (Wingate test). Agility and kicking distance were measured to assess the dynamic correspondence of the training to sport specific skills.

The plyometric group saw marked increases in speed, jumping, bounding, leg strength, agility and kicking distance compared to the control group. These results suggest that supplementing specific sport practice with plyometric training as little as twice per week for 20-25 minutes per session can result in significant improvements in physical performance over typical practice alone. Incorporation of this type of training certainly warrants consideration. However, coaches must always prioritize the athlete’s safety and therefore should seek to educate themselves on how to implement this training safely and effectively.

Reference:

Michailidis, Y., Fatouros, I. G., Primpa, E., Michailidis, C., Avloniti, A., Chatzinikolaou, A., … & Kambas, A. (2013). Plyometrics’ Trainability in Preadolescent Soccer Athletes. The Journal of Strength & Conditioning Research, 27(1), 38-49.