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Effect of Plyometric Training on Running Performance and Vertical Jumping in Prepubertal Boys

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The purpose of this study was to investigate the effect of plyometric training on running velocity (RV) and squat jump (SJ) in prepubescent boys. Fifteen boys (11.1 +/- 0.5 years) followed a 10-week plyometric program (JUMP group). Another group of 15 boys (10.9 +/- 0.7 years) followed only the physical education program in primary school and was used as the control group (CONT group). Running distances (0-10 m, 10-20 m, 20-30 m, and 0-30 m), were selected as testing variables to evaluate the training program. The total number of jumps was initially 60 per session, which was gradually increased over a period of 10 weeks to 100 per session. Results revealed significant differences between CONT and JUMP groups in RV and SJ. In JUMP group the velocity for the running distances 0-30, 10-20, and 20-30 m increased (p < 0.05), but not for the distance 0-10 m (p > 0.05). Additionally, the SJ performance of the JUMP group increased significantly, as well (p < 0.05). There was no change in either RV or SJ for the CONT group. These results indicate that plyometric exercises can improve SJ and RV in prepubertal boys. More specifically, this program selectively influenced the maximum velocity phase, but not the acceleration phase.
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441
Journal of Strength and Conditioning Research, 2006, 20(2), 441–445
q2006 National Strength & Conditioning Association
E
FFECT OF
P
LYOMETRIC
T
RAINING ON
R
UNNING
P
ERFORMANCE AND
V
ERTICAL
J
UMPING IN
P
REPUBERTAL
B
OYS
C
HRISTOS
K
OTZAMANIDIS
Human Performance and Coaching Laboratory, Department of Physical Education and Sport Sciences, Aristotle
University of Thessaloniki, Thessaloniki, Greece.
A
BSTRACT
.Kotzamanidis, C. Effect of plyometric training on
running performance and vertical jumping in prepubertal boys.
J. Strength Cond. Res. 20(2):441–445. 2006.—The purpose of this
study was to investigate the effect of plyometric training on run-
ning velocity (RV) and squat jump (SJ) in prepubescent boys.
Fifteen boys (11.1 60.5 years) followed a 10-week plyometric
program (JUMP group). Another group of 15 boys (10.9 60.7
years) followed only the physical education program in primary
school and was used as the control group (CONT group). Run-
ning distances (0–10 m, 10–20 m, 20–30 m, and 0–30 m), were
selected as testing variables to evaluate the training program.
The total number of jumps was initially 60 per session, which
was gradually increased over a period of 10 weeks to 100 per
session. Results revealed significant differences between CONT
and JUMP groups in RV and SJ. In JUMP group the velocity
for the running distances 0–30, 10–20, and 20–30 m increased
(p,0.05), but not for the distance 0–10 m (p.0.05). Addition-
ally, the SJ performance of the JUMP group increased signifi-
cantly, as well (p,0.05). There was no change in either RV or
SJ for the CONT group. These results indicate that plyometric
exercises can improve SJ and RV in prepubertal boys. More spe-
cifically, this program selectively influenced the maximum ve-
locity phase, but not the acceleration phase.
K
EY
W
ORDS
. running velocity, squat jump, plyometric program
I
NTRODUCTION
It has been reported that, when myotendinous
tissue is stretched, energy is stored and then
released during muscle shortening (1, 5). This
type of exercise (plyometric or jumping) causes
higher muscle tension compared to convention-
al resistance training (1). For this reason, plyometric
(jumping) exercises are widely recommended for power
enhancement in jumping and running velocity (RV) (32).
Relevant studies with jumping training reported that
plyometric training increased vertical jumping perfor-
mance both for adult (2, 12, 33, 35) and pubertal popu-
lations (10, 21). However, to our knowledge there are no
studies that have examined the influence of plyometric
training on squat jump (SJ) in a preadolescent popula-
tion.
In regard to sprint training, a variety of methods have
been used to improve RV, such as speed training, sprint-
ing against resistances, combined resistance and speed
training, and plyometric training (8, 9, 20, 27). However,
the existing information concerning the effectiveness of
plyometric training on RV in adults is conflicting. Some
studies have found that plyometric training had a signif-
icant effect on RV (10), whereas others have reported no
significant improvements (13). Additionally, positive re-
sults were obtained for RV when resistance training was
combined with plyometric training on consecutive days
(8).
Although a number of speed training studies have
dealt with adults, there is limited information concerning
the effect of these methods on RV performance in the de-
velopmental ages. Mero (22) mentioned that a general
type of training positively affected prepubertal and pu-
bertal boys’ RV. More specific studies reported that
plyometric (10) and sprint (18) training positively affected
the RV of pubertal and prepubertal boys, respectively.
It seems that there is a lack of information concerning
the influence of plyometric training on prepubertal pop-
ulation power performance. It is well known that there
are distinctive differences between prepubertal, pubertal,
and adult performance in strength output, muscle mass,
muscle fiber distribution, neuromuscular activity (30),
and muscle tendon complex compliance (19). Despite the
mentioned differences between adults and preadoles-
cents, certain studies (11, 20) reported that the prepu-
bertal population demonstrated a high adaptability to re-
sistance training, similar to adults. From this point of
view, it would be interesting to examine preadolescents’
adaptability to plyometric training.
Thus, the main purpose of this study was to investi-
gate the influence of plyometric training on running per-
formance and jumping ability in a preadolescent popula-
tion. Taking into consideration that applied training pro-
grams in adult (14) and prepubertal populations (18) had
a selective effect on the different running phases, a sec-
ondary purpose of this study was to examine to what ex-
tent the plyometric training would affect selectively the
RV phases.
M
ETHODS
Experimental Approach to the Problem
This study was designed to prove whether plyometric
training can be applied in a prepubertal population and
to what extent it affects RV and jumping performance.
For this reason, 2 groups of prepubertal boys followed 2
different training programs, 1 consisting of plyometric ex-
ercises and the other comprising the physical education
program. The effectiveness of the applied training pro-
gram was evaluated with pre- and posttesting of RV and
vertical jump. In the pretraining testing period, partici-
pants initially visited the laboratory to be familiarized
with and to practice all testing procedures. They per-
formed all the selected tests during a second visit.
442 K
OTZAMANIDIS
T
ABLE
1. Chronological and anthropometrical characteristics of experimental (JUMP) and control (CONT) groups.
Group Mean age (y)
Sexual
maturation
Mean height
6SD (cm)
Mean body
mass 6SD (kg)
JUMP
CONT
11.1 60.5
10.9 60.7
Phase 1
Phase 1
156.8 66.9
154.2 65.8
49.6 67.3
48.7 69.9
T
ABLE
2. Total sum of jumps per training session.
Week 12345678910
Number 60 60 70 80 70 80 80 90 100 100
Subjects
Thirty healthy, nonathletic boys volunteered to partici-
pate in this study. Boys were divided into an experimen-
tal (JUMP) group (n515) and a control (CONT) group
(n515; Table 1). Children and their parents were in-
formed in detail about the experimental procedure. Par-
ents were asked to complete a written informed consent
for the participation of their children. All children were
examined by a physician and they were found to be at the
first stage of maturation according to Tanner’s criteria
(31). No history of chronic diseases and injuries of the
lower limbs in any of the participants was reported before
training. Taking into consideration the strain caused by
plyometric exercises on muscle-tendon tissue, partici-
pants also were under constant medical monitoring in
case of injury and discomfort. The study was conducted
following the principles of the Ethics Committee of Aris-
totle University of Thessaloniki.
Testing and Procedure
All participants performed a standardized warm-up prior
to testing. They jogged for l0 minutes and then performed
a few submaximal runs and jumps. No stretching exer-
cises were included in the warm-up.
The testing procedure was performed in 2 phases. In
the first phase participants visited the testing area in or-
der to familiarize themselves with the procedure and to
perform the tests. In the second phase of the experiment,
which took place 5 days later, they visited the same place
and retested again.
Sprint Testing. A 30-m distance was selected to eval-
uate running performance. The intermediate phases 0–
10, 10–20, and 20–30 m were assessed, as well. Partici-
pants performed 2 maximal sprint efforts over the dis-
tance of 30 m in an indoor sport hall with a 3-minute
interval between trials. The best (the lowest time) of the
2 sprints was used for further analyses. Boys were en-
couraged to sprint as fast as possible. Sprint times were
recorded to 0.001 second accuracy by an electronic chro-
nometer (Omega system) that was connected to 4 pairs of
opto-reflective switches (TAG HEUER) located at the
start and then at 10-, 20-, and 30-m marks of the 30-m
distance. The system was connected to a printer, which
automatically printed the times for each separate dis-
tance.
Jump Test. SJs were recorded using the Ergojump
Bosco-System (4). In this instrument, 2 switch mats for
the timer were placed side by side and connected by an
adapter to the timer (‘‘start on break contact input’’). The
timer was triggered by the feet of the subject at the mo-
ment of the release from the platform, and stopped at the
moment of touching down. Thus, the flight time of the
subject during the jump was recorded. This method of
flight time calculation assumes that the positions of the
jumper on the platform were the same at takeoff and
landing. The vertical displacement of the body was cal-
culated by the flight time. Participants from a standing
point smoothly flexed their knees at 908, with their feet
on the mat. The subjects were instructed to keep their
hands on their hips throughout the jump. After that they
extended their knees completely and executed SJ. Three
trials were executed and the best one was recorded.
Training Program
The training program lasted 10 weeks and included var-
ious types of jumps. The intensity of the selected exercises
was adjusted according to Chu (7). Exercises specific to
RV (speed-bound) and vertical jumps were included in the
selected exercises, performed with 1 or 2 legs, based on
Diallo et al. (10). The height of the selected vertical
jumps, which were performed with 2 legs, was initially
10–20 cm and gradually increased to 30 cm. The initial
number of jumps per session was 60 and gradually in-
creased up to 100 by the end of the training period (Table
2). The program was performed twice per week. The sets
consisted of 10 jumps each, separated by a 3-minute in-
terval.
A 4-week training program that included running en-
durance, flexibility, coordination, and strength endurance
preceded the specific training program to prevent inju-
ries, as suggested by previous studies (15). All tests were
performed in a closed sport hall area with a stable tem-
perature of 288C.
Statistical Analyses
Means and standard deviations were determined for the
following variables: SJ, running speed of 0–10, 10–20, 20–
30, and 0–30 m. For each dependent variable, a 2-way
analysis of variance (group 3time) with repeated mea-
sures on time was used. When a main or interaction effect
was detected, a paired t-test was performed to determine
specific differences. The level of significance was set at p
#0.05.
Pearson correlation was used in order to detect any
correlations among sprint, anthropometrical, and jump
variables. Pearson correlation also was used to test the
reliability of the selected tests.
R
ESULTS
The test-retest reliability coefficients concerning RV var-
iables ranged from 0.901–0.962 (p,0.05), whereas the
relevant value for SJ was r50.911 (p,0.05). At the
E
FFECT OF
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RAINING IN
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443
T
ABLE
3. Pre- and posttraining mean 6SD time (s) in speed tests.*
Speed
test (m)
Pretraining (s)
CONT JUMP
Posttraining (s)
CONT JUMP
0–10
10–20
20–30
0–30
2.29 60.15
1.75 60.17
1.70 60.22
5.74 60.1
2.24 60.10
1.71 60.11
1.61 60.28
5.55 60.03
2.30 60.14
1.78 60.17
1.74 60.25
5.77 60.3
2.19 60.08†
1.65 60.13†‡
1.56 60.27†‡
5.41 60.6†‡
* CONT 5control group; JUMP 5experimental group.
† Significant difference between groups.
‡ Significant difference within groups.
T
ABLE
4. Pre- and posttraining mean 6SD of vertical jump.*
Group Pretraining Posttraining
JUMP
CONT
22.99 64.495
21.84 65.26
30.96 64.13†
21.22 65.51
* CONT 5control group; JUMP 5experimental group.
† Significant difference between and within groups.
T
ABLE
5. Correlations between different running phases and
squat jump.
Running phase Squat jump*
0–10 m
10–20 m
20–30 m
0–30 m
20.612
20.737
20.737
20.653
*p,0.05.
beginning of the intervention, there were no significant
differences between the 2 groups.
Intergroup Comparisons of Running Performance
The JUMP group (Table 3) showed significantly better
performances after the training program in the interme-
diate distances of 0–10, 10–20, and 20–30 m, and 0–30 m
(p,0.05).
Intragroup Comparisons of Running Performance
Intragroup comparisons (Table 3) revealed an improve-
ment of performance of JUMP group in distances of 10–
20 and 20–30 m (p,0.05), but not for the distance of 0–
10 m. CONT group did not show any improvement in any
of the tested variables (p.0.05).
Intra- and Intergroup Comparisons of SJ
The JUMP group (Table 4) increased significantly the SJ
after the training program (p,0.01) and had better per-
formance than the CONT group (p,0.05).
Correlations
No significant correlations were found between height or
body mass and the performance over sprints of 0–10, 10–
20, and 20–30 m (p.0.05) or the height of squat jump.
However, significant correlations were found between all
tested RV variables and jump tests varying from 0.612–
0.737 (Table 5).
D
ISCUSSION
The main finding of this study is that the applied ply-
ometric training program resulted in an improvement of
the 30-m RV and the vertical jump in preadolescents.
Specifically, this type of training positively affected sprint
performance in the intermediate distances of 10–20 and
20–30 m, but not in the initial distance of 0–10 m. An-
thropometric parameters did not correlate significantly
with any of the running phases, although vertical jump
performance correlated significantly with all running
phases. No injuries or symptoms of discomfort were re-
ported during or after the applied plyometric training
program.
A previous study (9) related to men classified running
performance in 3 phases: initial acceleration up to 10 m,
secondary acceleration from 10–36 m, and thereafter, a
phase of maximal or steady velocity. However, the dura-
tion of acceleration is dependent on numerous factors
such as gender and performance level. In women, the
phase of maximal velocity ranged between 25–35 m (28),
whereas the high-levels sprinters accelerated up to 60 m
(9). To our knowledge, there is no information about the
duration of the acceleration phase in an untrained pre-
pubertal population. The fact that in the present study a
significant difference was observed between the duration
of 0–10 and 10–20 m, but not between the duration of 10–
20 and 20–30 m permitted us to speculate that the dis-
tance between 20–30 m may be roughly considered as the
phase where the children tend to achieve their maximum
velocity. Additionally, the distances between 0–10 and
10–20 m could be considered as initial and secondary (in-
termediate) acceleration.
The influence of the different training methods on
running performance has not been widely studied during
developmental ages and specifically during the prepuber-
tal period. Relevant studies to running programs have
shown that athletic boys have higher RV than do un-
trained population during prepubertal and pubertal stag-
es (22, 23). However, the training programs of these stud-
ies were general and not specific to RV. They included
strength, power, and endurance training without provid-
ing any specific information as to what extent they may
have selectively influenced sprint performance. Kotza-
manidis (17) reported that pure sprint training (short
running distances from 5–30 m, with full recovery inter-
vals) positively influenced 30-m RV. These results (17)
were in line with the findings of Delecluse et al. (9) con-
cerning the application of the same method in untrained
adults, but contrasted the Rimer and Sleivert (27) study
relating to a trained population. To our knowledge, there
are no other studies addressing the influence of plyomet-
ric training on RV in the prepubertal population. For this
reason the results of the present research will be dis-
cussed in relation to adult and pubertal population’s stud-
ies. In adults, relevant studies have pointed out that
jumping exercises that were nonspecific to running per-
444 K
OTZAMANIDIS
formance (i.e., vertical-type jump exercise) did not cause
any effect on running speed (7, 13). On the contrary,
when the applied exercises were completely specific
(speed-bound) to running performance, the training pro-
gram had a positive effect on RV (27). The explanations
of the aforementioned results (27) were based on the as-
sumption that plyometric training reducing conduction
during support phase of the stride increases finally RV.
It is important to comment that in contrast to adult stud-
ies (7, 13, 27), Diallo and colleagues’ (10) and our findings
indicate that for a developmental population, RV also can
be enhanced by using jumping exercises that are nonspe-
cific to RV.
Generally speaking, for RV it has been reported that
the applied training programs demonstrate a selective ef-
fect on the different running phases (8). This selective
effect has been attributed to numerous factors, such as
the differences that were observed between the reported
running phases in dynamic and kinematic parameters
and muscle activation (14, 25). Diallo et al. (10) did not
mention details as to what extent their plyometric pro-
gram affected selectively the running phases. Based on
studies of trained adult populations, it was reported (27)
that the use of speed-bound exercises influenced all run-
ning phases including the initial acceleration (0–10 m).
Our findings are in line with this aforementioned study
(27) only for the intermediary acceleration (10–20 m) and
steady velocity phases (20–30 m). On the contrary, re-
garding the initial acceleration, an increasing tendency
was observed but this improvement was not significant.
This discrepancy between the present results and those
of Rimmer and Sleivert (27) could be explained by the fact
that they have used speed-bound exercises that, in their
opinion, are identical to the kinematic and dynamic pa-
rameters of the stride length and conduction time during
initial acceleration (0–10 m). However, the same authors
(27) mentioned that this adaptation occurred only in the
intermediate distance of 30–40 m. Therefore, the question
of what type of adapted plyometric training may affect
RV needs further examination. In our study we have used
both specific and nonspecific jumping exercises to im-
prove RV, a factor that possibly explains the obtained re-
sults for the 0–10 m. Another factor that probably affect-
ed the obtained results for the 0–10-m distance was the
quality of the applied training program (intensity and vol-
ume) and the power deficit of children compared with
adults (30). It is well known that the performance of the
initial acceleration (0–10 m) is affected mainly by concen-
tric action and power performance (29) whereas the phase
of maximal velocity is affected by muscle-tendon stiffness
as well (6, 24). It seems the applied protocol did not cause
a sufficient power increase to enhance the initial accel-
eration. However, this issue needs further experimental
validation.
Another finding of the present study was that ply-
ometric training increased the vertical jump of the boys.
This issue has not been widely examined during prepu-
berty. Haywood et al. (16) reported that chronic training
caused a jumping enhancement in prepubertal gymnasts
and swimmers. Enhancement of the vertical jump after
plyometric training was reported for the initial (10) and
latest period (21) of puberty. The findings of our study
indicate that plyometric exercises cause an enhancement
in SJ in the prepubertal population regardless of the fact
that their neuromuscular system has not yet completely
matured (30) and their elastic tissue is more compliant
(19) than that of adults. A possible explanation for the
vertical jump enhancement in the current study could be
the rate of force development, power, and stiffness en-
hancement, as already reported in adults (2, 31, 33). How-
ever, this hypothesis needs further investigation for chil-
dren.
Concerning the anthropometrical parameters, previ-
ous studies in adults (20) and pubertal boys (3) have re-
ported that these do not affect running performance, be-
ing in agreement with the current results. The correla-
tions between SJ and all running distances indicate the
important role of lower limb power in all phases of RV,
as it was reported for adult (34, 35) and pubertal (20)
populations. Additionally, they underline that SJ can be
used as a predictor of running performance for preado-
lescents as well.
In conclusion, the plyometric training in prepubertal
boys has a positive effect on RV and vertical jumping per-
formance. However, this training affected predominantly
the phase of maximum velocity indicating specific adap-
tations, which require further research. Additionally, it
was shown that low-intensity plyometrics in combination
with a preceding general preparatory training period
could be applied in the training program of a prepubertal
population without an injury problem. However, further
research is necessary to identify the adaptations, which
could explain the obtained results.
P
RACTICAL
A
PPLICATIONS
The application of plyometric training in children is a con-
flicting issue. It is considered that its application could
be dangerous for children’s muscle-tendon complex. How-
ever, this study showed that low-intensity plyometric ex-
ercises could be used safely during prepuberty. A basic
condition for this type of training is a preceding prepa-
ratory training program including exercise for coordina-
tion, flexibility, and strength endurance. This program
could be considered as a protective mechanism against
possible injuries. Moreover, this type of plyometric exer-
cise could be used as a supplementary training program
for running speed and power enhancement during the
late prepubertal stage.
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... Plyometric ability involves multi-joint movements (i.e., leaping, hopping, skipping) that make use of the stretch-shortening cycle (SSC), in which muscles are stretched quickly (eccentric phase) before being immediately shortened (concentric phase) [2,3]. Despite previous concerns regarding the risk of injury that strength training could pose to children, researchers agree that youth plyometric training (PT) approaches can provide a safe and effective strategy for conditioning and should therefore be included in youth fitness, health promotion, and injury prevention programs [4][5][6][7]. Likewise, studies have shown health benefits from PT, notably improvements in vertical and horizontal jump performances, running speed, agility, change of direction speed (COD), balance ability, and endurance adaptations in children [1,2,8,9]. ...
... Previous studies have highlighted PT's importance in improving jumping ability [1,[7][8][9]34,35]. In fact, it has been reported that interventions using intensive hopping exercises are generally favorable for the optimization of children's jump ability [10]. ...
... Our findings demonstrated that all PT groups achieved similar improvements in linear running speed and agility performances, which were greater than their non-plyometric training counterparts. Prior reports have noted performance gains in linear speed and agility following PT [1,[7][8][9]34]. Thus, the additional gains in linear speed and agility recorded in our experimental groups compared to the CG could be explained by an improvement in ground contact time (especially during acceleration) and musculotendinous stiffness [41][42][43][44]. ...
Article
Full-text available
Plyometric training (PT) has been found to be effective for children’s fitness. However, no study has examined the effects of sex on physical fitness adaptations from surface-type PT in children. This study compared the effects of short-term surface-type PT (firm vs. sand) on the physical fitness of schoolchildren of both sexes. Sixty girls (age = 10.00 ± 1.15 years) and sixty boys (age = 10.02 ± 1.12 years) participated in a short-term (4 weeks), randomized and parallel PT design with pre-to-post measurements. Children were divided into two experimental groups (firm group: PT performed on a clay surface, 20 boys and 20 girls; sand group: PT performed on a dry surface of 20 cm deep sand, 20 boys and 20 girls) and a control group (CG, 20 boys and 20 girls). Squat jump, standing long jump, 20 m sprint, 5-10-5 shuttle, dynamic balance, and maximal aerobic velocity were measured at baseline and after intervention. Both experimental groups showed greater pre-post changes in all assessed variables than the CG (p < 0.0001). No significant differences in pre-post changes were observed relative to surface type or sex (p > 0.05). These findings suggest that a twice-weekly PT program induced physical fitness improvements, which may have transfer to health status during childhood. Additionally, surface type and sex did not affect the training-induced changes in physical fitness.
... Regarding the 20 m sprint capacity, significant gains were verified in the experimental group with the weighted and regulated application of the training program, which is in line with several previous studies [54][55][56]. We must consider the fact that the studies are similar, but not identical, as the school context, age group, and even typology of the training plan differ. ...
... Particularly concerning the improvements that have occurred in the vertical impulse, several studies reinforce the results found, also pointing to quite significant improvements after the application of a training program [13,40,54,60]. Improvements in muscle power and, consequently, in height of the vertical impulse after application of strength training programs have been described previously [59], and our results are consistent with these findings. ...
Article
This study aimed to identify the effects of applying a multivariate training program for low and moderate loads with a reduced volume on physical fitness and throw ability in basketball in an elementary school context. Thirty-two students participated in the study. A training program composed of countermovement jumps, 20m sprints, throws with a basketball ball, chest passes with a basketball ball, and aerobic running was applied for 6 weeks during the physical education class. The students were assessed before and after the training program. The applied tests were stationary two-point shooting test, dynamic 60-second two-point shooting test, shuttle test, sprint, push-ups, and vertical impulse test. A comparison between the pre- and post-training tests was evaluated using standardized mean differences calculated with combined variance and respective 90% confidence intervals. The limits for the statistics were 0.2 (trivial), 0.6 (small), 1.2 (moderate), 2.0 (large), and >2.0 (very large). The results showed positive changes in all tests performed except for throwing ability, for which no significant differences were found between the two analyzed moments. These results demonstrate that the application of a multivariate training program induces improvements in physical fitness but not in throw ability.
... In previous years, plyometric training has been the subject of several studies that have confirmed its impact, as in the Michailidis et al. [19] study, where results showed that it has an impact on soccer players aged 10-11, also Diallo et al. [20] claim to affect the performance of soccer players aged 12-13, Matavulj et al. [21] in basketball players aged 15-16 and in young recreational players [22,23]. A study by Meylan & Malatesta [24] showed that an eight-week plyometric training program has a positive impact on explosive actions in younger soccer players. ...
... Based on the points each study scored on the PE-Dro scale, the final quality assessment scores were defined. With a grand total of 0-3 points, studies were classified as "poor"; 4-5, "fair"; 6-8, "good"; and 9-10, "excellent" [23]. Of all studies included, only one study showed poor ...
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Background: Plyometric training is used to improve human neuro-muscular function and performance in sports. Agility as a necessary motor ability, which is one of the physical components of success in many sports, is especially important for the optimal performance of soccer players. Due to changes in direction and movement during the game, soccer players shows the ability to quickly change direction, stop quickly and perform through fast, accurate, and precise repetitive movements. The aim of this study was to determine the effects of plyometric training on the agility in male soccer players, based on studies that have dealt with the effects of plyometric training. Methods: The search and analysis of the studies were done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyzes (PRISMA) guidelines. A literature search of 4 databases (Google Scholar, PubMed, Web of Science and Research Gate) was conducted using all available studies by November 2021. The identified studies had to meet the following criteria: original longitudinal studies written in English, active male soccer players as sample of participants, experimental treatment of plyometric training with at least two groups of subjects, studies that covered the impact of plyometric training, and studies containing agility tests. Results: A total of 21 studies were included in the systematic review. Improvements in agility tests were small, moderate, and large and ranged from 2% to 14.63%. The greatest improvement in agility was shown in soccer players after a two-week and six-week plyometric program, where the agility test showed a significant improvement of 14.63%. Programs lasting six and eight weeks proved to be the most effective plyometric training program. Plyometric training related to jumps with a progressive increase in intensity and a series of exercises for activation of the lower extremities, there was an improvement of 0.41 s to 0.90 s. Conclusions: Based on the analysis of the included studies, it can be concluded that according to the duration of the program, the minimum period where there can be an improvement in agility and other motor skills is six weeks, and that the usual weekly load is two to three pieces of training.
... Penelitian terhadap Squat Jump (SJ) menemukan bahwa SJ mampu meningkatkan performa remaja selama program 10 minggu dengan frekuensi 2 latihan tiap Minggu. Volume yang digunakan pada penelitian terhadap SJ berkisar antara 60 -100 lompatan tiap sesi (Kotzamanidis, 2006). Hasil yang mirip juga ditemukan pada latihan terhadap laki-laki dewasa dengan frekuensi 4 latihan setiap Minggu selama 12 Minggu (Kubo et al., 2007). ...
... It is reflected from the results of the present study that systematically designed and scientifically structured plyometric training develops the speed ability of athletes (Biswas & Ghosh, 2019). Some studies demonstrated a decrease in sprint time consequently improved speed ability in pre-pubertal to adolescents soccer players (Sáez de Villarreal et al., 2015;Diallo et al., 2001;Kotzamanidis, 2006;Meylan & Malatesta, 2009), others have not (Ingle et al., 2006;Thomas et al., 2009). On the other hand, in resistance training, although improvements in performance after resistance training are most marked for tasks with movement patterns similar to the resistance training exercises themselves, increases in velocity-specific performance have been shown when the testing and training exercises have been different (Delecluse et al., 1995;Hoff & Almåsbakk, 1995;Wilson et al., 1996). ...
Article
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ABSTRACT The purpose of the present study was to compare the effectiveness of Plyometric Training (PT) and Resistance Training (RT) for improving speed ability of the Athletes. Total thirty six (N = 36) district level athletes were randomly selected. All the subjects were divided into three equal groups: i) Resistance Training Group (RTG) as Experimental Group-I, ii) Plyometric Training Group (PTG) as Experimental Group-II and iii) Control Group (CG). Experimental group-I underwent resistance training whereas experimental group-II underwent plyometric training for eight weeks. But the control group did not involve in any of the above treatments. In the present study speed ability was measured through 60 yard dash. To draw the statistical inference analysis of covariance (ANCOVA) was used followed by Tukey’s LSD test as post hoc test. Both RTG and PTG improved significantly with respect to the CG in speed ability. Significant difference was also observed between RTG and PTG in speed ability. It was also confirmed that the PTG improved better than the RTG in speed ability. From the above findings it can be concluded that PT is more effective training means than RT to improve the speed ability of the athlete. Keywords: Plyometric Training, Resistance Training, Speed Ability, Stretch Shortening Cycle.
... Başlangıçtaki hızlanma, sıçrama ve çeviklik, oyuncu hızlı oyunda yer aldığında çok önemli olan patlayıcı eylemlerdir. İlk hızlanma kısa sürat (0-10 m) (Kotzamanidis, 2006) olarak adlandırılabilir ve çeviklik yön değiştirme, başlama ve hızlı bir şekilde durma yeteneği olarak kabul edilebilmektedir (Little ve Williams, 2005;Sheppard ve Young, 2006) Amerikan Spor Hekimliği Koleji (ACSM, 2001, çocuklar için plyometrik antrenman güvenliğine ilişkin daha önce kaygılarını bildirmiştir. Yaralanma riskini en aza indirmek için yakın denetim, uygun teknik ve ilerici eğitim programları yürütülmelidir. ...
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Bu çalışmanın amacı, futbolculara uygulanan tekrarlı sprint ve pliometrik antrenmanlarının sürat ve vücut kompozisyonları üzerindeki etkilerinin incelenmesidir. U-(14-15) kategorisinde yer alan kulüp oyuncularından oluşan deney I, deney II ve kontrol grubu belirlenmiştir. I. deney grubu; Futbol+pliometrk kuvvet antrenmanı, 2.deney grubu Futbol+tekrarlı sprint antrenmanı ve kontrol grubu sadece Futbol antrenmanı yapmışlardır. Katılımcılar haftada üç gün ve 10 hafta boyunca belirlenen antrenman yöntemlerini futbol antrenmanın içeriğinde uygulamışladır. Durarak uzun atlama, dikey sıçrama, 10 m-30 m sprint ve vücut yağ yüzdesi değerleri tespit edilmiştir. Verilerin analizi Repeated Measures Anova ile değerlendirilmiştir. Uzun atlama ön test-son test skorlarına göre gruplar arası farklar düzeyinde deney-II ve kontrol grubunda anlamlı gelişim tespit edilmiştir. 10-30 m, dikey sıçrama skorlarında deney-I ve deney-II de anlamlı farklılık görülmektedir. 10-30 m, vücut yağ yüzdesi değerlerinde gruplar arası farklar düzeyinde dikey sıçrama skorları deney-II grubu açısından anlamlılık söz konusudur. Sonuç olarak tekrarlı sprint ve pliometrik kuvvet antrenmanlarının 10-30 m sprint ve dikey sıçrama performanslarına pozitif katkı sağlamakla birlikte durarak uzun atlamada ise tekrarlı sprint antrenmanlarının öne çıktığı görülmektedir.
... If different kinds of activity that include skips, hops, runs, jumps and medicine ball exercises are used with gradual progress, then there is no reason to believe that plyometrics are inappropriate or unsafe for youths. An increasing number of studies is now supporting the use of plyometric training, and showing that this method could be safe and effective for youths (Matavulj, Kukolj, Ugarković, Tihanyi, & Jarić, 2001;Faigenbaum et al., 2007;Diallo, Dore, Duche, & Van Praagh, 2001;Kotzamanidis, 2006;Lephart et al., 2005). ...
Article
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Resistance training (also known as strength training) is the practice of using free weights, weight machines and elastic bands, or body weight to build muscles, to develop muscle strength, power and muscular endurance. The participation of youths in an organized resistance training program has not always been encouraged, but the positive results of the numerous studies in scientific literature over the past decade have clearly stated the benefits. In addition, the stands that leading world fitness and health organizations and review articles take all state that resistance training can be very beneficial for children and adolescents if done properly. Training must be done in a safe environment, it must be properly designed and under close supervision of a qualified practitioner.
... This transition from the eccentric to the concentric portion of the movement is known as the stretch-shortening cycle. 2 Plyometric training programs have been shown to improve jumping and running performance, and increase bone mass, and lower-extremity strength. [1][2][3][4] Plyometric trainings can lead to adaptive changes in neuromuscular function as a result of increases in neural drive to the agonist muscles, changes in muscle size and architecture, and mechanical characteristic of the muscle-tendon complex. 2 These positive effects on neuromuscular and structural properties should have potential in sports such as volleyball, which involves extensive movements analogous to plyometric drills. ...
Article
The aim of this study was to investigate the effects of plyometric training on vastus lateralis (VL) and patellar tendon size, quadriceps isokinetic strength, and vertical jump height in adolescent female volleyball players. Thirty players (age mean ± SD : 15.7 ± 1.1 years) participated in a 6-week Sportsmetrics ™ plyometric training program. VL thickness, echo intensity, and patellar tendon cross-sectional area were assessed by real-time ultrasound. Isokinetic quadriceps strength and vertical jump were assessed. The VL thickness, quadriceps strength, and VJ height increased and VL–echo intensity decreased after training. We recommended that 6-week Sportmetrics plyometric training program may be implemented in adolescent female volleyball programs especially before the beginning of the volleyball season.
Article
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Objective: This study was carried out to examine the effects of Plyometric training in certain aspects of motor skills. Methods and Materials: Plyometric Training Group (PTG) consisted of 60 male students from various departments at Sarhad University (SUIT), with an average age of 19-25 years. The Control Group consisted of 60 male students with an average age of 19-25 years. The experiment/intervention included of eight weeks plyometric training program. Apart from their daily routine, the control group received no training. Results: The chosen participants' motor abilities were tested, including speed, endurance, explosive power and agility. The statistical treatment computation ANCOVA was used. Conclusion: Plyometric exercise helped male university students enhance their muscle endurance, explosive strength, speed, and ability. It is also eminent that the said program had significantly improved male university students' speed, muscle endurance and lumbar strength. It was concluded that plyometric exercise is superior in boosting male university students' speed, lumbar strength, stamina, and muscle endurance.
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The purpose of this study was to investigate the effect of sprint training upon the running velocity of pre-pubescent boys. Fifteen boys (11.1±0.5yrs old) followed a specific sprint programme for ten weeks (SPR group) and another group of fifteen boys (10.9±0.7yrs old) followed the normal physical education programme and thus acted as the control group (CONT group). Running distances of 0-30m, 0-10m, 10-20m and 20-30m and squat jumps were selected as testing variables to evaluate the training programme. The sprint training programme consisted of short sprints from 5-30m with a resting interval of 3min between repetitions and 5min between sets. The total running distance was initially 150m and gradually increased to 300m. After the ten week sprint programme, the running velocity and the height of squat jumps in the SPR group increased significantly. This programme had a specific effect on the intermediary phases of the running performance; the velocity was increased for the distances 0-10m and 10-20m, but not for the distance 20-30m. The CONT group did not increase any of the tested parameters. These results indicate that the applied sprint training could increase the velocity of the acceleration phase, but not the phase of maximal velocity. The increased height observed in squat jumps in the SPR group could probably be attributed to the stretch-shortening cycle performance, which occurs during running and would have caused the appropriate adaptations to the muscle tendon unit.
Article
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The purpose of this study was to compare the effects of 3 different training protocols-plyometric training, weight training, and their combination-on selected parameters of vertical jump performance and leg strength. Forty-one men were randomly assigned to 1 of 4 groups: plyometric training (n = 11), weight training (n = 10), plyometric plus weight training (n = 10), and control (n = 10). Vertical jump, mechanical power, flight time, and maximal leg strength were measured before and after 12 weeks of training. Subjects in each training group trained 3 days per week, whereas control subjects did not participate in any training activity. Data were analyzed by a 2-way (4 [middle dot] 2) analysis of variance (repeated-measures design). Results showed that all training treatments elicited significant (p < 0.05) improvement in all tested variables. However, the combination training group produced improvements in vertical jump performance and leg strength that were significantly greater than improvements in the other 2 training groups (plyometric training and weight training). This study provides support for the use of a combination of traditional and Olympic-style weightlifting exercises and plyometric drills to improve vertical jumping ability and explosive performance in general. (C) 2000 National Strength and Conditioning Association
Article
Vertical jump ability is a requirement for success in a number of sports. This paper reviews three broad categories of strength training methods by which vertical jump ability is commonly improved. It examines a theoretical rationale for a strength training program by identifying the neuromechanical factors that affect jumping performance. The results of studies using general, special, and specific strength training exercises are also examined. The role and application of these different exercises for athletes of different abilities is discussed. Practical methods for analyzing jumping performance and their relevance to strength training are also discussed.
Article
Fourteen female NCAA Division I collegiate volleyball players were monitored during a 12-week off-season strength and conditioning program. Physical characteristics (mean +/- standard deviation) included: age, 19.6 +/- 0.6 years; height, 171.9 +/- 6.8 centimeters; weight, 64.3 +/- 7.0 kilograms. Training included resistance exercise, plyometrics, aerobic endurance exercise and on-court volleyball practice. At the beginning of the study, starters (ST, n = 6) were compared with non-starters (NST, n = 8), and were found to be faster, more flexible and stronger. ST were still stronger when one-repetition maximum (1 RM) values were corrected for fat-free mass (FFM). Ten subjects completed the 12-week strength and conditioning program and participated in the post-training tests. ST and NST responded similarly to the training program for all physical and performance tests. Significant improvements were observed for FFM, sport-specific peak and mean isometric force, vertical jump (VJ), shoulder flexibility, 1 RM strength and 1 RM/FFM for the bench press, military press, squat and hang power clean, and isokinetic leg extension torque at 1.05 and 3.14 rads*sec-1. Furthermore, two-mile run times and sit-up performance (in 60 seconds) also improved. Significant decreases were observed for VJ endurance. Over the course of the training program, the relationship between 1 RM strength and FFM decreased, while shoulder flexibility was increasingly related to sport-specific isometric strength. Isokinetic testing did not reflect the magnitude of changes in 1 RM tests. Thus, while differences appear to exist in physical characteristics between starters and non-starters, it was shown that most physical and performance variables for ST and NST can be improved with a comprehensive strength and conditioning program for female collegiate volleyball players. (C) 1991 National Strength and Conditioning Association
Article
To determine the effects of a sprint-specific plyometrics program on sprint performance, an 8-week training study consisting of 15 training sessions was conducted. Twenty-six male subjects completed the training. A plyometrics group (N = 10) performed sprint-specific plyometric exercises, while a sprint group (N = 7) performed sprints. A control group (N = 9) was included. Subjects performed sprints over 10-and 40-m distances before (Pre) and after (Post) training. For the plyometrics group, significant decreases in times occurred over the 0-10-m (Pre 1.96 +/- 0.10 seconds, Post 1.91 +/- 0.08 seconds, p = 0.001) and 0-40-m (Pre = 5.63 +/- 0.18 seconds, Post = 5.53 +/- 0.20 seconds, p = 0.001) distances, but the improvements in the sprint group were not significant over either the 0-10-m (Pre 1.95 +/- 0.06 seconds, Post 1.93 +/- 0.05 seconds) or 0-40-m distance (Pre 5.62 +/- 0.14 seconds, Post 5.55 +/- 0.10 seconds). The magnitude of the improvements in the plyometrics group was, however, not significantly different from the sprint group. The control group showed no changes in sprint times. There were no significant changes in stride length or frequency, but ground contact time decreased at 37 m by 4.4% in the plyometrics group only. It is concluded that a sprint-specific plyometrics program can improve 40-m sprint performance to the same extent as standard sprint training, possibly by shortening ground contact time. (C) 2000 National Strength and Conditioning Association
The relationships between ground reaction forces, electromyographic activity (EMG), elasticity and running velocity were investigated at five speeds from submaximal to supramaximal levels in 11 male and 8 female sprinters. Supramaximal running was performed by a towing system. Reaction forces were measured on a force platform. EMGs were recorded telemetrically with surface electrodes from the vastus lateralis and gastrocnemius muscles, and elasticity of the contact leg was evaluated with spring constant values measured by film analysis. Data showed increases in most of the parameters studied with increasing running speed. At supramaximal velocity (10.36±0.31 m×s−1; 108.4±3.8%) the relative increase in running velocity correlated significantly (P<0.01) with the relative increase in stride rate of all subjects. In male subjects the relative change in stride rate correlated with the relative change of IEMG in the eccentric phase (P<0.05) between maximal and supramaximal runs. Running with the towing system caused a decrease in elasticity during the impact phase but this was significant (P<0.05) only in the female sprinters. The average net resultant force in the eccentric and concentric phases correlated significantly (P<0.05−0.001) with running velocity and stride length in the maximal run. It is concluded that (1) increased neural activation in supramaximal effort positively affects stride rate and that (2) average net resultant force as a specific force indicator is primarily related to stride length and that (3) the values in this indicator may explain the difference in running velocity between men and women.
Article
The relationships between muscle fibre characteristics and the physical performance capacity of trained athletic boys (aged 11-13 years) were studied over 2 days. The subjects were divided into two groups according to muscle fibre distribution. The 'fast' group (FG) comprised 10 subjects (sprinters, weightlifters, tennis players) with more than 50% fast-twitch fibres (type II), and the 'slow' group (SG) comprised 8 subjects (endurance runners, tennis players, one weightlifter) with more than 50% slow-twitch fibres (type I) in their vastus lateralis muscle. The 'fast' group had 59.2 +/- 6.3% and the 'slow' group had 39.4 +/- 9.8% type II fibres. Other clear differences (P less than 0.05-0.01) between the groups were observed as regards reaction time, rate of force development and rise of the body's centre of gravity in the squatting jump. For these variables, the 'fast' group was superior to the 'slow' group. Muscle fibre distribution (% type II) correlated (P less than 0.05-0.01) negatively with reaction time. Muscle fibre area (% type II) correlated negatively with reaction time (P less than 0.05-0.001) and positively with chronological age (P less than 0.05) height (P less than 0.05), mass (P less than 0.001), serum testosterone (P less than 0.05), force production (P less than 0.05-0.01) and blood lactate (P less than 0.05) in the 60-s maximal anaerobic test. There were no significant correlations between muscle fibre characteristics and maximal oxygen uptake. The present study assumes that heredity partly affects the selection of sporting event. Growth, development and training are associated with muscle fibre area, which affects the physical performance capacity of the neuromuscular system in trained young boys.
Article
Possible changes in muscle size and function due to resistance training were examined in prepubertal boys. Thirteen boys (9-11 yr) volunteered for each of the training and control groups. Progressive resistance training was performed three times weekly for 20 wk. Measurements consisted of the following: 1 repetition maximum (RM) bench press and leg press; maximal voluntary isometric and isokinetic elbow flexion and knee extension strength; evoked isometric contractile properties of the right elbow flexors and knee extensors; muscle cross-sectional area (CSA) by computerized tomography at the mid-right upper arm and thigh; and motor unit activation (MUA) by the interpolated twitch procedure. Training significantly increased 1 RM bench press (35%) and leg press (22%), isometric elbow flexion (37%) and knee extension strength (25% and 13% at 90 degrees and 120 degrees, respectively), isokinetic elbow flexion (26%) and knee extension (21%) strength, and evoked twitch torque of the elbow flexors (30%) and knee extensors (30%). There were no significant effects of training on the time-related contractile properties (time to peak torque, half-relaxation time), CSA, or %MUA of the elbow flexors or knee extensors. There was, however, a trend toward increased MUA for the elbow flexors and knee extensors in the trained group. Strength gains were independent of changes in muscle CSA, and the increases in twitch torque suggest possible adaptations in muscle excitation-contraction coupling. Improved motor skill coordination (especially during the early phase of training), a tendency toward increased MUA, and other undetermined neurological adaptations, including better coordination of the involved muscle groups, are likely the major determinants of the strength gains in this study.