Identify and describe each sub-component within the three primary components of plyometrics

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PLYOMETRICS THEORY AND APPLICATION LEARNING OBJECTIVES Define plyometrics and list the three primary components Identify and describe each sub-component within the three primary components of plyometrics Describe the performance and injury prevention benefits associated with plyometrics Identify and design effective plyometric programming relative to individual differences and session demand 2 1

What should we consider when trying to optimize transfer from the weight room to sport? Strength Demands 2

Speed Demands Sport Demands 3

PLYOMETRICS: DEFINED PLYOMETRICS Shock-method was first proposed by Dr. Yuri Verkhoshansky and popularized through the use of depth/drop jumps The term PLYOMETRICS was later proposed by western track coach Fred Wilt Plyometrics represent a category of movements that are meant to improve overall speed-strength qualities 8 4

DEFINING PLYOMETRICS Drills aimed at linking optimal strength and speed during fundamental movement patterns (speed-strength) Defined as a quick, powerful movements that utilize the stretch-shortening cycle (SSC) 9 SSC is defined as a rapid muscle lengthening followed immediately by a rapid muscle shortening 10 5

SSC optimizes the use of the stretch reflex and stored elastic energy 11 PLYOMETRIC COMPONENTS MOVEMENT DIRECTION INITIATION Based on the dominant motor patterns being taught within the following Movement Skills session Based on dominant force vectors being taught within the following Movement Skills session Based on the dominant contraction types being taught within the following Movement Skills session 12 6

PLYOMETRIC: MOVEMENT JUMP Two foot take-off followed by a two-foot landing BOUND Single foot take-off followed by an opposite single foot landing HOP Single foot take-off followed by the same single foot landing 13 01 MOVEMENT (JUMP) Continuous Lin-Vert Jump Continuous Lin-Vert Box Split Jump 14 7

01 MOVEMENT (BOUND) Countermovement Lat-Horiz Bound Countermovement Lat-Horiz 45 Bound 15 01 MOVEMENT (HOP) Drop Hop (Plyo Prep) Countermovement Lin-Vert Box Hop 16 8

PLYOMETRIC: DIRECTION LINEAR Movement direction includes Linear-Vertical and Linear-Horizontal LATERAL Movement direction includes Lateral-Vertical and Lateral-Horizontal ROTATIONAL Movement direction includes Rotational-Vertical and Rotational-Horizontal 17 02 DIRECTION (LINEAR) Continuous Lin-Vert Alternating Split Jump Double Contact Lin-Horiz Hurdle Hop 18 9

02 DIRECTION (LATERAL) Countermovement Lat-Vert Box Hop Countermovement Lat-Horiz Hurdle Hop 19 02 DIRECTION (ROTATIONAL) Countermovement Rot-Vert 180 Jump Countermovement Rot-Horiz 90 Bound 20 10

PLYOMETRIC: INITIATION NON COUNTER- MOVEMENT No lengthening action prior to shortening action (Concentric only) COUNTER- MOVEMENT DOUBLE CONTACT CONTINUOUS DEPTH/DROP JUMP Rapid lengthening action prior to an immediate shortening action (SSC) Lengthening action preceded by a rapid ground contact and followed by a shortening action (SSC) Linking multiple SSC repetitions together in quick succession (SSC) Lengthening action preceded by a rapid ground contact from a box and followed by a shortening action (SSC) 21 03 INITIATION (NON-COUNTERMOVEMENT) NCM Lin-Vert Jump NCM Lin-Vert Box Split Jump 22 11

03 INITIATION (COUNTERMOVEMENT) CM Lat-Horiz Hurdle Hop-Lateral CM Lat-Horiz Hurdle Hop-Medial 23 03 INITIATION (DOUBLE CONTACT) DC Lat-Horiz Hurdle Hop-Lateral DC Lat-Horiz Hurdle Hop-Medial 24 12

03 INITIATION (CONTINUOUS) CONT Lin-Horiz Hurdle Hop-Lateral CONT Lin-Horiz Hurdle Hop-Medial 25 CHECK FOR LEARNING 01 List the 3 primary components of plyometrics and the associated 3-5 sub-components Write down 3-5 different plyometric movements using the appropriate labeling 26 13

PLYOMETRICS OPTIMIZING TRANSFER PERFORMANCE ENHANCEMENT 14

PLYOMETRICS: PRIMARY GOAL Apply optimal force (strength) and velocity (speed) in the correct direction within the shortest time (efficiency) 29 PLYOMETRICS: PERFORMANCE BENEFIT Increased explosive strength due to improved rate of force development (RFD) Increased reactive strength due to greater storage and reutilization of elastic energy Improved ability to transfer force through the joints and minimize energy leaks (Aagaard at al., 2002, Komi, 2003 and Turner and Jeffreys, 2010) 30 15

FORCE-VELOCITY RELATIONSHIP Maximal Strength 300ms Performance in Sport < 250ms High Speed Running < 100ms MAXIMAL STRENGTH SPEED STRENGTH SPEED Force (N) PLYOMETRICS Time (s) (Newton & Kraemer, 1994) Velocity (M/S) 31 RATE OF FORCE DEVELOPMENT Heavy resistance training Explosive plyometric training Force (N) Untrained RFD 0 200ms 500ms (Newton & Kraemer, 1994) 32 16

What are the mechanisms underpinning the performance benefit of plyometrics? Stretch-Shortening Cycle (SSC) STRETCH-SHORTENING CYCLE Movements utilizing a stretch-shortening cycle have been shown to increase performance by 10-15% compared to movements that do not. (Turner & Jeffreys, 2010) 34 17

SSC: MECHANISMS FORCE POTENTIATION CONTRACTILE CONTRIBUTION INCREASED ACTIVATION TIME (Blazevich, A.., 2011) STRETCH- SHORTENING CYCLE (SSC) ELASTIC CONTRIBUTION STRETCH REFLEX STORAGE OF ELASTIC ENERGY (MUSCLE) STORAGE OF ELASTIC ENERGY (TENDON) 35 SSC: CONTRACTILE Afferent Signal + Stretch Contractile Element + Parallel Elastic Component (PEC) Muscle Spindle + Stretch Reflex Efferent Signal + Contract (Modified from Hill s model for muscle contraction) 18

SSC: ELASTIC Slow SSC >250ms: -Walking -Jogging -CMJ Fast SSC <250ms: -Sprinting -Change of Direction -DC/Depth Jumps Contractile Element + Parallel Elastic Component (PEC) Tendon+ Series Elastic Component (SEC) (Schmidtbleicher, p. 381-395, 1992) (Modified from Hill s model for muscle contraction) INJURY PREVENTION 19

PLYOMETRICS: SECONDARY GOAL Decrease risk of injury through increased tolerance to stretch loads at various speeds, loads, and directions 39 PLYOMETRICS: INJURY PREVENTION BENEFIT Injuries primarily occur during unexpected over-lengthening of muscle/ligaments during landing and deceleration tasks Many of these injuries occur when an athlete finds themselves in a position for which they do not have a robust motor response Plyometrics improve an athlete s ability to handle rapid stretch loads and supports enhanced coordination of movement during reaction and rapid change of direction tasks (Myer et al., 2008, Turner & Jeffreys, 2010 and Wilson & Flanagan, 2008) 40 20

Plyometrics have been shown to improve performance factors while decreasing biomechanical risk factors associated with ACL tears Design: - Females: N=18 (F) underwent 8 weeks of plyometrics training and N=18 (F) acted as a control and did no physical activity Results: - The plyometric group improved hop based performance measures while improving lower limb kinematics during single leg movement Baldon et al., 2014 41 A 2012 Meta-Analysis showed that males and females involved in neuromuscular based ACL prevention programs including plyometrics have a significant reduction in ACL tears (M: 85%; F: 52%) Sadoghi et al., 2012 42 21

CHECK FOR LEARNING 02 List at least 3 factors that contribute to the performance improvements seen during SSC opposed to non-ssc movement (i.e. NCM Jump vs. CM Jump) Write down 3-5 sentences describing the role of plyometrics in preventing non-contact injuries (ex. ACL injury)1 43 PROGRAMMING 22

PROGRAMMING CONSIDERATIONS Frequency Volume Intensity Methods FREQUENCY, VOLUME & INTENSITY FREQUENCY VOLUME INTENSITY MOVEMENTS Weekly: 2x (15-20min) Focus: Speed-Strength Contacts: 40-60/session Total: 120/wk Sets/Reps: 2-3sets/4-6reps Rest Set/Session: 1-3min/72hrs Movements: 3-5 Directions: 1-2 Initiations: 2-3 Weekly: 4x (5-15min) Focus: Activation Contacts: 20-30/session Total: 120/wk Sets/Reps: 1-2sets/4-6reps Rest Set/Session: 1-2min/24hrs Movements: 2-3 Directions: 1-2 Initiations: 2-3 (de Villarreal et al., 2009) 23

KEY CONSIDERATION Studies on plyometrics do not factor in total training volume (ex. inclusion of strength and movement skills) and make recommendations solely based on plyometric training METHODS (EX. JUMP BOUND HOP) LINEAR VERTICAL TO HORIZONTAL LATERAL VERTICAL TO HORIZONTAL ROTATIONAL VERTICAL TO HORIZONTAL CONTINUOUS Lin-Vert Jump Lin-Horiz Bound Lat-Horiz 45 0 Bound Lat-Horiz Hurdle Hop Rot-Vert 180 0 Jump Rot-Vert 90 0 Hop INTENSITY DOUBLE CONTACT COUNTER- MOVEMENT Lin-Horiz Hurdle Jump Lin-Horiz Hurdle Hop Lin-Vert Jump Lin-Horiz Bound Lat-Horiz Bound Lat-Horiz Hurdle Hop Lat-Horiz 45 0 Bound Lat-Horiz Hurdle Hop Rot-Vert 270 0 Jump Rot-Horiz 180 0 Bound Rot-Vert 180 0 Jump Rot-Vert 90 0 Hop NON COUNTER- MOVEMENT Lin-Vert Box Jump Lin-Vert Hurdle Hop Lat-Vert Bound Lat-Vert Hurdle Hop Rot-Vert 90 0 Jump Rot-Horiz 90 0 Bound INTENSITY 24

EXAMPLE PROGRAMMING: PLYOMETRICS PLYOS: Linear Movement Skills Novice Athlete (4x per week) Movement 1: -NCM Lin-Vert Box (12in) Jump -2 x 5 repetitions Movement 2: -CM Lin-Horiz (12in) Hurdle Jump -1 x 5 repetitions Movement 3: -CM Lin-Horiz (6in) Hurdle Hop -2 x 5 repetitions each Total Contacts: 25 PLYOS: Multi- Movement Skills Advanced Athlete (2x per week) Movement 1: -CM Lat-Horiz Bound (Quick-Stick) -2 x (3x3) repetitions each Movement 2: -Continuous Lat-Horiz 45 0 Bound -2 x 5 repetitions each Movement 3: -DC Lat-Horiz (12in) Hurdle Hop -1 x 5 repetitions each (medial & Lateral) Total Contacts: 38 GUIDELINES Movement (Jump Bound Hop) - More Stable to Less Stable Direction (Linear Lateral - Rotational) - General to Specific (Vertical to Horizontal) Initiation (NCM CM DC CONT DJ) - Low Force to High Force (Progression & Continuum) Equipment (Low Box Ground Hurdle High Box) - Low Force to High Force 50 25

CHECK FOR LEARNING 03 Create a single 10 min plyometric program based on a 4x week intermediate athlete preparing for linear speed sessions (Note: Only create the plyometric portion and include as much detail on volume and intensity as possible) 51 CLOSING 26

MOVEMENT Movements are selected based on the level of athlete (2-leg to 1-leg) and the specific movement characteristics in need of development (movement skills & sport) 53 DIRECTION Movement directions are selected based on the level of athlete (linear to rotational) and the specific directional force characteristics in need of development (movement skills & sport) 54 27

INITIATION Movement initiations are selected based on the level of athlete (NCM to DJ) and the specific speed-strength characteristics in need of development (strength & movement skills) 55 28

APPENDIX Aagaard, P., Simonsen, E. B., Andersen, J. L., Magnusson, P., & Dyhre-Poulsen, P. (2002). Increased rate of force development and neural drive of human skeletal muscle following resistance training. Journal of applied physiology, 93(4), 1318-1326. Blazevich, A. (2011). The Stretch-Shortening Cycle (SSC). Strength and Conditioning: Biological principles and practical applications, 2.8, 209-221. Bobbert, M. F., Gerritsen, K. G., Litjens, M. C., & Van Soest, A. J. (1996). Why is countermovement jump height greater than squat jump height?.medicine and science in sports and exercise, 28, 1402-1412. Bosch, F., & Klomp, R. (2005). Running: Biomechanics and exercise physiology in practice. Elsevier Churchill Livingstone. Bosco, C., Montanari, G., Ribacchi, R., Giovenali, P., Latteri, F., Iachelli, G.,... & Saibene, F. (1987). Relationship between the efficiency of muscular work during jumping and the energetics of running. European journal of applied physiology and occupational physiology, 56(2), 138-143. Cardinale, M., Newton, R., & Nosaka, K. (Eds.). (2011). Strength and conditioning: Biological principles and practical applications. John Wiley & Sons. Carlock, J. M., Smith, S. L., Hartman, M. J., Morris, R. T., Ciroslan, D. A., Pierce, K. C.,... & Stone, M. H. (2004). The relationship between vertical jump power estimates and weightlifting ability: a field-test approach. The Journal of Strength & Conditioning Research, 18(3), 534-539. Chu, D. (1983). Plyometrics: The link between strength and speed. Strength & Conditioning Journal, 5(2), 20-21. 57 APPENDIX Chu, D. (1998). Jumping into plyometrics. Human Kinetics. Cormie, P., McGuigan, M. R., & Newton, R. U. (2011). Developing maximal neuromuscular power. Sports medicine, 41(1), 17-38. de Marche Baldon, R., Lobato, D. F. M., Yoshimatsu, A. P., dos Santos, A. F., Francisco, A. L., Santiago, P. R. P., & Serrão, F. V. (2014). Effect of Plyometric Training on Lower Limb Biomechanics in Females. Clinical Journal of Sport Medicine, 24(1), 44-50. Hewett, T. E., Ford, K. R., & Myer, G. D. (2006). Anterior cruciate ligament injuries in female athletes Part 2, a meta-analysis of neuromuscular interventions aimed at injury prevention. The American journal of sports medicine, 34(3), 490-498. Komi, P. V. (2008). Stretch-shortening cycle. Strength and power in sport, 2, 184-202. Markovic, G. (2007). Does plyometric training improve vertical jump height? A meta-analytical review. British journal of sports medicine, 41(6), 349-355. Markovic, G., & Mikulic, P. (2010). Neuro-musculoskeletal and performance adaptations to lowerextremity plyometric training. Sports medicine, 40(10), 859-895. Myer, G. D., Paterno, M. V., Ford, K. R., & Hewett, T. E. (2008). Neuromuscular training techniques to target deficits before return to sport after anterior cruciate ligament reconstruction. The Journal of Strength & Conditioning Research, 22(3), 987-1014. Newton, R. U., & Kraemer, W. J. (1994). Developing explosive muscular power: Implications for a mixed methods training strategy. Strength & Conditioning Journal, 16(5), 20-31. 58 29

APPENDIX Sadoghi, P., von Keudell, A., & Vavken, P. (2012). Effectiveness of anterior cruciate ligament injury prevention training programs. The Journal of Bone & Joint Surgery, 94(9), 769-776. Schmidtbleicher, D. (1992). Training for power events. Strength and power in sport, 1, 381-395. Turner, A. N., & Jeffreys, I. (2010). The stretch-shortening cycle: Proposed mechanisms and methods for enhancement. Strength & Conditioning Journal,32(4), 87-99. Verkhoshansky, Y. V., & Siff, M. C. (2009). Supertraining. Verkhoshansky. de Villarreal, E. S. S., González-Badillo, J. J., & Izquierdo, M. (2008). Low and moderate plyometric training frequency produces greater jumping and sprinting gains compared with high frequency. The Journal of Strength & Conditioning Research, 22(3), 715-725. de Villarreal, E. S. S., Kellis, E., Kraemer, W. J., & Izquierdo, M. (2009). Determining variables of plyometric training for improving vertical jump height performance: a meta-analysis. The Journal of Strength & Conditioning Research, 23(2), 495-506. de Villarreal, E., Requena, B., & Newton, R. U. (2010). Does plyometric training improve strength performance? A meta-analysis. Journal of Science and Medicine in Sport, 13(5), 513-522. Wilson, J. M., & Flanagan, E. P. (2008). The role of elastic energy in activities with high force and power requirements: a brief review. The Journal of Strength & Conditioning Research, 22(5), 1705-1715. 59 30