Effects of in-season short-term plyometric training program on leg power,
jump- and sprint performance of elite professional handball players
Dr. Hermassi Souhail
University of Manouba – ISSEP Ksar Said (TUN)
Member of the Union of University Handball Teachers, EHF
ABSTARCT
Our hypothesis was that the addition of an 8-week lower limb plyometric training program
(hurdle and depth jumping) to normal in-season conditioning would enhance measures of
competitive potential (peak power output [PP], jump force, jump height and sprint running
velocity) in professional handball players. The subjects (age 23 ± 0.7 years, body mass 88.5 ±
4.7 kg, height 1.86± 0.06 m, body fat 14.7 ± 2.6%) were randomly assigned to a control
(normal training) group (Gc; n = 12) and an experimental group (Gex; n = 12) that also
performed biweekly plyometric training. A force–velocity ergometer test determined PP.
Characteristics of the squat jump (SJ) and the countermovement jump (CMJ) (jump height,
maximal force and velocity before take-off, and average power) were determined by force
platform. Gex showed gains relative to controls in PP (p <0.01); SJ (height p < 0.01; velocity p
< 0.001), CMJ (height p <0.001; velocity p < 0.001, average power p < 0.01) and all sprint
velocities (p < 0.001 for V5m and Vmax, p <0.01 for VS). We conclude that biweekly
plyometric training of professional handball players improved important components of athletic
performance relative to standard in-season training. Accordingly, such exercises are highly
recommended as part of an annual handball training program.
Key Word: handball, depth jump, running velocity, stretch-shortening cycle, jumping, force–
velocity test
INTRODUCTION
Handball is very complex sports where successful performance depends on a number of basic
abilities in particular endurance, speed, Strength, power, and their derivatives (acceleration,
sprinting, and jumping) all make important contributions to the performance potential of
handball players (18,5). The time-motion analysis showed that during the average 73 minutes
of match time, 825 activity changes were performed at 6 seconds intervals (17). The time
between each activity change (i.e., locomotor category) was 5.6± 1.03 seconds (17). In
addition, the time between each intensity (i.e., from hight to low inetsnity or vice versa) was 55
± 31.6 seconds (17). During the game, players performed 13.8 ± 6.14 jump, 6.7 ±3.95 throws,
30.6 ± 12.38 change of direction, 35 ± 4.9 (28–37) jumps, 134 ± 9.1 (102–144) bocks, and 28 ±
4.3(16–32) ball interceptions (17). A handball match also demands numerous explosive
movements, including 31.4 ±12.44 Stops in the attack and defense, 20.3 ±15.70 one –on-one
situation Sprinting occupies some 6% of playing time and accounts for 10 % of the distance
covered during a match (16). Jumping ability and anaerobic performance are critical to the
handball player, and high scores for the squat counter movement jumps (CMJs) are to be
anticipated in top players (0.40 and 0.65 m, respectively (9). Handball is becoming
progressively more athletic, and short-term muscle power has become crucial in many game
situations.
The power that an individual can develop depends on both force and velocity, as
determined by friction-loaded ergometers (6). Both linear force– and parabolic power– velocity
are increased slightly after 8 weeks of heavy resistance training (6). Strength training is thus
popular as a means of augmenting muscular power and performance in handball players (6, 12).
Plyometric exercise involves stretching the muscle immediately before making a rapid
concentric contraction. The combined action is commonly called a stretch-shortening cycle
(SSC).Nevertheless, the use of SSC seems a particularly appropriate regimen for handball,
where players must frequently jump, run, and sprint. Similar gains of maximal strength have
been reported with traditional strength and plyometric training, but the latter approach appears
to induce greater gains in muscle power (19). Currently available findings regarding jump
height and sprint performance are contradictory. Plyometric training does provide such training
stimuli and has shown evidence to improve explosive actions in young and pubertal (19, 8)
populations. Plyometric exercises constitute a natural part of most sport movements because
they involve jumping, hopping, and skipping (i.e., such as high jumping, throwing, or kicking).
Plyometric training has been advocated as an appropriate approach for sports that require
explosiveness and vertical jumping ability enhancement. Coaches and researchers attempt to
identify the proper handling of program variables in plyometric training, including the
intensity, frequency, and volume of exercise to achieve high levels of jump performance. (8,
10).
Given the contradictory nature of existing information on the efficacy of plyometric
training (4), our aim was to examine the effect of adding a combined hurdle and depth jump
program to the normal in-season regimen of experienced soccer players. We hypothesized that
8 weeks of biweekly plyometric training would enhance leg PP, jump height, and sprint
running velocity relative to players who maintained their normal in-season regimen.
METHODS
Subjects
Twenty-four male players were drawn from handball team (age 23 ± 0.7 years, body mass 88.5
± 4.7 kg, height 1.86± 0.06 m, body fat 14.7 ± 2.6%). Their mean handball experience was 13.2
± 2.2 years. All were examined by the team physician, with a particular focus on conditions
that might preclude plyometric training, and all were found to be in good health. The 24
individuals were randomly assigned between 2 groups: plyometric training (Gex; n = 12; age
22.1 ± 0.7 years, body mass 89.2 ± 4.6 kg, height 1.86± 0.06 m, body fat 14.1±4.2%) and
control (Gc; n = 12; age 23.0 ± 0.5 years, body mass 84.6 ± 4.2 kg, height 1.84 ±0.06 m, body
fat 13.8 ± 1.4%).
Procedures
The study was performed over an 8-week period, from January to March. All subjects had
engaged in the standard training regimen from the beginning of the handball season
(September) until the end of the study (March). During the competitive season (September to
March), subjects trained 7 times a week and played one official game. Tests were completed in
a fixed order over 2 consecutive days.
Testing Schedule
Day 1
Squat and countermovement jumps
Characteristics of the SJ and the CMJ were determined by a force platform (Quattro Jump,
version 1.04; Kistler Instrumente AG, Winterthur, Switzerland) and jump height was
determined as the center of mass displacement, calculated from the recorded force and body
mass. The best of 3 jumps was recorded for each test.
The force–velocity test
Force–velocity measurements for the lower limbs were performed on a standard Monark cycle
ergometer (model 894 E, Monark Exercise AB, Vansbro, Sweden) as described elsewhere (1)
.The parameters measured included Wpeak, maximal pedaling force for lower limbs (F0 LL) and
maximal pedaling velocity for lower limbs (V0LL) (1) . After a 5-minute recovery, the braking
was increased in sequence to 2, 3, 4, 5, 6, 7, 8, and 9% of body mass.
Day 2
Sprint Running Performance
Body displacement was filmed by 2 cameras (Sony Handycam, DCR-PC105E, Tokyo, Japan;
25 frames per second) The first camera filmed the individual over the first 5 m, and a second
camera monitored the sprint between 25 and 30 m. Participants performed 2 trials, separated by
an interval of 5 minutes (3). Appropriate software (Regavi and Regressi; Micrelec,
Coulommiers, France) converted measurements of hip displacement to the corresponding
velocities: the first step after the start (V1S), the first 5 m (V5m), and between the 25 and 30 m
(Vpeak).
Details of plyometric training
Subjects in both experimental and control groups avoided any training other than that
associated with the handball team. Each Tuesday and Thursday for 8 weeks, Gex supplemented
the standard regimen with plyometric training (13), performed immediately before their
standard training sessions (Table 1).
Table1.Training program for plyometric group.
Week
1
2
3
4
5
6
7
8
Exercices x Sets x reps
40-cm hurdle jumps x 5 x 10
40-cm hurdle jumps x 7 x 10
40-cm hurdle jumps x 10 x 10
60-cm hurdle jumps x 5 x 10
40-cm drop jumps x 5 x 10
40-cm drop jumps x 5 x 10
40-cm drop jumps x 5 x 10
40-cm drop jumps x 5 x 10
Statistical Analyses
Means and SDs were calculated using standard statistical methods. Training related effects
were assessed by a 2-way analysis of variance with repeated measure (group3 time). If a
significant F value was observed, Sheffe´’s post hoc procedure was applied to locate pair wise
differences. Percentage changes were calculated as ([posttraining value 2 pretraining value]/
pre training value) 3 100. We accepted p# 0.05 as our criterion of statistical significance,
whether a positive or a negative difference was seen (i.e., a 2-tailed test was adopted).
RESULTS
Plyometric training induced a significant increase in Force–velocity test data also showed
increases of absolute PP (W) and PP relative to body mass (W.kg-1) (Table 2, p < 0.01); Data
for SJ and CMJ were in accordance with these findings (Table 3), with a significant increase in
SJ height relative to Gc (p < 0.01), increases in CMJ height and average jump power (W), but
no significant increase in force after plyometric training. The increase in jump test scores was
accompanied by a significant increase of running velocities (p < 0.001 for both V5m and
Vmax; p < 0.01 for VS) (Table 4).
Table 2. Force–velocity test calculated parameters before and after plyometric training.*†‡
Test
Absolute power (W)
Gex (n= 12)
Gc (n=12)
Pre
881 ±67
610 ± 118
Pos
993 ± 27§
632 ± 139
Power (W.kg-1)
Pre
12.3 ± 0.5
8.4 ± 1.5
Post
14.5 ± 2.0§
9.1 ± 1.6
Maximal pedaling velocity (rpm)
Pre
166.6 ± 11.3
162.1 ±10.1
Post
184.3 ± 6.9
160.0 ±5.7
Maximal force (N)
Pre
74.3 ± 6.1
80.1 ±2.1
Post
93.0 ±4.1#
82.5 ± 4.1
*Gex = plyometric training group; Gc = control group. †Values are given as mean 6 SD. ‡A 2way analysis of variance with repeated measure (group3time) was used to assess the statistical
significance of training related effects.
§p < 0.01.
#p < 0.05.
Table 3. Jumps test values before and after plyometric training.*†‡
SJ
Height (m)
Velocity (m.s-1)
Force (N)
Power (W)
Power (W.kg-1)
Test
Gex (n=12)
Gc (n=12)
Pre
Post
Pre
Post
Pre
Post
Pre
Post
Pre
Post
0.40 ± 0.05
0.44 ± 0.08§
2.2 ± 0.1
2.6 ± 0.4#
1,533 ± 132
1,696 ±143
1,264 ± 125
1,313 ± 137
18.6 ± 1.1
20.1 ± 1.5
0.36 ± 0.01
0.37 ± 0.02
2.2 ± 0.3
2.1 ± 0.1
1,514 ± 127
1,589 ± 160
1,421 ± 130
1,420 ± 121
20.5 ± 1.4
20.7 ± 1.7
CMJ jump
Height (m)
Pre
0.42 ± 0.02
0.39 ± 0.02
Post
0.48 ± 0.01#
0.39 ± 0.02
-1
Velocity (m.s )
Pre
2.3 ± 0.2
2.2 ± 0.2
Post
2.7 ±0.1#
2.1± 0.2
Force (N)
Pre
1,356 ± 121
1,313 ±133
Post
1,381 ± 118¶
1,345 ± 147
. -1
Power (W kg )
Pre
22.9 ± 2.1
21.8 ± 1.5
Post
24.9 ± 1.6§
22.1 ±1.3
*Gex = plyometric training group; Gc = control group; CMJ = countermovement jump; SJ =
squat jump. †Values are given as mean ± SD. ‡A 2-way analysis of variance with repeated
measure (group 3 time) was used to assess the statistical significance of training related effects.
§p < 0.01.
# < 0.001.
¶p < 0.05.
Table 4. Sprint running velocities values before and after plyometric training.*†‡
Test
Vs (m.s-1)
Gex (n=12)
Gc (n=12)
Pre
2.1 ± 0.1
2.1 ± 0.3
Pos
2.5 ± 0.3§
2.2 ± 0.2
. -1
V5 (m s )
Pre
4.1 ± 0.5
3.4 ± 0.1
Pos
4.5 ± 0.6#
3.5 ± 0.2
. -1
Vmax (m s )
Pre
7.2 ± 0.2
7.6 ± 0.2
Pos
9.6 ±0.2#
7.1 ± 0.1
*Gex = plyometric training group; Gc = control group. †Values are given as mean 6 SD. ‡A 2way analysis of variance with repeated measure (group 3 time) was used to assess the statistical
significance of training related effects.
§p < 0.01.
#p < 0.001.
DISCUSSION
The main finding from this study is that, in accordance with our hypothesis, the supplementary
plyometric training program increased several measures of potential handball playing
performance, including the absolute (W) and the relative (Wkg-1) PP of the legs, as assessed by
force–velocity tests (p < 0.001, Table 2), SJ, CMJ, and sprint running, scores (Tables 3 and 4).
Improvements of muscle power and vertical jump height with plyometric training have
been described previously (8, 10, 19). A recent meta-analysis (4) found gains in jump height of
4.7–15% after plyometric training. Our results are consonant with these finding (SJ and CMJ
scores were increased by 11.2 and 14.3%, respectively). The plyometric training program that
we used is similar to that proposed by Markovic et al. (13); they observed increases in both SJ
and CMJ scores relative to controls (p < 0.05). Our results accord with these findings (Table 3).
In contrast, the PP of the CMJ was significantly higher for Gex than for Gc. This may be
because the CMJ involves an SSC and is thus very similar to the plyometric exercises used in
our study.
Moreover, plyometric training is likely to improve coordination (4) and thus to induce a
neuromuscular adaptation that augments power production (2). Behm et al. (2) suggested that
any increase of leg PP induced by plyometric is essentially because of neuronal adaptations:
selective activation of motors units, synchronization, selective activation of muscles, and
increased recruitment of motor units. Many of the CMJ parameters (jump height, velocity,
absolute [W], and relative power [Wkg-1]) tended to increase more than values for SJ (Table 3),
again reflecting similarity between the CMJ and plyometric training. Both CMJ absolute (W)
and relative (Wkg-1) power were significantly improved after plyometric training, but the peak
force showed no statistically significant change; this implies that the improvement in CMJ
power production was largely because of an increase in peak velocity. These results suggest
that in addition to neuromuscular adaptations, our plyometric training induced an increase
average power production. The same conclusion can be drawn from the cycle ergometer data
(Table 2) (PP gains of 6.1 and 8.2% for Wand W.kg-1, respectively). Several previous studies
have suggested that plyometric training can enhance sprinting ability because it uses the SSC.
Mero et al. (14) found a close relationship (p < 0.001) between the rise of the center of gravity
in a drop jump and maximal running velocity.
Our investigation showed improved sprint speeds after plyometric training (Table 4). To
our knowledge, this is the first study to investigate the effect of short-term supplementary
plyometric training on the sprint performance of handball players. However, previous research
has demonstrated that the velocity over distances of 0–30, 10–20, and 20–30 m is increased
significantly (p < 0.05) after 10 weeks of plyometric training (11). A 12-week period of non
depth jump plyometric exercise also improved the 25-m sprint performance of entry-level
collegiate athletes by 9% (15). Similarly, 6 weeks of plyometric training decreased 50-m sprint
times in 9 adult male athletes and a group of basketball players (7). In contrast, Herrero et al.
(7) found no significant gains of SJ height, CMJ height or 20-m sprint time with plyometric
training, and Markovic et al. (13) found no improvements in 20-m sprint times, even though
they used a similar training program to us. These discrepancies may reflect differences in
methodology or the fitness level of the subjects. The meta-analysis of De Villarreal et al. (25)
concluded that subjects with the most sport experience showed the greatest increases in vertical
jump height. This could also be true of sprint performance, explaining some of the discrepant
results.
Differences in the training protocol may also be a factor. In the study of Herero et al. (7),
training consisted of horizontal and drop jumps continued 2 d.wk-1 for only 4 weeks; in our
study, training was more intense (hurdle and depth jumps) and continued for longer (twice a
week for 8 weeks). Maximal intensity sprinting necessitates extremely high levels of neuronal
activation (13). Potential mechanisms for improvements in sprint performance include changes
in temporal sequencing of muscle activation for more efficient movement, preferential
recruitment of the fastest motor units, increased nerve conduction velocity, frequency or degree
of muscle innervations, and increased ability to maintain muscle recruitment and rapid firing
throughout the sprint (7). In the present study, we can assume from earlier studies that the
plyometric training induced neuromuscular adaptations and that these adaptations contributed
to the observed gains in sprint performance.
PRACTICAL APPLICATIONS
The current study indicates that in professional handball players 8 weeks of supplementary
biweekly in-season plyometric training with suitably adapted hurdle and depth jumps
substantially enhances leg PP output, jump height, and sprint velocities over both acceleration
(0–5 m) and maximal speed (0–30 m) phases. We found it quite practical to add this short-term
plyometric training program to traditional in season technical and tactical male handball
training sessions to enhance the performance potential of our players. The gains that were
realized seem greater than could have been anticipated from a corresponding extension of
traditional training (although this point needs further checking). In addition to effects stemming
from the observed increases in muscle volume, there are many potential neuromuscular
explanations of the response to plyometric training, and these merit further investigation. As
the mechanisms become more fully understood, even larger gains of performance may be
realized for a similar increase of training volume.
ACKNOWLEDGEMENT
The authors would like to thank Mr. Karim Helali president of Tunisian Handball Federation
(FTHB) for his Support and encouragement. We also would like to thank the athletes involved
in the study for their contribution.
REFERENCES
1. Arsac, LM, Belli, A, and Lacour, JR. Muscle function during brief maximal exercise:
Accurate measurements on a friction-loaded cycle ergometer. Eur J Appl Physiol Occup
Physiol 74: 100–106, 1996.
2. Behm, DG and Sale, DG. Velocity specificity of resistance training. Sports Med 15: 374–
388, 1993
3. Chelly,MS, Fathloun, M, Cherif, N, Ben Amar, M, Tabka, Z, and Van Praagh, E. Effects of
a back squat training program on leg power, jump- and sprint performances in junior soccer
players. J Strength Cond Res 23: 2241–2249, 2009.
4. De Villarreal, ES, Kellis, E, Kraemer, WJ, and Izquierdo, M. Determining variables of
plyometric training for improving vertical jump height performance: A meta-analysis. J
Strength Cond Res 23: 495–506, 2009.
5. Goran Spori, Dinko Vuleta, Dinko Vuleta Jr. and Milanovi Dragan. Fitness Profiling in
Handball: Physical and Physiological Characteristics of Elite Players. Coll. Antropol. 3: 342010
6. Hermassi S, Chelly MS, Tabka Z, Shephard RJ, Chamari K. Effects of 8-week in-season
upper and lower limb heavy resistance training on the peak power, throwing velocity, and
sprint performance of elite male handball players. J Strength Cond Res. 2011
Sep;25(9):2424-33.
7. Herrero, JA, Izquierdo, M, Maffiuletti, NA, and Garc´ıa-Lo´ pez, J. Electromyostimulation
and plyometric training effects on jumping and sprint time. Int J Sports Med 27: 533–539,
2006.
8. Holcom, W.R., Lander J.E., Rutland R.M., and Wilson G.D. The effectiveness of a modified
plyometric program on power and the vertical jump. J Strength Cond Res 10:89–92. 1996.
9. Ingebrigtsen J, Rodahl S, Jeffreys I. Physical characterstics and abilities of juniors elite
male and female handball players. J Strength Cond Res. 2012 Mar 28.
10. Jeffery F. Vossen., John F. Kramer, Darren G. Burke and Deborahp. Vossen. Comparison
of Dynamic Push-Up Training and Plyometric Push-Up Training on Upper-Body Power and
Strength. J Strength Cond Res. 2000, 14(3), 248–253
11. Kotzamanidis, C. Effect of plyometric training on running performance and vertical
jumping in prepubertal boys. J Strength Cond Res 20: 441–445, 2006.
12. Marques MC, González-Badillo JJ. In-season resistance training and detraining in
professional team handball players. J Strength Cond Res. 2006 Aug;20(3):563-71.
13. Markovic, G, Jukic, I, Milanovic, D, and Metikos, D. Effects of sprint and plyometric
training on muscle function and athletic performance. J Strength Cond Res 21: 543–549,
2007.
14. Mero, A, Luhtanen, P, Viitasalo, JT, and Komi, PV. Relationships between the maximal
running velocity, muscle fiber characteristics, force production and force relaxation of
sprinter. Scand J Sports Sci 3: 16–22, 1981.
15. Moore, EW, Hickey,MS, and Reiser, RF. Comparison of two twelve week off-season
combined training programs on entry level collegiate soccer players’ performance. J
Strength Cond Res 19: 791–798, 2005
16. Pers J, Bon M, Kovacic S, Sibila M, and Dezman B. Observation and analysis of largescale human motion. Hum Mov Sci 21: 295-311, 2002.
17. Póvoas SC, Seabra AF, Ascensão AA, Magalhães J, Soares JM, Rebelo AN Physical and
physiological demands of elite team handball J Strength Cond Res. 2012 Jan 3
18. Sibila, M, Vuleta, D, and Pori, P. Position- related differences in volumes and intensity of
large-scale cyclic movements of male players in handball. Kinesiology 36: 58–68, 2004.
19. Vissing, K, Brink, M, Lønbro, S, Sørensen, H, Overgaard, K, Danborg, K, Mortensen, J,
Elstrøm, O, Rosenhøj, N, Ringgaard, S, Andersen, JL, and Aagaard, P. Muscle adaptations
to plyometric vs. resistance training in untrained young men. J Strength Cond Res 22: 1799–
1810, 2008.
20. Wagner, DR and Kocak, MS. A multivariate approach to assessing anaerobic power
following a plyometric training program. J Strength Cond Res 11: 251–255, 1997