Several articles have been written on injury prevention, with plyometric training as an example and technique for both injury prevention and sports preparation. In this particular article, I will outline how plyometric training influences the development of speed-strength capabilities and prevention of injuries.
For many trainers, a common topic of discussion centers around how to properly conduct sports preparation among athletes, while still preventing injuries that can occur within the athlete’s given sport. It is well known that the emergence of any injury can adversely affect the flow of sports training, and as a result, the sports form in its entirety.
For many athletes, acquiring an injury can significant hinder the athletes ability to perform at their maximum potential. While some athletes get “lucky”, and can get back on track with their training and sport, the vast majority of individuals are forced to end their sporting careers prematurely due to an injury.
In a utopic world, injuries would cease to exist for all athletes. Unfortunately, injuries play a significant role in any athlete’s sporting career, particularly in contact sports. The question then remains, in what severity will these injuries occur in, and most importantly, what can coaches do to assist their athletes when injuries occur?
To reduce the risk of injury from the start, coaches should introduce quality programs for sports training, and implement these programs diligently. In regards to injury prevention, there are many scholarly articles and resources available for coaches to utilize. Moreover, we have a constant flow of knowledge on injury prevention through other media outlets that will continue to develop. There is an infinite demand for research on injury prevention, resulting in the desire for optimal health of all athletes prior to engaging in any intense sports training or competition.
You can be the best, but if an injury says “it’s over,” an athlete’s career really can be over.
Factors and Mechanisms of Injury
Several intrinsic and extrinsic realms of injury exist, along with the etiology of contact and non-contact mechanisms that can result in injury. My goal is to connect injury prevention with plyometric training and propose this as one of the methods coaches can use to influence speed-strength capability.
Plyometric training fits well with other preventative programs such as proprioception, strength development, stretching exercises and complex neuromuscular training. Plyometric training can be defined as a quick eccentric-concentric muscle contraction. The main purpose is to increase the explosive power and ability for muscle-tendon system reaction.
Why connect plyometric training with speed-strength abilities?
Motor skills are plyometric training display a significant correlation. When we influence the development of exercise, for instance, explosive power, we in turn influence the development of speed, and vice versa. This phenomenon is termed transfer exercise. Therefore, plyometric training affects the development of speed, explosive strength, and flexibility.
Plyometrics and Injury Prevention
All programs geared towards sports preparation are consistent with one another. Each program has its place in sports preparation based on the periodization of the program.
When referencing plyometric training within the context of injury prevention, the development of strength, flexibility and muscle-tendon reactiveness are main factors to discuss. Improved flexibility provides better cushioning and control when high impact occurs during training or competition. The crux of flexibility lies in acceleration between eccentric-concentric cycles. However, this is only possible by first improving muscular and intramuscular coordination. This coordination depends on neuromuscular coordination, which will decrease the possibility of injury.
Effects of Plyometric Training
Some benefits of plyometric training are:
- The direct impact on the development of speed and explosive strength.
- The development of flexibility power — better depreciation and control over forces that occur during the performance of physical activity.
- Better muscular and intramuscular coordination, preventing larger scale injuries.
Plyometric exercises can be divided into two categories: low and high exercise intensity. Size intensity depends on the number of jumps, the type of jumps, amplitude, frequency, rebounds, etc.
The intensity depends on the dosage load – with low-intensity exercises, we will observe a 6-10 series with 8-10 repetitions. With high-intensity exercises, we would suggest a smaller number of series, such as 3-5, with a similar number of repetitions; 8-10 reps.
Principles of Plyometric Training
The core principles of plyometric training are as follows:
- Requires a certain level of general fitness.
- Not recommended before the age of 12, with the exception of professional assessments having been completed.
- Should occur in micro cycles (in one week) with the maximum cycle as 2-3 plyometric training programs.
- Between two training sessions, 48-72 hours of rest is required.
- The athlete must have a maximal contraction.
- Should not be combined with technique training, “deep jump” training or maximum strength training in the same session.
- Should focus on the correct technique of performing jumps and landing techniques (depreciation must be as short as possible).
- Optimal height for ‘deep jumps’ is 0.5 – 1.2 meters
- Vertical and horizontal linked jumps over a hurdle and speed training is permitted.
Combining plyometric exercised with external load is preferable. This contains post-activation potential and allows for the use of transmutation. To elaborate, Post-Activation Potentiation (PAP) heavily depends on the individual and presents acute excitation of the Central Nervous System (CNS). After implementation of a large external load, the next muscular action will be improved because of the temporary stimulation of the neuromuscular system (Ebben et al., 2000, French et al., 2003). Thus, we can conclude that this displays an acute physiological adaptation.
For instance, a “Superset”, or Training method, consists of large and small loads within the series. A Russian complex is an example of this type of method.
A rear squat (2-3 series x 2 reps), with 90% of 1RM, and a break of 2-6 minutes followed by drop jumps (2-3 sets x 8-10 reps).
The whole complex is repeated 2-3 times with breaks in between the exercises of 8-10 minutes.
In the pre-competitive and competitive period, it is preferable to preload exercises with an external load in movement exercises that will run during jumping activities. The higher load causes a later version of explosive movement and positive effects on the development of just speed-strength abilities, which are essential for many different sports.
Transmutation consists of preloading and turning the stimulus, with an aims to improve the performance of higher-level training occurring without major rest intervals. Preloading can be done in isometric, concentric and eccentric modes. The eccentric-concentric cycle can consist of slow, moderate or fast performance and is depended on the load quality. As such, the training includes the performance of specific movements after preload.
Preloading can be divided into two areas:
- Basic first preload → non-specific kinetic and kinematic parameters that provide PAP effect.
- Functional preload → close kinetic parameters for specific exercises or movements.
Preloading (basic stimulus) + preloading (functional stimulus) + turning stimuli (specific movement in normal or difficult conditions).
The use of specific and non-specific exercises, as well as the quantity and intensity of plyometric jumps in training, depends on the period of the annual cycle and fitness level of training athlete.
Plyometric training is highly beneficial for the prevention of injuries. This training leads to improvement of neuromuscular coordination, as well as the strengthening of critical zones of the locomotor system. Plyometric training also influences the development of power and speed, which are immensely important for success in many sports. It can be concluded that plyometric training should have a place in the short-term and long-term preparation of athletes.