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Speed and strength are integral components of fitness found in varying degrees in virtually all athletic movements. Simply put the combination of speed and strength is power. For many years, coaches and athletes have sought to improve power in order to enhance performance. Throughout this century and no doubt long before, jumping, bounding and hopping exercises have been used in various ways to enhance athletic performance. In recent years, this distinct method of training for power or explosiveness has been termed plyometrics. Whatever the origins of the word the term is used to describe the method of training that seeks to enhance the explosive reaction of the individual through powerful muscular contractions because of rapid eccentric contractions.



Muscle Mechanism

The maximum force that a muscle can develop is attained during a rapid eccentric contraction. However, it should be realised that muscles seldom perform one type of contraction in isolation during athletic movements. When a concentric contraction occurs (muscle shortens) immediately following an eccentric contraction (muscle lengthens) then the force generated can be dramatically increased. If a muscle is stretched, much of the energy required to stretch it is lost as heat, but some of this energy can be stored by the elastic components of the muscle. This stored energy is available to the muscle only during a subsequent contraction. It is important to realise that this energy boost is lost if the eccentric contraction is not followed immediately by a concentric contraction. To express this greater force the muscle must contract within the shortest time possible. This whole process is frequently called the stretch shortening cycle and is the underlying mechanism of plyometric training.

Choose the method to fit the sport

The golden rule of any conditioning program is specificity. This means that the movement you perform in training should match, as closely as possible, the movements encountered during competition. If you are rugby player, practicing for the line out or a volleyball player interested in increasing vertical jump height, then drop jumping or box jumping may be the right exercise. However if you are a javelin thrower aiming for a more explosive launch, then upper body plyometrics is far more appropriate.

Plyometric Exercises

The following are examples of lower body and upper body plyometric exercises.

Lower Body

Drop Jumping

This exercise involves the athlete dropping (not jumping) to the ground from a raised platform or box, and then immediately jumping up. The drop down gives the pre-stretch to the leg muscles and the vigorous drive upwards the secondary concentric contraction. The exercise will be more effective the shorter the time the feet are in contact with the ground. The loading in this exercise is governed by the height of the drop that should be in the region of 30 to 80 cm. Drop jumping is a relatively high impact form of plyometric training and would normally be introduced after the athlete had become accustomed to lower impact alternatives, such as two-footed jumping on the spot.

Bounding and hurdling

If forward motion is more the name of your game, try some bounding. This is a form of plyometric training, where over sized strides are used in the running action and extra time spent in the air. Two-legged bounds reduce the impact to be endured, but to increase the intensity one legged bounding, or hopping, can be used. Bounding upstairs is a useful way to work on both the vertical and horizontal aspects of the running action. Multiple jumps over a series of obstacles like hurdles are valuable drills for athletes training for sprinting or jumping events.

Examples of lower body plyometric exercises with intensity level:

Standing based jumps performed on the spot (low intensity) - Tuck Jumps, Split Jumps
Jumps from standing (low-medium intensity) - Standing long jump, Standing hop, Standing jump for height
Multiple jumps from standing (medium intensity) - bounds, bunny hops, double footed jumps over low hurdle, double footed jumps up steps
Multiple jumps with run in (High intensity) - 11 stride run + 2 hops and a jump into sandpit, 2 stride run in + bounds
Depth jumping (high-very high intensity) - jumps down and up off box (40 to 100cm), bounding up hill
Eccentric drop and hold drills (high-very high intensity) - hop and hold, bound/hop/bound/hop over 30 metres (athletes stop and hold on each landing before springing into the next move), drop and hold from a height greater than one metre
Examples of lower body plyometric exercises are detailed on the Leg Plyometric page.

Upper Body

A variety of drills can be used to make the upper body more explosive:

Press ups & hand clap: Press-ups with a hand clap in between is a particularly vigorous way to condition the arms and chest. The pre-stretch takes place as the hands arrive back on the ground and the chest sinks, and this is followed quickly by the explosive upwards action. Once again, to get the best training effect keep the time in contact with the ground to a minimum.

Medicine Ball: Another means of increasing upper body strength popular with throwers is to lie on the ground face up. A partner then drops a medicine ball down towards the chest of the athlete, who catches the ball (pre-stretch) and immediately throws it back. This is another high-intensity exercise and should only be used after some basic conditioning.

Planning a Plyometric Session

The choice of exercises within a session and their order should be planned. A session could:

begin with exercises that are fast, explosive and designed for developing elastic strength (low hurdle jumps; low drop jumps)
work through exercises that develop concentric strength (standing long jump; high hurdle jumps)
finish with training for eccentric strength (higher drop jumps)
An alternative session could be:

begin with low hurdle jumps
progress to bounding and hopping,
continue with steps or box work
finish with medicine ball work out for abdominals and upper body

Warm up

A thorough warm up is essential prior to plyometric training. Attention should be given to jogging, stretching (dynamic), striding and general mobility especially about the joints involved in the planned plyometric session. A cool down should follow each session.

How many?

It is wise not to perform too many repetitions in any one session and since it is a quality session, with the emphasis on speed and power rather than endurance, split the work into sets with ample recovery in between. An experienced athlete conducting lower body plyometrics may conduct up to 150-200 contacts in a session - athletes new to plyometric work should start with around 40 contacts per session e.g. 3 sets of 10 bunny hops is 30 contacts. Similar approach should be taken with upper body plyometrics.

The focus must always be on quality and not quantity.

Where to do it and what to wear

For bounding exercises use surfaces such as grass or resilient surfaces. Avoid cement floors because there is no cushioning. Choose well-cushioned shoes that are stable and can absorb some of the inevitable impact. All athletes should undergo general orthopaedic screening before engaging in plyometric training. Particular attention should be given to structural or postural problems that are likely to predispose the athlete to injury.

Conditioning for plyometrics

Higher than normal forces are put on the musculoskeletal system during plyometric exercises so it is important for the athlete to have a good sound base of general strength and endurance. Most experts state that a thorough grounding in weight training is essential before you start plyometrics. It has been suggested that an athlete be able to squat twice their body weight before attempting depth jumps. However, less intensive plyometric exercises can be incorporated into general circuit and weight training during the early stages of training to progressively condition the athlete. Simple plyometric drills such as skipping, hopping and bounding should be introduced first. More demanding exercises such as flying start single-leg hops and depth jumps should be limited to thoroughly conditioned athletes.


Summary

Plyometric type exercises have been used successfully by many athletes as a method of training to enhance power. In order to realise the potential benefits of plyometric training the stretch-shortening cycle must be invoked. This requires careful attention to the technique used during the drill or exercise. The rate of stretch rather than the magnitude of stretch is of primary importance in plyometric training. In addition, the coupling time or ground contact time must be as short as possible. The challenge to you as coach or athlete is to select or create an exercise that is specific to the event and involves the correct muscular action. As long as you remember specificity and to ensure there is a pre stretch first then the only limit is your imagination.

Plyometric exercise and weight training can be combined in complex training sessions to develop explosive power.


Arm Plyometrics

This following are a selection of plyometric exercises designed to develop the elastic strength of the upper body.

Chest Pass

How to perform the drill

This drill requires a partner

Stand facing each other with your feet shoulder width apart and your knees slightly bent
Begin by holding the medicine ball with both hands at chest level, elbows pointing out
Pass the ball to your partner, pushing it off your chest and ending with your arms straight
Your partner catches the ball, allows the ball to come to the chest before passing it back to you
Try to anticipate the catch and return the ball as quickly as you can
Keep the catch time to the shortest time possible

How much

1 to 3 sets
Allow a full recovery between each set
10 to 20 repetitions/set
Quality of Chest Passes is far more important than quantity

Power Drop

How to perform the drill

This drill requires a partner
Lie supine on the ground with your arms outstretched
Your partner stands on the box holding the medicine ball at arm's length
Your partner drops the medicine ball into your hands.
Catch the ball with elbows bent
Allow the ball to come towards your chest
Extend the arms to propel the ball back to the partner on the box
Keep the catch time to the shortest time possible

How much

1 to 3 sets
Allow a full recovery between each set
10 to 20 repetitions/set
Quality of the vertical toss is far more important than quantity
Incline Push up depth jump


How to perform the drill

Two mats, three to four inches high, placed shoulder width apart
A box high enough to elevate your feet above your shoulders when in a push-up position
Face the floor as if you were going to do a push-up, with your feet on the box and your hands between the mats
Push off from the ground with your hands and land with one hand on each mat
Push off the mats with both hands and catch yourself in the starting position
Keep the catch time to the shortest time possible

How much

1 to 3 sets
Allow a full recovery between each set
10 to 20 repetitions/set
Quality of Push Ups is far more important than quantity
Incline Chest Pass


How to perform the drill

Work with a partner and sit facing each other
Lean back at a 45 degree angle, keeping your abdominals tight
Begin by holding the medicine ball with both hands at chest level, elbows pointing out
Pass the ball to your partner, pushing it off your chest and ending with your arms straight
Your partner catches the ball, allows the ball to come to the chest before passing it back to you
Try to anticipate the catch and return the ball as quickly as you can
Keep the catch time to the shortest time possible

How much

1 to 3 sets
Allow a full recovery between each set
10 to 20 repetitions/set
Quality of Chest Passes is far more important than quantity

Vertical Toss


How to perform the drill

This drill requires a partner
Sit in front of the box with your back to it, legs spread apart and straight
The other person stands on the box holding the medicine ball over you
Your partner drops the medicine ball into your hands
Catch the ball with elbows bent and toss it back over your head to the partner on the box
Keep the catch time to the shortest time possible

How much

1 to 3 sets
Allow a full recovery between each set
10 to 20 repetitions/set
Quality of the vertical toss is far more important than quantity
Catch and throw backhand

Develops the external rotators

How to perform the drill

This drill requires a partner
Stand with your feet shoulder width apart, with a stable base and a good posture
Bend your right arm to 90 degrees and tuck your elbow into your side
Keep your trunk facing forward
Rotate the right arm out ready to catch the ball
Your partner stands to your right and throws a small ball (1kg) to your right hand
You catch it, then quickly take the ball across your body rotating your right arm inwards, and the immediately throw the ball back, powerfully rotating the right arm out.
Do not use your trunk and keep your right elbow into your side at all times.
Concentrate the effort on your right rear shoulder and external rotator muscles
Repeat for the left arm with your partner standing on your left side

How much

1 to 3 sets
Allow a full recovery between each set
10 to 20 repetitions/set
Quality of the throw is far more important than quantity

Leg Plyometrics

The following are some examples and explanations of leg plyometric exercises.

Bounds


How to perform the drill

Jog into the start of the exercise
Push off with your left foot and bring the leg forward, with the knee bent and the thigh parallel to the ground
At the same time, reach forward with your right arm. As the left leg comes through, the right leg extends back and remains extended for the duration of the push-off
Hold this extended stride for a brief time, then land on your left foot
The right leg then drives through to a forward bent position, the left arm reaches forward, and the left leg extends backward
Make each stride long, and try to cover as much distance as possible
You should land on the sole of the foot (flat footed), allowing energy to be stored by the elastic components of the leg muscles, and immediately take off again
Keep the foot touch down time to the shortest time possible

How much

One to three sets over 30 to 40 metres
Allow a full recovery between each set
Quality of bounding is far more important than quantity.

Hurdle Hopping


How to perform the drill

Jump forward over the barriers with your feet together
The movement should come from your hips and knees
keep your body vertical and straight, and do not let your knees move apart or to either side
Tuck both knees to your chest
Use a double arm swing to maintain balance and gain height
You should land on the balls of the feet, allowing energy to be stored by the elastic components of the leg muscles, and immediately take off again
Keep the feet touch down time between hurdles to the shortest time possible

How much

One to three sets using 6 to 8 hurdles
Allow a full recovery between each set
Hurdles should set up in a row, spaced according to ability
The height of the hurdles should be in the region of 12 and 36 inches high
Quality of hurdle hopping is far more important than quantity

Step Training Hurdles

Excellent for agility, plyometric and sprint drill training. Available in 6 inch, 9 inch and 12 inch heights.
Select this link to order your Step Training Hurdles.

Single Leg Hopping


How to perform the drill

Stand on one leg
Push off with the leg you are standing on and jump forward, landing on the same leg
Use a forceful swing of the opposite leg to increase the length of the jump but aim primarily for height off each jump
You should land on the ball of the foot, allowing energy to be stored by the elastic components of the leg muscles, and immediately take off again
Keep the foot touch down time to the shortest time possible
Try to keep your body vertical and straight
Perform this drill on both legs
Beginners will use a straighter leg action where as advanced athletes should try to pull the heel toward the buttocks during the jump

How much

One to three sets over 30 to 40 metres
Allow a full recovery between each set
Quality of bounding is far more important than quantity
Box Jumps


How to perform the drill

Assume a deep squat position with your feet shoulder width apart at the end of the row of boxes
Keep your hands on your hips or behind your head
Jump onto the box, landing softly in a squat position on the balls of the feet
Maintaining the squat position, jump off the box onto the ground, landing softly in a squat position on the balls of the feet
Jump onto the next box and so on
Keep the feet touch down time on the ground to the shortest time possible
How much

One to three sets using 6 to 8 boxes
Allow a full recovery between each set
The height of the box should be in the region of 30-80 cm
Quality of box jumping is far more important than quantity

Depth Jumps


How to perform the drill

Stand on the box with your toes close to the front edge
Step from the box and drop to land on then balls of both feet
Try to anticipate the landing and spring up as quickly as you can
Keep the feet touch down time on the ground to the shortest time possible

How much

One to three sets using 6 to 8 boxes
Allow a full recovery between each set
The height of the box should be in the region of 30-80 cm
Quality of depth jumping is far more important than quantity


Tuck Jumps


How to perform the drill

Begin in a standing position
Jump up, grabbing both knees as they come up your chest
Return to the starting position landing on the balls of the feet
Try to anticipate the landing and spring up as quickly as you can
Keep the feet touch down time on the ground to the shortest time possible

How much

1 to 3 sets
Allow a full recovery between each set
5 to 10 repetitions/set
Quality of Tuck Jumps is far more important than quantity
Two legged Hops or Bunny Hops


How to perform the drill

Stand with your feet shoulder-width apart
Lower into a squat position and jump as far forward as possible
Land on the balls of both feet
Try to keep your body vertical and straight, and do not let your knees move apart or to either side
Try to anticipate the landing and spring up as quickly as you can
Keep the feet touch down time on the ground to the shortest time possible
Use quick double-arm swings and keep landings short

How much

1 to 3 sets
Allow a full recovery between each set
5 to 10 repetitions/set
Quality of Bunny Hops is far more important than quantity




Brain MacKenzie