Wednesday, November 28, 2007

Cutting-Edge Research: The Latest on Plyometric Training

Plyometric training is widely accepted as a method for increasing strength, power and sprint performance in athletes. Two recent studies provide new insight into the usefulness of plyometrics and present possible alternative training methods. Both studies appear in the May 2007 issue of the Journal of Strength and Conditioning Research.

One criticism of plyometric training is the high impact forces and forceful eccentric (or lengthening) muscle contractions increase the potential for injury and development of muscle soreness. To combat this, trainers recommend training on soft surfaces. Stemm and Jacobson compared the effectiveness of traditional land-based plyometric training to an aquatic-based program. In their study, subjects trained twice per week for six weeks. One group trained on land using a tumbling mat as a landing surface. The second group performed identical exercises in a pool filled with knee-level water. Following the program, both groups showed similar increases in vertical jump height. The results indicate that an aquatic-based program may be as effective as land-based training for improving muscular performance. The advantage of this type of program is that the water may reduce impact forces and lower the risk of musculoskeletal damage.

In the second study, Markovic and colleagues compared the effects of traditional plyometric training and sprint training on strength, power and sprint performance. In their 11-week study, one group trained three times per week using hurdle jumps and drop jumps (40-60cm, 4-7 sets of 10 reps). The second group trained by performing repeated sprints (10-50m, 3-4 sets of 3 reps). The researchers found that both training programs improved vertical and horizontal jump distance by 13-15%. However, sprint training was slightly more effective at improving 20m sprint and shuttle run performance. The results indicate that sprint training can be used as an effective method for improving muscular strength and power. Incorporating sprint training into a program of resistance and plyometric training might maximize the overall effectiveness for athletes striving to achieve a high level of performance.

Running speed and jumping ability are both critically important for success on the soccer pitch. Both of these studies suggest that explosive training using land-based or aquatic-based ploymetric exercises as well as repeated sprints can improve both parameters and have the potential to improve match-day performance.

References:

Stemm JD, Jacobson BH (2007) Comparison of land- and aquatic-based plyometric training on vertical jump performance. Journal of Strength and Conditioning Research. 21:568-571.

Markovic G, et al. (2007) Effects of sprint and plyometric training on muscle function and athletic performance. Journal o f Strength and Conditioning Research, 21:543-549.