Basics of Plyometrics and program designing.
What are plyometrics?
Plyometric exercise refers to those activities that enable a muscle to reach maximal force in the shortest
possible time. Plyometric is a combination of Greek words that literally means to increase measurement
(plio = more; metric = measure).
Plyometric is a Quick and powerful exercise using a pre- stretch, or countermovement, that involves the
stretch– shortening cycle (SSC ).
- Purpose of using Plyometrics
To increase power of subsequent movements by using natural elastic component of tendon and muscle
and the Strech reflex.
Elastic Energy- in musculotendinous component is increased with a rapid stretch and then stored followed
by a concentric muscle action, the stored energy is released increasing the total force production.
Neurophysiological Model Involves –POTENTIATION of concentric muscle action by the use of Strech Reflex.
What is a stretch Reflex?
Body’s involuntary response to an external stimulus that stretches the muscle. reflexive component of
plyometric exercise is primarily composed of muscle spindle activity
Muscle Spindle When a quick stretch is detected, muscular activity reflexively increases. During plyometric exercises, the
muscle spindles are stimulated by a rapid stretch, causing a reflexive muscle action. This reflexive
response potentiates, or increases, the activity in the agonist muscle, thereby increasing the force the
muscle produces. Both mechanical and neurophysiological contribute to the increased force production.
Most important factor in Plyometrics – Stretch Shortening Cycle (SSC)
Stretch shortening cycle - energy storage capabilities of the SEC and stimulation of the stretch reflex to
facilitate a maximal increase in muscle recruitment over a minimal amount of time. SEC stores elastic
energy, and the muscle spindles are stimulated. As the muscle spindles are stretched, they send a signal to
the ventral root of the spinal cord via the Type Ia afferent nerve fibers.
Three Phases of SSC. 1. Eccentric phase, 2- Amortization phase, 3Concentric phase.
Note* Shorter the Amortization phase Greater the force is produced.
If the amortization phase lasts too long, the energy stored during the eccentric phase dissipates as heat,
and the stretch reflex will not increase muscle activity during the concentric phase.
The rate of musculotendinous stretch is vital to plyometric exercise. A high stretch rate results in greater
muscle recruitment and activity during the SSC concentric phase.
The stretch–shortening cycle combines mechanical and neurophysiological mechanisms and is the basis of
plyometric exercise. A rapid eccentric muscle action stimulates the stretch reflex and storage of elastic energy,
which increase the force produced during the subsequent concentric action.
Program Designing for the Plyometrics.
Plyometric exercise prescription is similar to resistance and aerobic exercise prescriptions
Mode, intensity, frequency, duration, recovery, progression, and a warm-up period must all be included in
the design of a sound plyometric training program.
Before designing the program, it's very important to know about the athletes' training status, training
experience, injury, previous program etc. - NEED ANALYSIS.
Programing plyometric for athletes also depends on the athlete's game position whether they are
offensive/defensive linemen etc.
i.e you cannot program a 1.5 mile for the linemen whose work mostly lasts for only 3-5 sec. Mainly
pushing and blocking.
By understanding each sport’s individual requirements, the positions within the sport, and of the needs of
each athlete, the strength and conditioning professional is better able to design a safe, effective plyometric
training program.
MODEUpper body plyometric
Lower body Plyometric.
Lower body Plyometric includes mostly -
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Jump in place.
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involve jumping and landing in the same spot. Jumps in place emphasize the vertical component of jumping and are
performed repeatedly, without rest between jumps; the time between jumps is the stretch–shortening cycle’s
amortization phase. Examples of jumps in place include the squat jump and tuck jump
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Broad jump.
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Vertical- static/counter-movement jump.
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Depth/drop jumps
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Hops. ---
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Bounds etc.
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Bounding drills involve exaggerated movements with greater horizontal speed than other drills. Volume for bounding
is typically measured by distance but may be measured by the number of repetitions performed. Bounding drills
normally cover distances greater than 98 feet (30 m) and may include single- and double-leg bounds in addition.
Lower body plyometric give players the chance to produce more force in the shortest amount of time.
Thereby allowing higher jump.
Upper Body Plyometrics Rapid, powerful upper body movements are requisites for several sports and activities, including baseball,
softball, tennis, golf, and throws in track and field (i.e., the shot put, discus, and javelin).
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Plyometrics for the upper body include
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medicine ball throws,
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catches,
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several types of push-ups.
INTENSITY Plyometric intensity is the amount of stress placed on the involved muscles, connective tissues, and joints
and is controlled primarily by the type of drill performed. The intensity of plyometric drills covers a large
range; skipping is relatively low in intensity, while depth jumps place high stress on the muscles and
joints.
FREQUENCY – Number of plyometric `sessions per week.
Ranges from one to three depending on the sport, athletes experience with plyo training and year of
training. plyometric frequency may vary depending on the demands of the given sport, intensity and
volume of daily workouts.
Volume- MOST IMPORTANT TOPIC/FACTOR IN PLYO PROGRAM
Volume= number of foot to ground contact. typically expressed as the number of repetitions and sets
performed during a given training session.
Ranges from 80-140.
Depending upon the experience and status of athletes.
PROGRAM LENGTH – normally Ranges from 6-10 weeks
RECOVERY – Complete 48-72 hrs.
Recovery for depth jumps
Between Set
2-3 minutes
Between Reps
5-10 sec
The time between sets is determined by a proper work-to-rest ratio (i.e., 1:5 to 1:10) and is specific to the
volume and type of drill being performed.
STEPS FOR IMPLEMENTING PLYOMETRIC TRAINING PROGRAM
1.Evaluate the athlete, including the athlete’s sport and training history.
2. Establish sport-, position-, and athlete-specific goals.
3. Assign proper plyometric training program design variables, addressing intensity, frequency, recovery, volume, and
program length.
4. Teach the athlete proper jumping, landing, and throwing technique.
5. Properly progress the plyometric training program.
PROGRESSION Plyometrics is a form of resistance training and thus must follow the principles of progressive overload.
Progressive overload is the systematic increase in training frequency, volume, and intensity in various
combinations. Typically, as intensity increases, volume decreases.
WARM- UP
The specific warm-up for plyometric training should consist of low-intensity, dynamic movements.
REFRENCE – Essentials of strength and conditioning 4th edition Nsca-