OVERVIEW VIEWPOINT© by IAAF Plyometric Training 27:3; 9-21, 2012 and the High Jump by Jürgen Schiffer • Integration of plyometric training in the athlete’s training programme, AUTHOR • Practical aspects of plyometric training, • Plyometrics and resistance training, Jürgen Schiffer, PhD, is the Vice-Director • Plyometrics and circuit training, of the Central Library of the German Sport • Plyometric drills, University in Cologne and the Documenta- • Plyometrics and the high jump. tion Editor of NSA. The History of Plyometric Training Introduction Although western training scientists be- came aware of plyometrics in the mid-1970s, this form of training was developed in the Sovi- lyometric training is an important ele- et Union in the 1950s and early 1960s (DUKE, ment of the training programme of most 1990). The term was initially synonymous with P top-level jumpers, including high jump- triple jumpers and triple jump training (see, for ers. Although it has developed over more than example, YOUNG & MARINO, 1985). To de- half a century and been reported in the literature, velop the type of loads that the plant leg had its proper utilisation is still not fully understood by to withstand in the hop and step phases, ath- many coaches. Some apply plyometrics incor- letes trained by jumping down from one box rectly, which can reduce the positive training ef- onto the plant leg and instantly jumping up fects or even lead to injuries, while others avoid onto another box. The terms “stretch-shorten- the means, and thus compromise the potential ing” training, “depth jump” training, “reactive” performances of their athletes. training, “drop jump” training and “eccentric- concentric” training started appearing in the The aim of this article is to address this literature more and more in the 1960s. situation by providing a summary of the main aspects of plyometric training, drawn from the A particularly important piece of literature at current literature, as a general guide and as a the time was a study by Verhoshanski (1967), starting point for further study and discussion. where he advocated depth-jump heights be- Special emphasis is given to the use of plyo- tween 0.75 and 1.15m. According to REID metrics in training for the high jump. (1989), many coaches took this to mean ath- The main points to be covered are: letes could develop the stretch reflex by jump- ing down from boxes higher and higher, land • The history of plyometric training, on pre-stretched plant leg and bound back up • The scientific basis of plyometric training, onto another box. Such training was not sub- • Plyometric training compared to traditional stantiated by scientific research and the injury resistance training and ballistic training, score increased. However, over-zealous coach- New Studies in Athletics · no. 3.2012 9 Plyometric Training and the High Jump es often rationalised that athletes who could not The Scientific Basis of Plyometric complete the drill were simply too weak. Training Valeriy Borzov’s (URS) double victory in the During plyometric, or stretch-shortening, sprints at the 1972 Olympic Games in Munich exercises the muscle is rapidly stretched (ec- 1972 made everyone aware of how plyometrics centric contraction) and then shortened to can be incorporated into a sprint training pro- accelerate the body upward, as in a counter- gramme. Borzov made extensive use of vari- movement jump (see Figure 1). ous jumping exercises in his training but was by no means the first sprinter to utilise plyometric training. Armin Hary (FRG), the 100m gold med- allist in the 1960 Olympics, made use of various jumping exercises throughout his training pro- gramme. Many sprinters have also participated in the long jump, the training for which serves a similar purpose. A good example is Irena Sze- winska (POL), the multiple Olympic medallist, who incorporated extensive jump training into her programme (GAMBETTA, 1987). However, plyometric training has by no means been the exclusive domain of the sprint- ers/jumpers. Throwers, too, have used plyo- metrics, both for the upper and lower body. Upper body plyometrics has mainly taken the form of medicine ball exercises using 3-6kg Figure 1: Countermovement jump (Hoffman, 2002) balls. Janis Lusis (URS), former javelin world record holder and Olympic champion, made This stretch-shortening cycle has been dem- extensive use of jump training in the form of onstrated to enhance power performance to a hurdle jumps, hopping, and bounding to de- greater extent than concentric training only (e. velop the explosive power in his legs. g. by performing squat jumps) (Bosco, Vii- tasalo, Komi & Luhtanen, 1982). The im- Plyometric type training has also been utilised proved performance seen in the countermove- in the realm of middle distance and distance ment jump is attributed to a greater amount of training. Hill bounding, advocated by Arthur Lyd- stored elastic energy acquired during the ec- iard in the late 1950s, was designed to yield a centric phase that is able to be recruited during powerful stride but is nothing more than bound- the upward movement of the jump (Bosco & ing with the added resistance of the hill. Pekka Komi, 1979). In addition, the pre-stretch during Vasala (FIN), the 1972 Olympic champion over the countermovement results in a greater neural 1500m, used a six-week period of a ‘bounding stimulation (Schmidtbleicher, Gollhofer endurance phase’ in his training. This was per- & Frick, 1988) as well as an increase in the formed up a 400m slope of 5-15° gradient. joint moment (a turning effect of an eccentric force, also referred to as torque at the start of All these examples show that plyometric the upward movement (Kraemer & Newton, training in itself is not new, but the proper appli- 2000)). The greater joint moment results in a cation as a training method needs further clari- greater force exerted against the ground with a fication and guidelines (GAMBETTA, 1987). subsequent increase in impulse (greater force applied over time) and acceleration of the body upward. BOBBERT et al. (1996) have suggested that this latter mechanism may be the primary 10 New Studies in Athletics · no. 3.2012 Plyometric Training and the High Jump reason for the greater jump height observed dur- 1. The primary training method has used tra- ing a countermovement jump, whereas the other ditional resistance training programmes mechanisms may play more of a secondary role. with a relatively high intensity of training (4-6 RM) performed at a relatively slow ve- The performance of a stretch-shortening cycle locity of movement. requires a finely coordinated action of agonist, antagonist, and synergistic muscle groups. 2. Plyometric training is another training During the rapid action of the stretch-shorten- method that is used to enhance power ing cycle, the agonist and synergistic muscle performance. Most plyometric exercises groups must apply a great deal of force in a require the athletes to rapidly accelerate relatively short period of time. To maximise and decelerate their body weight during this action, the antagonist muscle groups a dynamic movement. The athletes’ body must be relaxed during the time the agonists weight is most often used as the overload, and synergists are active. However, a nov- but the use of external objects such as ice to stretch-shortening movements needs medicine balls also provides a good training some training to coordinate these movements. stimulus for certain plyometric exercises. Through training, contraction of the antagonist muscle muscle groups is reduced, which al- 3. The final method of training to enhance lows for a greater coordination of these muscle muscular power and explosive sports perfor- groups and produces a more powerful and ef- mance is a combination of traditional re- fective vertical jump. In addition, during the ini- sistance training and plyometric training. tial workouts, the EMG (electrical activity of the This form of resistance training is referred exercising muscles, indicating extent of activa- to as ballistic training. Ballistic movements tion) of the agonist muscle groups appears to (see Figure 2) are forced movements initi- be reduced. This is likely the result of activation ated by muscle actions but continued by of the golgi tendon organ (a muscle proprio- the momentum of the limbs (KENT, 2006). ceptor) to protect the muscle from excessive Ballistic movements are performed at a stretch. As the training programme continues, much lower intensity of training (approxi- these inhibitory effects exhibited by the muscle mately 30% of 1 RM) using a much higher proprioceptors may be reduced, allowing for velocity of movement (Wilson, Newton, improved stretch-shortening perform-ance Murphy & Humphries, 1993). The have (Schmidtbleicher et al, 1988). three main phases: 1) an initial phase of concentric action that starts the move- The primary question when discussing plyo- ment, 2) a coasting phase that relies on the metric training is whether plyometric drills should momentum generated in the initial phase, be considered a supplement to the normal train- and 3) a deceleration phase accompanied ing regimen or an alternative way of training. Spe- by eccentric actions (KENT, 2006). cifically, will plyometric training itself be as effec- tive in improving power and strength performance as resistance training? Will including these drills as part of the overall training programme provide any additional benefit for the athlete? Plyometric Training Compared to Traditional Resistance Training and Ballistic Training Three methods of training are generally used to improve the power of athletes who participate in dynamic, explosive sports: Figure 2: Ballistic training (HOffMAN, 2002) New Studies in Athletics · no. 3.2012 11 Plyometric Training and the High Jump Studies have demonstrated the effective- Integration of Plyometric Training in ness of plyometric training for improving pow- the Athlete’s Training Programme er, generally expressed as increases in vertical jump height (e.