scholarly journals Relationship Between Explosive Strength Capacity of the Knee Muscles and Deceleration Performance in Female Professional Soccer Players

2021 ◽  
Vol 12 ◽  
Author(s):  
Qingshan Zhang ◽  
Aurélie Léam ◽  
Alexandre Fouré ◽  
Del P. Wong ◽  
Christophe A. Hautier
Keyword(s):  
Force Production ◽  
Knee Extensor ◽  
Correlation Coefficients ◽  
Eccentric Contraction ◽  
Peak Torque ◽  
Soccer Players ◽  
Explosive Strength ◽  
Professional Soccer ◽  
Isokinetic Contractions ◽  
Strength Capacity

The present study aimed to investigate the relationship between linear deceleration performance and explosive strength capacity of the knee muscles. Fourteen female professional soccer players completed the maximal sprint deceleration tests and knee flexor (KF) and knee extensor (KE) isokinetic concentric (240° and 60°.s−1) and eccentric contractions (30°.s−1). Linear deceleration performance was evaluated from horizontal breaking force (FH), power (PH), and impulse (IH) during a maximal linear deceleration. The peak torque (PT) of KF and KE, PT ratio between KF and KE (conventional and functional H/Q ratio), rate of torque development (RTD) for each muscle group, and RTD between KF and KE (RTD H/Q) were extracted from the isokinetic contractions. Pearson’s correlation coefficients revealed that the eccentric (30°.s−1) and concentric (60°.s−1, 240°.s−1) KE peak torque, and the concentric KF peak torque (240°.s−1) were significantly correlated with FH, PH, and IH (−0.75<r<−0.54). Moreover, a significant correlation was found between KE RTD during eccentric contraction and FH, PH, and IH (−0.63<r<−0.54). Besides, a significant correlation was observed between RTD H/Q at 60°.s−1 and PH, IH (−0.61<r<−0.57). No significant relationship was observed between the H/Q ratio, KF RTD and deceleration performance. These main findings indicated the importance of the ability to quickly produce high KE eccentric torque, contributing to braking force production. Meanwhile, RTD H/Q should be assessed for its essential role in knee joint dynamic stability and can be a relevant index to determine deceleration performance.

scholarly journals Isokinetic Strength Responses to Season-long Training and Competition in Turkish Elite Soccer Players

2012 ◽  
Vol 31 (1) ◽  
pp. 159-168 ◽  
Author(s):  
Niyazi Eniseler ◽  
Çağatay Şahan ◽  
Hikmet Vurgun ◽  
Hasan Mavi
Keyword(s):  
Knee Extensor ◽  
Peak Torque ◽  
Soccer Players ◽  
Isokinetic Strength ◽  
Professional Soccer ◽  
Knee Strength ◽  
Flexor Muscles ◽  
Angular Velocities ◽  
Soccer Training ◽  
Knee Flexors

Isokinetic Strength Responses to Season-long Training and Competition in Turkish Elite Soccer PlayersThere are not enough studies that describe the isokinetic strength of professional soccer players at high angular velocities. The purpose of this study was to evaluate the seasonal changes in isokinetic strength of Turkish professional soccer players (n=14) over the course of a 24-week soccer season. The isokinetic strength of players who underwent usual soccer training and weekly competition throughout the soccer season was assessed by means of the Biodex System 3 dynamometer with the knee attachment. The peak torque of knee extensor and flexor muscles were measured at angular velocities of 60°/s, 300°/s and 500°/s. Players were tested at the beginning and end of the competitive season. While the first- and second-test measurements did not show significant changes at 60°/s and 300°/s angular velocities, at the end of the training period, players' knee strength changed significantly at 500°/s angular velocities. In addition, the H/Q ratio improved significantly for the dominant as well as non-dominant leg at 500°/s. Significant bilateral strength improvements for knee flexors were also observed at 500°/s. The findings of this study suggest that usual daily soccer training (technical, tactical, power, strength, endurance, flexibility, etc.) and weekly competition might produce changes in knee strength at high angular velocities.

scholarly journals ISOKINETIC PROFILES AND REFERENCE VALUES OF PROFESSIONAL SOCCER PLAYERS

2021 ◽  
Vol 27 (6) ◽  
pp. 610-615
Author(s):  
Guillermo Charneco Salguero ◽  
Francisco García-Muro San José ◽  
Arturo Pérez Gosalvez ◽  
Jose Miguel Cárdenas Rebollo ◽  
Isabel Brígido Fernández ◽  
...  
Keyword(s):  
Reference Values ◽  
Health Professionals ◽  
High Speed ◽  
Peak Torque ◽  
Soccer Players ◽  
Level Of Evidence ◽  
Warm Up ◽  
Professional Soccer ◽  
Average Work ◽  
Torque Values

ABSTRACT Introduction: Isokinetics is a tool commonly used in professional soccer. There is ongoing debate among researchers as to the isokinetic reference values a player should have. Objectives: To determine the absolute peak torque (PT) and average work of professional soccer players in relation to their positions on the field, and to establish the reference values for these variables. Methods: Purposeful sampling was used to select 289 professional soccer players. The sample included 32 goalkeepers, 100 defenders, 98 midfielders, and 59 strikers. The participants were measured preseason. The players were asked to perform a 10-minute warm-up on an exercise bike, and then to perform 5 repetitions at low speed, 10 at medium speed, and 25 at high speed, with 30 to 40-s of rest between each set of repetitions. The contraction method was concentric-concentric in a dynamometer Isomed 2000. Results: The average age, weight, and height of the players was 21.9 years, 74.3 kilograms, and 1.8 meters, respectively. The goalkeepers presented higher PT at the 3 measured speeds, and the higher average work at 180°/s and 240°/s in relation to defenders and midfielders. The strikers presented higher average work at 240°/s in relation to midfielders, and higher PT in relation to the defenders and midfielders. Absolute values were shown and reference values were established. Conclusions: The goalkeepers and strikers were the players that showed the greatest differences in their favor in relation to the other positions. The peak torque values and average work were described in relation to the player's position on the field. This study resulted in the creation of a tool for health professionals working with professional soccer players, providing reference values for these players in relation to their position on the field that can be used as benchmarks, by health professionals, to optimize soccer players’ performance. Level of evidence II, Prospective comparative study.

Peak torque angle, acceleration time and time to peak torque as additional parameters extracted from isokinetic test in professional soccer players: a cross-sectional study

2020 ◽  
pp. 1-12
Author(s):  
Daniel Germano Maciel ◽  
Glauko André Figueiredo Dantas ◽  
Mikhail Santos Cerqueira ◽  
Jean Artur Mendonça Barboza ◽  
Vinícius Vieira De Alencar Caldas ◽  
...  
Keyword(s):  
Peak Torque ◽  
Cross Sectional Study ◽  
Soccer Players ◽  
Sectional Study ◽  
Cross Sectional ◽  
Acceleration Time ◽  
Time To Peak ◽  
Professional Soccer ◽  
Isokinetic Test ◽  
Torque Angle

EXPLOSIVE STRENGTH CAPACITY IN THE LOWER LIMBS AND SPEED PERFORMANCE IN YOUNG SOCCER PLAYERS

2014 ◽  
Vol 48 (7) ◽  
pp. 656.3-657
Author(s):  
I Sannicandro ◽  
A Piccinno ◽  
G Cofano ◽  
N Lupelli ◽  
RA Rosa
Keyword(s):  
Lower Limbs ◽  
Soccer Players ◽  
Explosive Strength ◽  
Strength Capacity ◽  
Speed Performance

Force-velocity relations and fiber composition in human knee extensor muscles

1976 ◽  
Vol 40 (1) ◽  
pp. 12-16 ◽  
Author(s):  
A. Thorstensson ◽  
G. Grimby ◽  
J. Karlsson
Keyword(s):  
Skeletal Muscle ◽  
Knee Extensor ◽  
Dynamic Strength ◽  
Peak Torque ◽  
Human Knee ◽  
Isokinetic Contractions ◽  
Extensor Muscles ◽  
Angular Velocities ◽  
Force Velocity ◽  
Fast Twitch

Standardized measurements of dynamic strength of the kneee extensor muscles were performed in 25 healthy male subjects (17–37 yr) by means of isokinetic contractions, i.e., knee extensions with constant angular velocities. Overall variation between double determinations of maximal torque throughout the 90 degrees arc of motion (0 degrees = fully extended leg) averaged 10% for the different constant velocities chosen. At any given angle of the knee the torque produced was higher for isometric than for dynamic contractions. Dynamic torque decreased gradually with increased speed of shortening. Peak dynamic torque was reached at knee angles in the range: 55–66 degrees, with a displacement toward smaller knee angles with higher angular velocities. Correlations were demonstrated between peak torque produced at the highest speed of muscle shortening and percent as well as relative area of fast twitch fibers in the contracting muscle. In addition muscles with a high percentage of fast twitch fibers had the highest maximal contraction speeds. These observations on intact human skeletal muscle are consistent with earlier findings in animal skeletal muscle preparations.

scholarly journals Evaluating injury risk in first and second league professional Portuguese soccer: muscular strength and asymmetry

2016 ◽  
Vol 51 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Alberto Carvalho ◽  
Scott Brown ◽  
Eduardo Abade
Keyword(s):  
Muscle Strength ◽  
Injury Risk ◽  
Dynamic Control ◽  
Peak Torque ◽  
Soccer Players ◽  
Bilateral Asymmetry ◽  
Hamstring Strain ◽  
Professional Soccer ◽  
Maximal Peak ◽  
The Right

AbstractStrength imbalances between the hamstrings and quadriceps are an essential predictor for hamstring strain in soccer. The study aimed to investigate and compare the muscle strength imbalances of professional soccer players of different performance levels. One hundred and fifty nine senior male professional soccer players from first (n = 75) and second league (n = 84) Portuguese clubs participated in this study. Muscle strength was evaluated with a REV9000 isokinetic dynamometer. Maximal peak torque data were used to calculate quadriceps and hamstrings strength during concentric and eccentric actions, bilateral asymmetry, conventional strength ratios and dynamic control ratios. Second league athletes produced slightly lower conventional strength ratios in the right and left legs (ES = 0.22, p = 0.17 and ES = 0.36, p = 0.023, respectively) compared to the first league athletes. No significant differences were found in dynamic control ratios or in bilateral asymmetry among first and second league athletes. These findings do not show a clear link between the competitive level and injury risk in soccer players. However, some of the differences found, particularly in conventional strength ratios, highlight the importance of performing off-season and pre-season strength assessments to prescribe and adjust individual strength training programs among professional soccer players.

scholarly journals Intra- and Inter-Limb Strength Asymmetry in Soccer: A Comparison of Professional and Under-18 Players

Sports ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 129
Author(s):  
Chris Bishop ◽  
Giuseppe Coratella ◽  
Marco Beato
Keyword(s):  
Knee Extensor ◽  
Peak Torque ◽  
Soccer Players ◽  
Knee Extensors ◽  
Isokinetic Dynamometer ◽  
Percentage Difference ◽  
Strength Asymmetry ◽  
Limb Asymmetry ◽  
Limb Dominance ◽  
Anterior Posterior

(1) Background: the present study examined the isokinetic peak torque exerted by both knee extensors and flexors, anterior–posterior imbalance and the magnitude and direction of inter-limb asymmetry in professional and academy soccer players. (2) Methods: one hundred soccer players (professional = 50, elite academy = 50) volunteered to take part in this investigation. An isokinetic dynamometer was used to measure the knee extensor (quadriceps) and flexors muscle (hamstrings) torques of the limbs as well as inter-limb asymmetries—using a standard percentage difference equation. (3) Results: professional players exhibited significantly greater (effect size [ES] = large) strength levels in the quadriceps and hamstrings under both testing conditions, significantly higher (small to moderate) intra-limb ratio values for 60°·s−1 but not for the 300°·s−1 test condition, significantly (small to moderate) lower inter-limb asymmetry values for all test conditions, with the exception of the hamstrings at 60°·s−1 and the direction of asymmetry was poor to slight, indicating that limb dominance was rarely the same between groups. (4) Conclusions: this study shows that isokinetic assessments, i.e., peak torque exerted by both knee extensors and flexors and intra-limb ratio, and the subsequent inter-limb asymmetry, i.e., magnitude and direction, can differentiate between professional and academy soccer players.

Effect of Acute Static Stretching Duration on Isokinetic Peak Torque in Pubescent Soccer Players

2006 ◽  
Vol 18 (2) ◽  
pp. 252-261 ◽  
Author(s):  
Athanasios Zakas ◽  
George Doganis ◽  
Christos Galazoulas ◽  
Efstratios Vamvakoudis
Keyword(s):  
Knee Flexion ◽  
Force Production ◽  
Peak Torque ◽  
Soccer Players ◽  
Static Stretching ◽  
Warm Up ◽  
Angular Velocities ◽  
Leg Extensors ◽  
Isokinetic Peak Torque ◽  
Stretching Exercises

Although athletes routinely perform warm-up and stretching exercises, it has been suggested that prolonged stretching immediately before an activity might negatively affect the force production. Sixteen male pubescent soccer players participated in the study to examine whether a routine duration of acute static stretching is responsible for losses in isokinetic peak torque production. All participants performed two static stretching protocols in nonconsecutive training sessions. The first stretching protocol was performed three times for 15 s (volume 45) and the second 20 times for 15 s (volume 300). Range of motion (ROM) was determined during knee flexion with the use of a goniometer. The peak torque of the dominant leg extensors was measured on a Cybex NORM dynamometer at various angular velocities. The statistical analysis showed that peak torque did not change following the static stretching for 45 s in all angular velocities, while it decreased (p < .001) in all angular velocities following the static stretching for 5 min. The findings suggest that strength decreases after static stretching exercises may be the result of the performed stretching duration.

Sign in / Sign up

Export Citation Format

Share Document