Does plyometric training improve vertical jump height? A meta-analytical review
ABSTRACT
The aim of this study was to determine the precise effect of plyometric training (PT) on vertical jump height in healthy individuals. Meta-analyses of randomised and non-randomised controlled trials that evaluated the effect of PT on four typical vertical jump height tests were carried out: squat jump (SJ); countermovement jump (CMJ); countermovement jump with the arm swing (CMJA); and drop jump (DJ). Studies were identified by computerised and manual searches of the literature. Data on changes in jump height for the plyometric and control groups were extracted and statistically pooled in a meta-analysis, separately for each type of jump. A total of 26 studies yielding 13 data points for SJ, 19 data points for CMJ, 14 data points for CMJA and 7 data points for DJ met the initial inclusion criteria. The pooled estimate of the effect of PT on vertical jump height was 4.7% (95% CI 1.8 to 7.6%), 8.7% (95% CI 7.0 to 10.4%), 7.5% (95% CI 4.2 to 10.8%) and 4.7% (95% CI 0.8 to 8.6%) for the SJ, CMJ, CMJA and DJ, respectively. When expressed in standardised units (ie, effect sizes), the effect of PT on vertical jump height was 0.44 (95% CI 0.15 to 0.72), 0.88 (95% CI 0.64 to 1.11), 0.74 (95% CI 0.47 to 1.02) and 0.62 (95% CI 0.18 to 1.05) for the SJ, CMJ, CMJA and DJ, respectively. PT provides a statistically significant and practically relevant improvement in vertical jump height with the mean effect ranging from 4.7% (SJ and DJ), over 7.5% (CMJA) to 8.7% (CMJ). These results justify the application of PT for the purpose of development of vertical jump performance in healthy individuals.
The effect of two plyometric training techniques on muscular power and agility in youth soccer players.
The aim of this study was to compare the effects of two plyometric training techniques on power and agility in youth soccer players. Twelve males from a semiprofessional football club's academy (age = 17.3 +/- 0.4 years, stature = 177.9 +/- 5.1 cm, mass = 68.7 +/- 5.6 kg) were randomly assigned to 6 weeks of depth jump (DJ) or countermovement jump (CMJ) training twice weekly. Participants in the DJ group performed drop jumps with instructions to minimize ground-contact time while maximizing height. Participants in the CMJ group performed jumps from a standing start position with instructions to gain maximum jump height. Posttraining, both groups experienced improvements in vertical jump height (p < 0.05) and agility time (p < 0.05) and no change in sprint performance (p > 0.05). There were no differences between the treatment groups (p > 0.05). The study concludes that both DJ and CMJ plyometrics are worthwhile training activities for improving power and agility in youth soccer players.
Aquatic Plyometric Training Increases Vertical Jump in Female Volleyball Players.
Applied Sciences
Medicine & Science in Sports & Exercise. 37(10):1814-1819, October 2005.
MARTEL, GREGORY F.; HARMER, MATTHEW L.; LOGAN, JENNIFER M.; PARKER, CHRISTOPHER B.
Abstract:
Purpose: Numerous studies have reported that land-based plyometrics can improve muscular strength, joint stability, and vertical jump (VJ) in athletes; however, due to the intense nature of plyometric training, the potential for acute muscle soreness or even musculoskeletal injury exists. Performance of aquatic plyometric training (APT) could lead to similar benefits, but with reduced risks due to the buoyancy of water. Unfortunately, there is little information regarding the efficacy of APT. Thus, the purpose of this study was to examine the effects of APT on VJ and muscular strength in volleyball players.
Methods: Nineteen female volleyball players (aged 15 +/- 1 yr) were randomly assigned to perform 6 wk of APT or flexibility exercises (CON) twice weekly, both in addition to traditional preseason volleyball training. Testing of leg strength was performed at baseline and after 6 wk, and VJ was measured at baseline and after 2, 4, and 6 wk.
Results: Similar increases in VJ were observed in both groups after 4 wk (APT = 3.1%, CON = 4.9%; both P < 0.05); however, the APT group improved by an additional 8% (P < 0.05) from week 4 to week 6, whereas there was no further improvement in the CON group (-0.9%; P = NS). After 6 wk, both groups displayed significant improvements in concentric peak torque during knee extension and flexion at 60 and 180[degrees][middle dot]s-1 (all P < 0.05).
Conclusions: The combination of APT and volleyball training resulted in larger improvements in VJ than in the CON group. Thus, given the likely reduction in muscle soreness with APT versus land-based plyometrics, APT appears to be a promising training option.
Kinematic Responses to Plyometric Exercises Conducted on Compliant and Noncompliant Surfaces
Crowther, R.G., W.L. Spinks, A.S. Leicht, and C.D. Spinks. Kinematic responses to plyometric exercises conducted on compliant and noncompliant surfaces. J. Strength Cond. Res. 21(2):460–465. 2007.—Jumping is an important performance component of many sporting activities. A number of training modalities have been used to enhance jumping performance including plyometrics. The positive effects of plyometric training on jumping performance are a function of the stretch-shortening cycle phenomenon. However, there has been little research on the effects of the surface on jumping performance. This study examined the effects of performing 2 different plyometric exercises, depth jump (DJ) and counter movement jump (CMJ), on noncompliant (ground) and compliant (mini-trampoline) surfaces. Male participants (N = 20; age = 21.8 ± 3.8 years; height = 184.6 ± 7.6 cm; mass = 83.6 ± 8.2 kg) randomly performed 10 CMJ and 10 DJ on compliant and noncompliant surfaces. Kinematic data were determined via 2-dimensional high-speed video. There were significant (p < 0.05) differences in DJ and CMJ joint and segment range of movement for ankle, knee, hip and trunk, indicating less crouch when the participants performed plyometric exercises on the compliant surface.
Effects of a plyometric program on vertical landing force and jumping performance in college women
Physical Therapy in Sport, Volume 9, Issue 4, Pages 185-192
J. Vescovi, P. Canavan, S. Hasson
Abstract
Objectives
To examine the effects of a plyometric program on peak vertical ground reaction force as well as kinetic jumping characteristics in recreationally athletic college women.
Design
Six week prospective exercise intervention.
Setting
Division I university campus.
Participants
Twenty college females who competed recreationally in basketball were randomly assigned to a training (n=10) or control (n=10) group.
Main outcome measures
The absolute change values for vertical ground reaction force, countermovement jump height, peak and average jump power, and peak jump velocity. Comparisons were made using Mann–Whitney U tests.
Results
Vertical ground reaction force decreased in the intervention group (−222.8±610.9N), but was not statistically different (p=0.122) compared to the change observed in the control group (54.6±257.6N). There was no difference in the absolute change values between groups for countermovement jump height (1.0±2.8cm vs. −0.2±1.5cm, p=0.696) or any of the associated kinetic variables following the 6-week intervention.
Conclusions
Although not statistically significant, the mean absolute reduction in vertical ground reaction force in the training group is clinically meaningful. Eight of the 10 women in the training group reduced vertical ground reaction force by 17–18%; however, improvements in jumping performance were not observed. This indicates that programs aimed at enhancing performance must be designed differently from those aimed at reducing landing forces in recreationally athletic women.
Relationships between three potentiation effects of plyometric training and performance
This study measured the potentiation effects of plyometric training [normalized electromyography (EMG) in triceps surae, stiffness and elastic energy utilization of the Achilles tendon] and investigated the correlations between these effects and performances [voluntary electromechanical delay (EMD) and jump height]. Twenty-one subjects were randomly assigned either to the control group (10 subjects: age 22.3±1.6 years) or to a training group (11 subjects: age 22.1±1.6 years) that performed 8 weeks of plyometric training. Results: As compared with the performances before training, normalized EMG in the soleus were significantly (P≤0.001) increased after 4 and 8 weeks of training. Tendon stiffness, elastic energy storage, release and jump height determined after training were significantly increased (P<0.05), with a concomitantly reduced voluntary EMD (P=0.01). These variables also showed significant differences vs the control group (all P<0.05). The other variables remained unchanged. Correlations were observed between tendon stiffness and either voluntary EMD (r=−0. 77, P=0.014) or jump height (r=0.54, P=0.031). Conclusions: Plyometric training specifically potentiated the normalized EMG, tendon stiffness and elastic energy utilization in the myotendinous complex of the triceps surae. Although these changes are possibly essential determinants, only increases of tendon stiffness were observed to correlate with performance improvements.
THE EFFECTS OF A 6-WEEK PLYOMETRIC TRAINING
PROGRAM ON AGILITY
The purpose of the study was to determine if six weeks of plyometric training can improve an athlete’s
agility. Subjects were divided into two groups, a plyometric training and a control group. The plyometric
training group performed in a six week plyometric training program and the control group did not
perform any plyometric training techniques. All subjects participated in two agility tests: T-test and
Illinois Agility Test, and a force plate test for ground reaction times both pre and post testing. Univariate
ANCOVAs were conducted to analyze the change scores (post – pre) in the independent variables by
group (training or control) with pre scores as covariates. The Univariate ANCOVA revealed a significant
group effect F
2,26
= 25.42, p=0.0000 for the T-test agility measure. For the Illinois Agility test, a
significant group effect F
2,26
= 27.24, p = 0.000 was also found. The plyometric training group had
quicker posttest times compared to the control group for the agility tests. A significant group effect F
2,26
= 7.81, p = 0.002 was found for the Force Plate test. The plyometric training group reduced time on the
ground on the posttest compared to the control group. The results of this study show that plyometric
training can be an effective training technique to improve an athlete’s agility
THE EFFECT OF SHORT-TERM SQUAT VS DEPTH JUMP TRAINING ON VERTICAL JUMP
KL Bebernes, LE Brown FACSM, JW Coburn, B Beam, SM Zinder
Human Performance Laboratory. California State University, Fullerton. Fullerton, CA
A wide variety of sports rely on training techniques to enhance an athlete’s power output. Vertical jump is a reliable way to test for power; therefore the purpose of this study was to determine the effectiveness of a short-term squat (S) training program or a depth jump (DJ) training program on vertical jump performance and one repetition maximum (1RM) strength. 30 male (n=16) and female (n=14) university students (age 24.03 ± 4.67 years, height 67.14 ± 3.38 cm, weight 169.40 ± 33.63 lb) were assigned to three groups: S, DJ or control (C). The subjects in the intervention groups participated in periodized training three days a week for a total of six weeks whereas the control group did not train. Vertical jump height, 1RM and ground reaction force (GRF) were tested before and after training and the alpha level was set at 0.05. Three way ANOVA analysis of variance results demonstrated a significant (p = 0.007) increase in 1RM for the squat group of 15.05% (pre=254 ± 73.09; post=299 ± 81.73lb). Vertical jump increased in all three groups (DJ pre=19.85 ± 4.33 to 20.75 ± 4.30; S pre=20.55 ± 4.44 to 22.2 ± 4.11; C pre=19.43 ± 4.6 to 20.5 ± 4.56) but not significantly different from one another. GRF did not change from pre to post in any group. The primary results of this experiment indicate that vertical jump was not significantly improved with short-term plyometric or squat training using the design and volume in this study. However, a six-week periodized squat training program did increase 1RM strength. Strength coaches may have to design programs with greater volume or longer duration to elicit significant improvements in vertical jump.
Quantifying Plyometric Intensity via Rate of Force Development, Knee Joint, and Ground Reaction Forces
Randall L. Jensen1, 3 and William P. Ebben2
1. Northern Michigan University, Marquette, Michigan 49855, 2. Department of Physical Therapy, Program in Exercise Science, Marquette University, Milwaukee, Wisconsin 53201, 3. Address correspondence to Dr. Randall L. Jensen, E-mail:
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Jensen, R.L., and W.P. Ebben. Quantifying plyometric intensity via rate of force development, knee joint, and ground reaction forces. J. Strength Cond. Res. 21(3):763–767. 2007.—Because the intensity of plyometric exercises usually is based simply upon anecdotal recommendations rather than empirical evidence, this study sought to quantify a variety of these exercises based on forces placed upon the knee. Six National Collegiate Athletic Association Division I athletes who routinely trained with plyometric exercises performed depth jumps from 46 and 61 cm, a pike jump, tuck jump, single-leg jump, countermovement jump, squat jump, and a squat jump holding dumbbells equal to 30% of 1 repetition maximum (RM). Ground reaction forces obtained via an AMTI force plate and video analysis of markers placed on the left hip, knee, lateral malleolus, and fifth metatarsal were used to estimate rate of eccentric force development (E-RFD), peak ground reaction forces (GRF), ground reaction forces relative to body weight (GRF/BW), knee joint reaction forces (K-JRF), and knee joint reaction forces relative to body weight (K-JRF/BW) for each plyometric exercise. One-way repeated measures analysis of variance indicated that E-RFD, K-JRF, and K-JRF/BW were different across the conditions (p < 0.05), but peak GRF and GRF/BW were not (p > 0.05). Results indicate that there are quantitative differences between plyometric exercises in the rate of force development during landing and the forces placed on the knee, though peak GRF forces associated with landing may not differ.
Comparative Effect of Three Modes of Plyometric Training on
Leg Muscle Strength of University Male Students
Ademola Olasupo Abass
Department of Human Kinetics and Health Education
Faculty Of Education, University of Ibadan, Nigeria
E-mail:
dokidemo@yahoo.com Abstract
This study determined the comparative effect of three modes of Plyometrics
training [depth jumping, rebound jumping and horizontal jumping] on leg muscle strength
of untrained University male students. Participants were forty untrained male University
students within the age range of 18-27 years. The randomized pretest-posttest control group
design was adopted. Subjects were randomly assigned to control group, and three
experimental groups based on the types of plyometrics training adopted for the study. The
training programme consisted of twelve weeks of interval training administered three times
a week. Data collected were analyzed using the mean score, standard deviation and range.
Analysis of Covariance [ANCOVA] was used to test for significant differences in the post-
test measures among the treatment and control groups using the pretest score variation as
covariates. Scheffe post hoc analysis was used to determine which of the means were
significantly different. All hypotheses for the study were tested at 0.05 critical level.
Findings revealed that only the depth jumping and rebound jumping training
significantly altered leg muscle strength of subjects (P<0.05). Based on the findings, it was
concluded that plyometrics exercises with depth jumping and rebound jumping
characteristics are best used in developing muscle strength of the lower extremities.
Correlational Effects Of Plyometric Training On Leg Muscle Strength, Endurance
And Power Characteristics Of Nigerian University Undergraduates
Ademola O. Abass
Department of Human Kinetics And Health Education
Faculty of Education
University of Ibadan, Ibadan
Nigeria.
E-mail:
dokidemo@yahoo.comPhone: +2348055436276
Abstract
This study focused on the relationship among strength, endurance and power performance
characteristics of untrained university undergraduates following three different modes of plyometric
training. Participants were 40 untrained volunteer male undergraduates, randomly assigned to
three experimental plyometric training groups of depth jumping, rebound jumping and horizontal
jumping over a distance, and a fourth group which served as the control. The three experimental
groups were made to go through a 12-week exercise programme based on plyometric training
procedures. Interval training method was adopted while the progressive resistance training principle
was considered to determine the duration and intensity of training. Data collected were analyzed
using the mean, standard deviation and range. Relationship between variables was determined
using the Pearson Product Moment Correlation Coefficient. Results show that there were no
significant relationships among the groups in strength and endurance performance characteristics.
Significant correlations were recorded in power performance between horizontal jumping and
rebound jumping group [0.672; P= 0.033]. All other interactions among the groups on leg
power were not significant. On relationship among the three variables based on pooled data across
the groups, significant correlation was recorded only between muscle strength and power
[0.327;P= 0.039]. Correlation between all other variables was found not to be significant. Based
on the finding of the study it was concluded that plyometrics training with repeated jumps
horizontally and that which involves rebound jumping on the spot, are capable of improving leg
muscle power in similar ways. Moreover, the study also concluded that, plyometrics training is
capable of improving leg muscle strength and power significantly
The Effect of Drop Jump Starting Height and Contact Time on Power, Work Performed, and Moment of Force
Walsh, M., A. Arampatzis, F. Schade, and G.-P. Brüggemann. The effect of drop jump starting height and contact time on power, work performed, and moment of force. J. Strength Cond. Res. 18(3):561–566. 2004.—The purposes of this study are (a) to examine the effects of contact time manipulation on jump parameters and (b) to examine the interaction between starting height changes and contact time changes on important jump parameters. Fifteen male athletes performed a series of drop jumps from heights of 20, 40, and 60 cm. The instructions given to the subjects were (a) “jump as high as you can” and (b) “jump high a little faster than your previous jump.” Jumps were performed at each height until the athlete could not achieve a shorter ground contact time. The data were divided into 5 groups where group 1 was made up of the longest ground contact times of each athlete and groups 2–4 were composed of progressively shorter contact times, with group 5 having the shortest contact times. The jumps of group 3 produced the highest maximum and mean mechanical power (p <0.05) during the positive phase of the drop jumps regardless of starting jump height. The vertical takeoff velocities for the first 3 groups did not show significant (p < 0.05) differences. These results indicate that the manipulation of jump technique plays larger role than jump height in the manipulation of important jump parameters.
A Multi-Test Assessment of Anaerobic Power in Male Athletes: Implications for Sport Specific Testing.
The assessment of sport specific anaerobic power using various field and laboratory tests is often used to chart training progress and identify talent. PURPOSE: To determine if an extensive battery of anaerobic tests could successfully identify differing components of athletic power, predict short sprint performance, and distinguish between worst, average, and best performances. METHODS: 18 male college athletes (23 ± 7 yrs, Height 179 ± 5 cm, Body mass 85 ± 12 kg) performed 8 subclasses of tests to assess specific components of anaerobic power (1RM tests: Smith machine back squat, supine bench press, and barbell power clean; Jump tests: CMVJ, CMVJ + 20kg, CMVJ +40 kg, CONJ, 30cm depth jump, plyometric push up, and standing long jump; 10M sprint, 35M sprint; 10 second Quebec cycle test; 7.2kg overhead shot throw, 3.5kg seated shot throw). RESULTS: T-tests were used to assess any statistical differences between jump variables (Height (cm), Ppower (W), Ppower/kg (W/kg)) for the different jump conditions (CMVJ, CMVJ +20kg, CMVJ + 40kg, CONJ, 30cm depth jump). Correlation coefficients (r) and coefficients of determination (R squared) values were calculated between all test variables to assess commonality between tests. Correlations ranged from r = -0.85 (CD 72.4%) to r = 0.91 (CD 83%) Power produced during the depth jump condition was statistically greater (p ≤ 0.05) compared to all other jump conditions. Measure's corrected for body mass (Ppower/kg) produced stronger correlations when body mass was the primary resistance, and when maximal speed (10 m, 35 m sprints (s)), and height (CMVJ, CONJ) were the performance objectives. Regression analysis highlighted statistically significant groupings of variables, which could in part predict performance (10m sprint, 35m sprint (s), height CMVJ, CONJ (cm), Overhead shot distance (m), Plyopush up power (W)) outcomes. The best three groupings accounted for 65% to 85% of the performance outcomes during the performance tests. CONCLUSIONS: A combined multi-test approach of anerobic power is needed to assess varying force/velocity components of short sprint, jumping, and throwing performance with a greater degree of specificity. Care needs to be taken so that tests do not measure the same components of anaerobic power.
Calcium Sensitivity of Human Single Muscle Fibers following Plyometric Training.
BASIC SCIENCES
Medicine & Science in Sports & Exercise. 38(11):1901-1908, November 2006.
MALISOUX, LAURENT 1; FRANCAUX, MARC 1; NIELENS, HENRI 1; RENARD, PATRICIA 2; LEBACQ, JEAN 3; THEISEN, DANIEL 1
Abstract:
Purpose: To study the effect of plyometric training on Ca2+ sensitivity and the influence of troponin T (TnT) isoforms on Ca2+-activation properties in skinned human muscle fibers.
Methods: Biopsies were obtained from the vastus lateralis of eight men before and after the training period. Chemically skinned fibers were evaluated regarding their Ca2+-activation properties and were classified according to their myosin heavy chain (MHC) contents and analyzed regarding their slow and fast TnT isoforms.
Results: After training, significant improvements (P < 0.05) were found for static jump, countermovement jump, 6 x 5-m shuttle-run test, and leg-press performances. An 8% increase in the proportion of type IIa fibers (P < 0.05) was observed. Single-fiber diameters increased by 11% in type I (P < 0.01), 10% in type IIa (P < 0.001), and 15% in type IIa/IIx fibers (P < 0.001). Peak fiber force increased by 35% in type I (P < 0.001), 25% in type IIa (P < 0.001), and 57% in type IIa/IIx fibers (P < 0.01). The Ca2+-activation threshold was not altered by training, but the Ca2+ concentration required to elicit half-maximal activation showed a decreasing trend, with significant changes in type I fibers (P < 0.001). Cooperativity at low Ca2+ concentrations was increased in type I and type IIa/IIx fibers (P < 0.05). Type I fibers exclusively expressed slow TnT isoforms, and type II fibers were always associated with fast TnT isoforms, independent of training status. Therefore, changes in Ca2+ sensitivity after training could not be explained by differential fast or slow TnT isoform expression.
Conclusion: Plyometric training increased single-fiber Ca2+ sensitivity, especially in type I fibers. These changes could not be explained by a modified TnT isoform expression pattern.
The Effect of Short-Term VertiMax vs. Depth Jump Training on Vertical Jump Performance.
Original Research
Journal of Strength & Conditioning Research. 22(2):321-325, March 2008.
McClenton, LaKeysha S; Brown, Lee E; Coburn, Jared W; Kersey, Robert D
Abstract:
The ability to generate lower body explosive power is considered an important factor in many athletic activities. Thirty-one men and women, recreationally trained volunteers, were randomly assigned to 3 different groups (control, n = 10; VertiMax, n = 11; and depth jump, n = 10). A Vertec measuring device was used to test vertical jump height pre- and post-training. All subjects trained twice weekly for 6 weeks, performing approximately 140 jumps. The VertiMax group increased elastic resistance and decreased volume each week, while the depth jump group increased both box height and volume each week. The depth jump group significantly increased their vertical jump height (pre: 20.5 +/- 3.98; post: 22.65 +/- 4.09), while the VertiMax (pre: 22.18 +/- 4.31; post: 23.36 +/- 4.06) and control groups (pre: 15.65 +/- 4.51; post: 15.85 +/- 4.17) did not change. These findings suggest that, within the volume and intensity constraints of this study, depth jump training twice weekly for 6 weeks is more beneficial than VertiMax jump training for increasing vertical jump height. Strength professionals should focus on depth jump exercises in the short term over commercially available devices to improve vertical jump performance.
Use of an Overhead Goal Alters Vertical Jump Performance and Biomechanics
Kevin R. Ford1, 4, Gregory D. Myer1, Rose L. Smith2, Robyn N. Byrnes2, Sara E. Dopirak2, and Timothy E. Hewett1, 3, 2
1. Cincinnati Children's Hospital Research Foundation, Sports Medicine Biodynamics Center, and Human Performance Laboratory, Cincinnati, Ohio 45229, 2. University of Cincinnati, College of Allied Health Sciences, Physical Therapy Department, Cincinnati, Ohio, 3. University of Cincinnati, College of Medicine, Departments of Pediatrics and Orthopaedic Surgery, Cincinnati, Ohio, 4. Address correspondence to Kevin R. Ford, M.S., E-mail:
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Ford, K.R., G.D. Myer, R.L. Smith, R.N. Byrnes, S.E. Dopirak, and T.E. Hewett. Use of an overhead goal alters vertical jump performance and biomechanics. J. Strength Cond. Res. 19(2):394–399. 2005.—This study examined whether an extrinsic motivator, such as an overhead goal, during a plyometric jump may alter movement biomechanics. Our purpose was to examine the effects of an overhead goal on vertical jump height and lower-extremity biomechanics during a drop vertical jump and to compare the effects on female (N = 1Cool versus male (N = 17) athletes. Drop vertical jump was performed both with and without the use of an overhead goal. Greater vertical jump height (p = 0.002) and maximum takeoff external knee flexion (quadriceps) moment (p = 0.04) were attained with the overhead goal condition versus no overhead goal. Men had significantly greater vertical jump height (p < 0.001), maximum takeoff vertical force (p = 0.009), and maximum takeoff hip extensor moment (p = 0.02) compared with women. A significant gender × overhead goal interaction was found for stance time (p = 0.02) and maximum ankle (p = 0.04) and knee flexion angles (p = 0.04), with shorter stance times and lower angles in men during overhead goal time. These results indicate that overhead goals may be incorporated during training and testing protocols to alter lower-extremity biomechanics and can increase performance.
