Plyometric and Speed Training: Part A

Plyometric and Speed Training: Part A Explosion and Power

Introduction • In terms of performance…athletes are always looking for advantages to put them over the top • Use of plyometrics and speed training has been used to develop that advantage for most sports involving explosive and powerful movements • Plyometrics and speed training have become important in increasing ability of athletes to better control deceleration forces, which can contribute to athletic injury

Introduction • Plyometric Exercise: quick, powerful movements preceded by a pre-stretch or counter-movement followed by an immediate powerful concentric muscle action • Speed: the ability to achieve a high velocity • The purpose of the plyometric and speed training is to elicit the SSC to achieve increased power in important athletic movements • Speed training essential works to do the same thing, but also adds in technique and muscular strength to produce larger ground forces, which allows clients to run faster

Plyometric Mechanics and Physiology • Power: term used to describe the force-velocity relationship • When done correctly…plyometric exercise can effectively improve muscle force and power • Increased power production can be explained in two ways: • Mechanical and Neurological

Plyometric Mechanics and Physiology • Mechanical Model of Plyometric Exercise • Elastic energy is stored following a rapid stretch and then released during the concentric muscle action…this then increase muscle force production • Series Elastic Component (SEC) is a major contributor to force production…it includes some muscle, but it mainly tendon • When the musculotendinous unit is stretched during eccentric muscle action…the SEC acts like a coiled spring to store elastic energy • Once and if immediate concentric action happens the stored energy will be released to create increased force production • If there is no immediate concentric action then the energy is wasted and lost as heat

Plyometric Mechanics and Physiology • Neuro-physiological Model of Plyometric Exercise • This element involves a change in the force-velocity characteristics of a muscle contractile elements • Concentric muscle action is enhanced through the stretch reflex mechanism • This is an involuntary response by muscles • Muscle spindles involved are sensitive to time and rate of stretch • Muscle spindles detect stretch and cause increased muscle activity • Just like the mechanical model, if not used immediately then the increased muscle activity dissipates and the muscle relaxes due to Golgi tendon organs kicking in (this is ideal for stretching!)

Plyometric Mechanics and Physiology • Stretch Shortening Cycle • Simply put: • Eccentric phase(deceleration phase) • Muscle put on a stretch, preloading the agonist muscle group • Stores elastic energy for use in the concentric phase • Amortization phase • Time between eccentric and concentric phases (end of eccentric to beginning of concentric phase) • Phase must be kept in short duration for positive effects on force production to take place (stored energy lost as heat if not immediately used) • Concentric phase • Muscle group action occurs causing release of stored elastic energy from SEC • Increased muscle force production • Not effective if amortization phase is held too long (energy lost as heat)

When to Use Plyometric Exercise • Plyometric Training and Sport Performance • Increased muscular power is an important and necessary characteristics of most athletes and relates to positive performance results • Ideal for trying to improve muscle force production • Prepares athletes for deceleration-acceleration and change in direction requirements for athletic tasks • Running economy improved as well in average-distance runners

When to Use Plyometric Exercise • Plyometric Training and Work Performance • There is some evidence that plyometric training can be important for work performance • Police officers • Firefighters • Individuals preparing for the military • All these professions must be able to run quickly, change direction effectively, and jump onto or over objects to perform their occupational duties

When to Use Plyometric Exercise • Plyometric Exercise and Injury Prevention • Studies have shown that athletic injury rate is decreased following use of plyometric training programs • Improves bone mineral content, muscle recruitment, strength, body control, and balance • However, it has been difficult to generalize these results to other populations • Eccentric training may be a compromise for clients who wish to engage in injury prevention activities but for whom plyometric training is not appropriate.

When to Use Plyometric Exercise • Contraindicated Populations • Age • Plyometrics are safe and beneficial for youth, as soon as a client is mature enough to accept and follow directions. • Be mindful of high-intensity lower body plyometrics due to the epiphyseal plates of prepubescent children still being open • Plyometrics are appropriate for adolscents • Use low-intensity drills if all safety conditions have been met • Older clients should avoid high-intensity plyometrics, but low to moderate plyometrics can be continued on an individual basis • Physical maturity is not the sole determinant of plyometric predaredness.

When to Use Plyometric Exercise • Experience and Training Level • Clients who have never participated in regular resistance training programs should be prohibited from participating in plyometric exercises • Plyometric programs require a significant amount of strength and neurological functioning so encourage starting a regular resistance training program first

Posture, Flexibility, and Stability • A solid base of support is necessary for the traditional and non-traditional movement patterns used in plyometric training. • The partial or half-squat position is: • Chin tucked in slightly • The scapulae are slightly retracted • The trunk is parallel to the tibias • Knees are directly over or slightly posterior to the toes, and heels should remain on the ground. • Once the client can hold the position above progress to the bodyweight squat

Posture, Flexibility, Stability • Once the client can hold a proper double-leg squat position and perform a proper body weight squat, they may begin low-intensity plyometric exercises. • They must learn to maintain the proper alignment, providing a strong base for dynamic action.

Posture, Flexibility, and Stability • Before increasing the level of plyometric exercises, the client should be able to hold a single-leg squat position as described for the balance tests shown in table 17.2, pg. 417 • Each test position must be held for 30 seconds

Strength • Before adding plyometrics to a client’s workout program, the personal trainer must also take the client’s level of strength into consideration. • For lower body plyometrics, the client’s 1RM squat should be at least 1.5 times his or her body weight • For upper body plyometrics, clients weighing more than 220 pounds should have a bench press 1RM of at least 1.0 times their bodyweight; those under 220 pounds should have a bench press 1RM of at least 1.5 times their bodyweight • An alternative measure of prerequisite upper body strength is the ability to perform five clap push-ups in a row

Medical History and Physical Characteristics • Medical clearance is prudent for any client with a diagnosed condition. • Physical characteristics • Clients who weigh above 220 pounds are at increased risk and should avoid high volume plyometrics • No depth jumps greater than 18 inches tall • Plyometric exercises should be limited to those involving double-leg take offs and progress to single-leg when proficient with double-leg.

Speed • For lower body plyometrics the client should be able to perform five repetitions of a squat with 60% of body weight in 5 seconds or less • For upper body plyometrics the client should be able to perform five repetitions of the bench press with 60% bodyweight in 5 seconds or less • If the client lacks the necessary speed they may begin a low-intensity plyometric program that does not rely heavily on speed • Two-foot ankle hop, standing long jump, double leg vertical jump

Landing Position Shoulders over the knees, knees should be slightly over or slightly posterior to the toes, with the ankles, knees, and hips flexed and the feet approximately shoulder-width apart. Weight should be placed more on the ball of the foot and not the heel to facilitate quick turn around on landings and enhance control of the center of gravity

Equipment and Facilities • Landing surface • Adequate shock absorption (grass field, turf, suspended floor, rubber mats) • Hardwood, concrete, and tile are not recommended as they are not sufficiently shock absorbent • Training Area • Bounding and running require 33 yards of straightaway, and up to 109 yards • Most standing, box, and depth jumps require an area of 9.8 to 13.2 feet, but adequate height is necessary • Equipment • Boxes should have a non-slip top, be closed on all sides • Height can range from 6 to 42 inches with a landing surface of at least 18 by 24 inches

Plyometric Program Design • Needs Analysis: Evaluate the client’s current abilities before plyometric exercises begin • Age: does age predispose client to injury and therefore preclude them • Training experience or current level of training: has client been resistance training? What types of exercises has client been performing? Plyometrics before? • Injury history: currently injured? Have any previous injuries that would affect plyometric training status? • Physical testing: what are clients capabilities in relation to power production • Training goals: what does client want to improve? Particular skills • Incidence of injury in a client’s job or chosen activity: what is risk of injury in chosen activity?

Plyometric Program Design • Mode • Which kinds of plyometric exercises are appropriate based on client goals and specific sporting involvement • Lower Body • Appropriate for clients in almost any sport • Requires participants to produce maximal force in a minimal amount of time • Clients in sports like basketball would benefit greatly from lower body plyo’s due to repetitive jumping involved in the sport • Types of lower body plyo’s…depth jumps, standing jumps, bounds, box drills, etc.

Plyometric Program Design • Upper Body Plyometrics • Rapid upper body movements are required in a variety of sport such as golf, baseball, football and tennis • Not used as often, but are very effective nevertheless • Examples include…med ball throws, catches, and push up variations

Plyometric Program Design • Intensity • Refers to the amount of stress placed on the muscles, connective tissues and joints and is controlled by the type of drill performed and distance covered • Intensity ranges from low-level to high-level • Intensity should be kept low for beginners • Efforts should be geared towards technique rather than volume to help prevent injury

Plyometric Program Design • Intensity • Better to underestimate than overestimate • Youth and adolescents should begin with one or two sets of 6-8 repetitions to ensure quality reps each set

Plyometric Program Design • Frequency • Number of plyometric training sessions per week • Depends upon client’s goals • Optimal frequency is limited in terms of research • Two times per week for moderate intensity plyometrics is best • For youth: Two non-consecutive days per week is recommended

Plyometric Program Design • Recovery • Amount of time or rest between plyometric exercises • Depends upon work to rest ratio (range of 1:5 to 1:10) and is specific to volume and type of drill being performed • Higher intensity of a drill, the more rest a client requires • Rest times of 60-120 seconds between drills should allow for full or near full recovery • 48 to 72 hours between plyometric sessions is recommended

Plyometric Program Design • Volume • Typically expressed as number of repetitions and sets performed during a training session • Lower body plyo’s expressed as number of foot contacts (e.g. bounding contacts) • Upper body usually expressed as number of throws or catches • Refer to Table 17.6 (pg. 425) for volume guidelines by age and experience level

Plyometric Program Design • Progression • Plyometrics is a form of resistance training so it must adhere to principles of progression such as overload and F.I.T.T • As intensity increases, volume decreases • Landing first • Horizontal or vertical components • Double leg before single leg

Plyometric Program Design • Warm Up • Plyometric exercise should begin with general and specific warm ups • General may consist of light jogging or stationary bike, etc. • Specific would be dynamic movements similar to those in plyometric training • See Table 17.7 (pg. 426) for examples of plyometric warm up drills

Safety Considerations • Maturity • Caution with children under 14 yrs old and older than 60 yrs old • Clients must also respond positive psychologically to specific instructions

Safety Considerations • Clients must be closely monitored to ensure proper technique • Plyometric exercise once again is not inherently dangerous, but supervision helps reduce injury prevention

Plyometric and Speed Training: Part A