Combined plyometric exercises for the reactive strength of a
women's soccer team
Abstract
Keywords:
combined plyometrics, reactive strength, training, Soccer.
Introduction
Sports training is a pedagogical,
complex and specialized process that requires an integrating scientific
direction of each of the components of the teaching-learning process to obtain
sports results (Almeida, 2022). In Soccer as a team sport, movements are
executed according to the different game actions. It is a sport in which
actions occur with intermittent and discontinuous characteristics where
strength plays a fundamental role, which is why it is classified as a team
sport with specialized sports preparation content. (Calero, 2019; Arroyo, Cruz
and Estupińan, 2019; Almeida, 2022)
In recent decades, sports
researchers have been analyzing the different factors that influence motor
learning and sports performance. These investigations have intensified,
emerging new proposals for the development of physical abilities and the
technical-tactical actions of the athlete, as an alternative to traditional and
reductionist methodologies, which conceive the training process, based on
repetitive movement patterns in a closed context. (Martin and Camacho, 2021)
In this regard, in team sports,
the use of plyometrics has generated wide interest for coaches seeking to
increase the performance of physical abilities and the competitive
effectiveness of their players (Raya, 2017). Initially it was considered as a
training method reserved for athletes at the highest level of competition.
However, at present it has been gaining in popularity and effectiveness in the
training of lower categories, seen as a dynamic element in the development of
strength. Internationally, in the specific case of Soccer, physical trainers
and coaches are incorporating plyometric training into their training sessions
with good results (Vargas, 2019, Trecroci, et al., 2022).
According to De Pedro (2016),
plyometrics is a method of developing reactive force that uses the
stretch-shortening cycle of the muscle to increase the force produced by the
musculoskeletal system. It also states that there are two types of plyometrics
in terms of their aggressiveness on the athlete's joints, low-impact and
high-impact, which aim to optimize the athlete's ability to increase strength.
Contrary to what has been described above, soccer coaches in Cuba currently see
plyometrics from a very reductionist vision, considering it simply as exercises
that mainly use the athlete's own weight in different types of jumps.
As a consequence of this, in
Cuba, specifically in women's soccer, there are very few works on plyometrics
at an early age, since many coaches and methodologists still consider this
training method dangerous and detrimental to young or poorly trained athletes,
which generates great controversy and a great scientific methodological
challenge. Various bibliographies demonstrate the importance of using
plyometrics as a satisfactory way to develop reactive strength in athletes. In
this sense, there are the works developed by García and Suárez (2019); Harper,
Forsdyke and Thomas (2017) and even more specifically the importance of their
training in Soccer, is evidenced in the works of Yépez and Ramírez (2019) and
Garavito and García (2019).
In this line of thought, research
has been carried out on how to enhance the reactive force in youth soccer
players, such as those developed by Ramírez et. al., (2018). Based on the
criteria of the aforementioned authors and for the purposes of this research,
although plyometrics is considered as the cycle of muscle shortening and
lengthening in the shortest period of time possible, it is undoubtedly very
important with the different levels of manifestation. Of the same.
Hence, it coincides with Vargas
(2019) who affirms that combined plyometrics is the result of mixing it with
coordination, combining its levels, with transfer of low-impact work and
technical-tactical actions. If the context of women's soccer in the Villa Clara
province is analyzed, it is currently one of the most prominent sports in the
Initiation Sports School (ISS) of the province.
However, from the analyzes
carried out by the Provincial Association and the Technical Commission of this
sport, in addition to the reports derived from the Methodological Preparations,
it was determined that regardless of the competitive result in the School
Games, the women's team of the U category -18 years has presented difficulties
in jumping to head (offensive and defensive), fighting for the ball with the
opponent, sprinting in short stretches, getting clear with a spike and
interception of balls and 1 vs 1 duels (offensive and defensive).
All these characteristics reveal
the difficulties they present with respect to the insufficient level of
reactive force in the lower limbs of the players, despite being a determining
capacity of sports performance (García and Suárez, 2019). Being a team where
almost all of the players come from the lower category, they have been having difficulties
with the strength in the lower body. Hence, the objective of the research was
to design combined plyometric exercises to improve the reactive strength of the
lower members of the Villa Clara U-18 women's soccer team.
Materials and methods
During the research process, we
worked with three populations. A population made up of the four women's soccer
coaches of the ISS of Villa Clara, all in a range of between 10 and 20 years of
experience and graduates of a Degree in Physical Culture. A second population
made up of the 16 technical directors belonging to all the teams participating
in the 2020 School Games. We also worked with an intentional sample of 13
players from the ISS Villa Clara women's soccer under-18 team in the year 2020,
selected from a population of 16 because they were the players from the
Under-15 category and who reached the higher category presenting the
aforementioned deficiencies in relation to the reactive force in the lower
limbs.
A third population made up of 11
specialists to determine the relevance of the proposed exercises. The
specialist criterion was considered taking into account the following
characteristics: having at least 10 years of experience as a women's football
coach, having a scientific category of Specialist, Master's or Doctor in
Physical Culture Sciences, having worked in women's football for training
sports or linked to it in some way for at least 5 years and have been linked to
a research project or publication related to the work of strength or plyometrics.
Different methods and techniques
were used such as: document analysis, interview and specialist criteria.
Methodological workshops and brainstorming were used as research techniques.
The investigation went through three stages, the first allowed the systematization
of the theoretical-methodological foundations of the investigation.
In the second stage, the
objective was to design a proposal for combined plyometric exercises for
reactive strength in the Villa Clara women's soccer under-18 team. The diagnosis
of the current state of the reactive force of the lower members of the ISS Villa
Clara women's soccer team under-18 was made. The interviews were applied to the
4 coaches and different tests and measurements to the players. Subsequently,
the proposal was elaborated in correspondence with the results obtained from
the diagnosis. For this, we worked with the population of the 16 Technical
Directors of the teams from each of the provinces, in two work sessions of the
Methodological Workshop within the framework of the 2020 School Games. To
achieve a more viable job, we worked with this population divided into 2
groups. One corresponded to the western region (provinces from Pinar del Rio to
Villa Clara) and another to the eastern region (provinces from Sancti Spíritus
to Guantánamo).
The third stage evaluated the
proposal of combined plyometric exercises for reactive strength. For this
purpose, the proposal was put to the consideration of the specialists, which
they had to analyze from aspects such as: relevance, formal quality,
objectivity and importance of the same. It was carried out in a group
methodological meeting with the specialists to assess the exercises proposed in
the previous phase.
Results and discussion
As a result of the first stage of
the investigation, the position of the authors was defined in the theoretical
criteria cited by different bibliographic sources with respect to women's
soccer, training planning, physical abilities (emphasizing strength), as well
as the plyometrics as a method for its development and assuming the concept of
combined plyometrics offered by Vargas (2019).
When verifying the feasibility of
combined plyometrics to improve the reactive strength of the lower limbs of
U-18 women's soccer players, the four ISS coaches of Villa Clara in the
interviews conducted, offered affirmative answers and argued them, based on the
characteristics of the players in terms of age and their biological and
psychological development.
When analyzing other answers
offered, they express the advantages of applying the reactive force based on
the game actions for which the players must be well prepared, especially in the
lower limbs. They recognized the disadvantage that these have in terms of the
age difference with respect to other players and that this work could help to
equate their performance patterns.
In the second stage of the
investigation, the results of the diagnosis of the reactive force of the lower
limbs of the players that were selected were obtained, which is shown in table
1. Here it is important to point out that since there are no other
investigations on These players, when evaluating the results with the criteria
of the Provincial Association, the averages that were obtained do not satisfy
the demands requested for the sub-18 category.
Table 1. Initial state that the
athletes have regarding the reactive force of the lower limbs.
|
#
P |
S.V (m) |
T.D.S.V (m) |
S.L. s/i (m) |
circumf. thigh (Centimeters) |
circumf. twins (Centimeters) |
||
|
Izq |
Der |
Izq |
Der |
||||
|
1 |
2.08 |
0.23 |
1.67 |
32 |
33.5 |
28.4 |
28.7 |
|
2 |
1.86 |
0.23 |
1.38 |
33.6 |
34 |
35.5 |
35.5 |
|
3 |
2.05 |
0.23 |
1.48 |
34 |
32 |
28 |
27.5 |
|
4 |
2.07 |
0.24 |
1.59 |
30 |
30.5 |
30.5 |
31 |
|
5 |
2.16 |
0.17 |
1.53 |
38.5 |
39 |
38.5 |
39 |
|
6 |
2.28 |
0.24 |
1.45 |
35 |
35.5 |
30 |
30 |
|
7 |
1.94 |
0.22 |
1.5 |
34 |
34.6 |
27.2 |
27.4 |
|
8 |
1.86 |
0.24 |
1.4 |
32.5 |
33.5 |
32.5 |
33.5 |
|
9 |
1.92 |
0.21 |
1.54 |
30.5 |
31 |
22.5 |
22 |
|
10 |
2.08 |
0.25 |
1.7 |
35.5 |
35.5 |
29 |
29.6 |
|
11 |
1.93 |
0.18 |
1.45 |
36 |
36.5 |
36 |
36.5 |
|
12 |
2.04 |
0.22 |
1.39 |
33 |
34 |
26.5 |
25 |
|
13 |
1.91 |
0.24 |
1.55 |
31 |
31 |
31.5 |
31.7 |
|
Average |
2.08 |
0.22 |
1.51 |
33.6 |
33.9 |
30.5 |
30.6 |
Legend: (T.D.S.V) Total takeoff
in the Vertical Jump. (S.V) Vertical Jump. (S.L. s/i) Long jump without
impulse.
During the work sessions of the
Methodological Workshop, the exercise proposal was designed. The starting point
for the determination of the combined plyometric exercises for the reactive
force in the lower limbs of the selected players is based on the conceptions
raised by Anselmi I and II cited in Labandeira (2014) that raises the work of
plyometrics in 4 levels. Levels 0 (zero) and 1 (one) were taken from them for
the conformation of these exercises, taking into account the characteristics of
the players described in the diagnosis made. The frequency of work must be 3
days a week with a space of 48 hours between one work day and another to
guarantee recovery.
Combined plyometric exercises to
improve the reactive strength of the lower limbs according to the level of
plyometrics.
Plyometric exercises Level 0:
They are composed of small jumps made with one foot and both feet with
displacement in a distance of 10 to 12 meters, varying the direction and
modality for each series. The series are of maximum volume and end with the
feeling of fatigue in the calf. The athletes will train barefoot to contribute
in this way to obtaining better results in strengthening the muscles of the
plantar arch. These jumps will be made from the front and return from behind a
distance between 10 and 12 meters for the development of the front and rear
muscles of the lower limbs. These exercises will be executed at the end of the
workouts. For the work of jumps, the organization will be used basically in
which 10 cones or signs will be placed at a distance of 50 cm between them and
a cone at each end, preferably of a different color at a distance of 1 meter.
Activities to be carried out: front jump with one foot, front jump with two
feet and side jump with two feet. Organization of zigzag jumps: zigzag jumps
with one foot and zigzag jumps with two feet.
Organization and content for
plyometric work level 0 + coordination.
Ř Lateral tapping: It will be done
to the left and right on the same cones or signals to later enter the jumps.
Ř Diagonal tapping: It will be done
to the left and right, always ending in the center of the signals and then
entering the jumps.
Ř Frontal Rattling: It will be done
towards the front and back to repeat the exercise and then enter the jumps.
Ř Ladder: It will be carried out
towards the front with different exercises to later enter the jumps.
Ř Rope (Switzerland): Small height
jumps will be performed on the rope at a height less than or equal to the
internal malleolus bone. It can be done with swiss or with the terrain lines to
later enter the jumps.
Ř Quadrilateral: It will be located
on the ground and can be drawn with cones or signs 50 cm wide at grass level.
The jumps will be carried out uninterruptedly and always returning to the
center of the ring to later enter the jumps.
Ř Organization and content for
plyometric work Level 0 (zero) jumps on slopes: The jumps established for the
level will be performed, but with the use of an inclined slope.
Organization and content for
plyometric work Level 1: For this level, what is indicated in Labandeira (2014)
will be used. Each series will count between 8 and 10 jumps. It is convenient
to change the exercise every three series to avoid generating overload patterns
that can lead to joint pain. Each day of level 1, 3 series of 8 -10 repetitions
of 10-15 different exercises are performed. On days of 250 jumps, 8 exercises
will be performed, on days of 300 jumps 10 exercises, and on days of 350 jumps,
12 exercises. The weekly jump volume will increase every week since they are multi-hop,
which is why the jump volumes are so high.
Table 2. Variation of the volumes
of jumps for Level 1
|
Weeks/Day |
Monday |
Wednesday |
Friday |
Total |
|
Weeks 1 Weeks 2 Weeks 3 Weeks 4 |
300 300 350 350 |
250 300 300 350 |
300 300 300 300 |
850 900 950 1000 |
|
Total |
1300 |
1200 |
1200 |
3700 |
Source: Labandeira (2014)
The first day (Monday) is
characterized by working on jumps of moderate intensity made with three
implements: the rope, the ladder and the ring. Different exercises will be
structured according to the recommended amount, performing them with breaks of
between 30" and 120" in order to achieve purity of performance,
coordination and the minimum possible contact time. On the second (Wednesday)
day, a key tool for plyometric work will be used, which are the jumping boxes,
with the following standard measurements: 10cm high x 30cm wide and 90cm long.
The key exercise of this second day is the prisoner.
For day 3 (Friday) all kinds of
multi-jumps are done, with twists, backwards, sideways, the combinations are
endless, always with the use of jumping boxes. For the control of the
components of the load in the planning, the statements made by Labandeira
(2014) are taken as a basis, where it is established that:
Ř Intensity. It refers to the
magnitude of the effort. Plyometric jumps can be divided into different
intensities, ranging from the simplest such as jumping rope or on one foot, to
overweight jumps in the body. The intensity can also be raised in different
ways such as the use of drawers, platforms of different heights or adding
previous races.
Ř Volume. It will be the workload
scheduled for a specific period of time such as weeks, months or sessions. The
workload will have a direct relationship with the intensity, since the higher
the intensity of the plyometric exercises, the lower the programmed volume
should be.
Ř Pause. Plyometric exercises in
soccer, like power exercises, are high-intensity exercises that mainly
stimulate the nervous system, so ample recovery time will be necessary between
work series. In high-intensity tasks, a longer recovery time (3-5 minutes) will
be necessary and in lower intensity tasks, less time (2-3 minutes).
Ř Frequency and Dosage. Frequency
refers to the number of times training is scheduled within a given period, for
example, three plyometric workouts in a work week. Dosage refers to how to
distribute this frequency throughout the week. An interval of 48-72 between
sessions of plyometrics will be optimal and a good warm-up should be done
beforehand, activating the central area of the body and the
joints. (Front, side, diagonal and back tapping between cones and ladder).
Organization and content for
plyometrics work in technical-tactical actions for transfer.
A. Within the technical actions:
Pitch, Receptions and deliveries, Starts in fast driving (7 meters).
B. Within the tactical actions:
Anticipation and delivery, Head clearance, Head shot on goal, Driving 7 meters
hook with center, Shot on goal with the foot.
Description of the content of the
breaks according to the working day.
In the Preparatory or
Conditioning Period it is proposed:
Coordination exercises and level
0 combined with the first day of level 1, both will be worked as established in
terms of execution and methodology.
Table 3. Conception of jumps to
be used in the Preparatory Period from different combinations.
|
Combination 1 |
Combination 2 |
|
Ř Plyometric exercises Level 0 +
Coordination. |
Ř Plyometric exercises Level 0 +
Level 1 day 1. |
|
Ř Plyometric exercises Level 0 +
Level 1 day 1. |
Ř Plyometric exercises Level 1
day 1 on sand and slopes |
|
Ř Level 0 plyometric exercises on
slopes |
Ř Plyometric exercises Level 1 day 2 |
Examples of plyometric exercises
combined with coordination. Combination 1:
Table 4. Level 0 plyometric
exercises + Coordination.
|
Exercise 1: Lateral tapping with front plyometric jumps
Exercise 4: Diagonal tapping with zig-zag plyometric jumps
|
Exercise 3: Ladder with front plyometric jumps
Exercise: Front Plyo Jump Ring with Zig-Zag Plyo Jump
|
|
Exercise 5: Front plyometric jumps on an elevated slope. . |
|
Symbology: 
Cones or signals. 
Quadrilateral plyometric jumps. 
jumps
Displacement. 
ladder.
rope. 
Diagonal
Rattle 
Frontal
rattling. 
Side
rattle.
In the Competitive Period:
The combinations of Plyometrics
level 1 second day + coordination + transfer to speed or other strength are
used through technical-tactical actions, here the volume of jumps and the
frequency of level 1 are undertaken. 3 series of 8 -10 repetitions of 10-15 different
exercises with rest between series of 30 seconds – 120 seconds. If you do not
have the necessary implements, you can perform frontal - posterior and lateral
jumps over an obstacle between 15 and 30 cm high and when you fall in the last
jump you quickly start the indicated technical or tactical action.
Table 5. Conception of jumps to
be used in the Competitive Period from different combinations
|
Combination 3 |
Combination 4 |
|
Ř Level 1 plyometric exercises +
Coordination. |
Ř Plyometrics exercises Level 1 day
3 + transfer to defensive transitions, |
|
Ř Plyometric exercises Level 1
day 2. |
Ř Plyometric exercises Level 1
day 2 + transfer to snatch speed without ball. |
|
Ř Plyometric exercises Level 1
day 3. |
Ř Plyometric exercises Level 1
day 3 with transfer to starting speed w/c offensive transition ball. |
|
Combination 5 |
|
|
Ř Plyometric exercises Level 1
day 3 with defensive actions 1 vs 1 and 2 vs 2 (before dribbling, heading,
interceptions or others. |
|
|
Ř Plyometric exercises Level 1
day 3 with transfer at the end (knocking on the door). |
|
|
Ř Level 1 plyometric exercises on
days 2 and 3 with opponent evasion and shot on goal. |
|
Legend: (S/C) Without and with the ball.
In the following table # 6,
examples of polymetry exercises to be developed in Combination 5 are shown.
Table # 6. Example of plyometric
exercises Level 1 day 3 with transfer to the end (hitting on the door).
|
Figure 1. Exercise 1, Plyometric Jumps in Vault Boxes 3 with Transfer to Finish. |
Figure 2. Exercise 2, Plyometric Vault Box Jumps with Transfer to Finish. (1v1). |
Symbology:
Defense player. 
Attacking player. 
Happens. 
driving
dribble 
Movement
of the player without the ball.
As a result of the third phase,
the criteria of the evaluations made by the specialists were obtained (Table
1). They valued the proposal on the basis of a level of significance
established as Very High (MA), High (A), Average (P) or Low (B) which, based on
their experience, gave each aspect the following valued aspects. In relation to
the Formal Quality criterion, the 11 specialists (100%) give an MA rating to
the proposal. Regarding the Importance and Relevance criteria for the
development of strength, likewise all the specialists valued it as MA. However,
in the Objectivity parameter of its structuring, 9 specialists (81.8%) gave it
an MA rating, and 2 (18.2%) gave it an A rating. Therefore, all the ratings
offered were between MA and A, which which means a positive assessment of them
with respect to the proposal.
The objective of this work was to
design combined plyometric exercises to improve the reactive strength of the
lower limbs of the Villa Clara U-18 women's soccer team. Justifies the need for
them, the results of the diagnosis made to the players where, with respect to
the vertical jump, it can be seen that the results are negative, since only
30.8% of the players (4) are above or in the average. This is a value that is
interpreted as the possibility of achieving success in the dispute of an aerial
ball where it is not possible to exceed 22 cm in height in the jump and must be
taken into account as an important indicator to guide the preparation at work.
of the strength of the lower limbs in terms of achieving a good competitive
result.
The long jump without impulse
also exposes the limitations in the reactive force in the lower members of the
team, 61% of the players (8) are above average and only 7.7% of the players (1)
are in values close to or in the mean. In the circumference of
the thigh, both the left and the right, the values obtained show
the deficiencies in terms of the physical condition of the players. The results
of the measurement of the circumference of the calf show that the highest
percentage does not reach the results of the average, which is why they are
negative for the purposes of determining the physical condition of these
players and therefore the results in the actions of game where they require the
quality of the jump with high levels of reactive force.
In Level 0 plyometric exercises,
they not only aim at osteoarticular adaptation but also at strengthening the
foot musculature and in addition to having proposals aimed at improving
coordination and speed (Mocha and Bonifaz, 2016). As a significant element of
these exercises, the similarity in movement patterns, necessary energy systems
and muscle groups present in the performance of game actions can be mentioned,
hence their great utility (Calero, 2019). From the above it can be deduced that
the purpose of reactive strength training through combined plyometric exercises
in women's soccer is not essentially to build large muscles, as this cannot
always be equated with improvements in reactive strength.
On the contrary, reactive
strength training should be conceived as an ingredient of great importance for
the development of the physical demands of the technical-tactical actions
carried out by the players, in order to solve problems in an environment of uncertainty.
Thus, reactive strength training should not be developed independently of
contemporary trends in the comprehensive preparation of soccer players. The
reactive force represents a fundamental ingredient in the technical and
tactical actions of soccer executed through the use of accelerations and
decelerations, jumping to head, quick changes of direction and shot, duels 1 vs
1 on offense and defense, completion of attacks, actions defenses to avoid the
goal, speed in counterattacks, among others (Raya, 2017; Yépez and Ramírez,
2019).
Therefore, in order to maximize
the potential of the players, the increases in the reactive force have to be
directed towards the specific adaptations of the game (De Pedro, 2016). The
highest stride frequency corresponds to the lowest possible contact phase of
the leg with the ground and, the highest propulsion, when the leg pushes
against the ground to achieve a powerful forward impulse (Chu & Myer, 2016;
Garavito and Garcia, 2019; Vargas, 2019). Therefore, the preparation of the
soccer players is revealed, taking into account the contemporary trends of
Soccer training in their demand to see the training process in a holistic way,
stimulating the use of cognitive development to improve the technical and
tactical performance of the soccer player in function of constant improvements
in their performance on the court while developing the physical qualities that
underpin them.
Finally, it should be noted that
the use of combined plyometric exercises for the development of the reactive
force of the lower limbs of the soccer players in the sub -18 category of the ISS
of Villa Clara is a solution in demand given the existing difficulty. In
addition to having as a novelty that they are structured in 5 different
combinations of levels 0 (zero) and I of plyometrics with coordination and
technical-tactical actions of soccer. These combinations can be planned
according to the preparation period in which the team is. This issue is pending
to be resolved in the independent practice of the high value level received by
the specialists. This research has the limitation that it only remains a
proposal, so the practical implementation of these results will continue.
Conclusions
The women's soccer team of the
EIDE of Villa Clara, category under -18, presents difficulties with respect to
the reactive force of the lower limbs, which present low volume in thighs and
calves, increasing the reaction time before the technical-tactical actions of
soccer. that limits the achievement of favorable results for performance.
The novelty of the combined
plyometric exercises to improve the reactive strength of the lower members of
the team studied is that they are structured into 5 different combinations of
levels with technical-tactical soccer actions, which can be planned according
to the preparation period.
The specialists in their
valuations confer a very high level of significance to criteria of formal
quality, relevance and importance, also granting a high level of significance
to the criteria of objectivity of their structuring, all of which grants their
positive validation.
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