Isokinetic Torque Levels for Knee Extensors and Knee Flexors in Soccer Players

1986 ◽  
Vol 07 (01) ◽  
pp. 50-53 ◽  
Author(s):  
B. Öberg ◽  
M. Möller ◽  
J. Gillquist ◽  
J. Ekstrand
Symmetry ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1664
Author(s):  
Nejc Šarabon ◽  
Darjan Smajla ◽  
Nicola A. Maffiuletti ◽  
Chris Bishop

Despite growing research in the field of inter-limb asymmetries (ILAs), little is known about the variation of ILAs in different populations of athletes. The purpose of this study was to compare ILAs among young basketball, soccer and tennis players. ILAs were assessed in three different types of tests (strength, jumping and change of direction (CoD) speed), each including different tasks: (1) bilateral and unilateral counter movement jump, (2) isometric strength of knee extensors (KE) and knee flexors (KF), and (3) 90° and 180° CoD. Generally, the absolute metrics showed strong reliability and revealed significant differences (p < 0.05) among the three groups in KE maximal torque, KE and KF rate of force development and in both CoD tests. For jumping ILAs, power and force impulse metrics exhibited significant between-limb differences between groups, compared to jump height. For strength and CoD speed ILAs, only KF maximal torque and 180° CoD exhibited significant differences between groups. Greater KF strength ILAs in soccer players and counter-movement jump ILAs in tennis players are most probably the result of sport-specific movement patterns and training routines. Sport practitioners should be aware of the differences in ILAs among sports and address training programs accordingly.


2017 ◽  
Vol 10 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Michal Lehnert ◽  
Petr Stastny ◽  
James J. Tufano ◽  
Pavel Stolfa

Background:During soccer-specific movements, the strength of knee extensors and flexors is of great importance and achieving certain strength ratios between the two has been identified as an important parameter for reducing the risk of soft tissue injuries around the knee.Objective:The aim of the study was to evaluate changes in isokinetic strength of the knee flexors and extensors and their strength ratios in elite adolescent soccer players.Methods:Before and after 10 weeks of standard pre-season soccer training with progressive eccentric hamstring exercises, the players (n=18; age 17.1±0.4 years) participated in isokinetic testing to assess concentric and eccentric peak torque at 60°·s-1.Results:After 10 weeks of training, the peak eccentric torque of the non-dominant quadriceps increased (p=0.018; ω=0.24). Additionally, the average eccentric work increased in the dominant hamstrings (p=0.007; ω=0.23), dominant quadriceps (p=0.02; ω=0.31), non-dominant hamstrings (p=0.003; ω=0.25 and non-dominant quadriceps (p=0.01; ω=0.37). Lastly, the isokinetic functional ratio (eccentric hamstrings-to-concentric quadriceps) increased in favor of eccentric hamstring strength in the non-dominant limb (p=0.04; ω=0.31).Conclusion:The results of the study indicate that pre-season training induced suboptimal changes in the isokinetic strength of the knee flexors and extensors in elite adolescent soccer players. However, the lack of injuries combined with an apparent lack of preparedness explained by slow velocity isokinetic testing indicates that future research should investigate other forms of strength testing to determine soccer-specific preparedness such as isokinetic dynamometry at higher speeds (i.e.180°.s-1or 240°.s-1) and traditional weight-room testing such as 1RM tests.


1988 ◽  
Vol 09 (06) ◽  
pp. 448-450 ◽  
Author(s):  
P. Rochcongar ◽  
R. Morvan ◽  
J. Jan ◽  
J. Dassonville ◽  
J. Beillot

2021 ◽  
pp. 1-8
Author(s):  
Mikola Misjuk ◽  
Indrek Rannama

BACKGROUND: Lower limb muscular asymmetry is not well studied and may have a negative impact on performance. OBJECTIVE: To estimate how muscular strength and strength asymmetry affect jumping performance in soccer players. METHODS: Twenty-eight male professional soccer players took part in the study. The countermovement jump (CMJ) without arm swing was used to determine jumping height. Muscle strength was measured concentrically at 60 and 300∘/s. RESULTS: The peak moment of the knee extensors was positively and significantly correlated with the CMJ; r= 0.608 at 300∘/s and r= 0.489 at 60∘/s. The asymmetry of the knee flexors between the stronger and weaker leg was negatively and moderately correlated with the CMJ at 300∘/s (r=-0.396). The regression model (R2= 0.474) showed that an increase of 0.18-Nm/kg in the relative strength of the knee extensors at 300∘/s (by one SD) was related to an increase of 3-cm in the CMJ. Reducing the asymmetry of the knee flexors by 6.8 percentage points (by one SD) was related to a rise of 1.7-cm in the CMJ. CONCLUSIONS: Greater strength in the knee extensors, preferably tested at higher velocity, and reduced asymmetry in the strength of the lower hamstring muscles have a statistically significant effect on the CMJ.


2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
P Oleinik ◽  
AN Sumin ◽  
AV Bezdenezhnykh

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Federal State Budgetary Scientific Institution Research Institute for Complex Issues of Cardiovascular Diseases Introduction The purpose was to evaluate the effectiveness of NMES in patients with complications after cardiac surgery. Methods This study was 37 patients who had significant postoperative complications after cardiovascular surgery. Participants were randomly - NMES group, n = 18; control, n = 19. It was not possible to blind the investigator. Analyzed basic clinical data. The dynamometry of the muscles upper and lower extremities was carried out, as well as a 6-minute walk test (6MWT). Also, the thickness of the quadriceps was measured using ultrasound.The patients underwent NMES on the quadriceps femoris muscle, daily from the third postoperative day, until discharge. The duration session was 90 minutes. Outcomes No differences were found in the baseline characteristics of the groups, including the results of laboratory and instrumental studies. Groups were comparable in the surgery and perioperative parameteres. The initial strength indicators also had no significant differences in the groups. At discharge knee extensors strength (KES) was significantly higher in the NMES group. The knee flexor strength (KFS) and handgrip strength (HF) increased the same in both groups. The quadriceps crosssectional area (CSA) muscle increased more in the NEMS group than in the control to the time of discharge. Average KES increased to a greater extent in the NMES group. At the same time, average and maximum KFS increased equally in both groups. A 6MWT before discharge did not show a difference between groups (P=.166). The NMES course did not affect the duration of hospitalisation (P=.429). Discussion This pilot study show beneficial effects of NMES on muscle strength in patients with complications after cardiovascular surgery. Physical tests initially and in dynamics NEMS Group (n = 18) Control group (n = 19) Baseline Discharge Baseline Discharge P-level Right knee extensors strength (kg) 20,3 [17,9; 26,1] 28,05 [23,8; 36,2] * 20,1 [18,6; 25,4] 22,3 [20,1; 27,1] * 0,004 Left knee extensors strength (kg) 17,75 [15,5; 27,0] 27,45 [22,3; 33,1] * 20,8 [17,5; 24,2] 22,5 [20,1; 25,9] * 0,017 Right knee flexors strength (kg) 14,85 [11,7; 19,5] 17,5 [14,1; 23,4] * 16,9 [13,1; 23,8] 19,2 [12,5; 26,4] * 0,971 Left knee flexors strength (kg) 14,7 [12,6; 19,6] 19,75 [15,9; 24,2] * 16,2, [10,4; 25,1] 18,8 [13,1; 27,7] * 0,889 6-MWT (m) 148,5 [108,5; 174,0] 288,0 [242,0; 319,0] * 169,0 [115,0; 217,0] 315,0 [277,0; 400,0] * 0,166 Right handgrip strength (kg) 24,5 [15,0; 33,0] 25,5 [19,0; 36,0] * 27,0 [18,0; 32,0] 30,0 [20,0; 35,0] * 0,795 Left handgrip strength (kg) 17,0 [12,0; 27,0] 21,0 [15,0; 31,0] * 19,0 [14,0; 29,0] 23,0 [16,0; 30,0] * 0,541 * - p-level from baseline data &lt; 0,05 ** - p-level from baseline data ≥ 0,05


2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
P Oleinik ◽  
AN Sumin ◽  
AV Bezdenezhnykh

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Research Institute for Complex Issues of Cardiovascular Diseases Aim To evaluate the effects of neuromuscular electrostimulation in the prehabilitation and prevention of muscle weakness in patients awaiting cardiac surgery. Materials and methods 122 patients waiting for elective cardiac surgery were included. Exclusion criteria: age less than 25 and more than 80 years; emergency and urgent surgical interventions; arthropathies; low pain threshold; rhabdomyolysis and other myopathies; cognitive dysfunction. Routine laboratory and instrumental examinations were performed in all patients upon admission to the hospital, as part of a standard examination. 62 patients were randomly selected for the preoperative NMES group, in addition to the standard preoperative preparation and treatment program. The standard program included 60 control patients. Patients of the NMES group underwent quadriceps stimulation for at least 5 sessions, lasting 90 minutes, daily before surgery. Results. The groups were comparable and did not have significant differences in gender and age characteristics, according to the main clinical and anamnestic data and types of operations. Initially, there were no differences in the state of the muscles of the lower extremities, the distance of the six-minute walking test (6MWT), and the strength of the hand grip. After NMES, there was an increase in muscle strength relative to the control group, both stimulated muscle groups and unstimulated antagonist muscles, as well as a greater 6MWT distance and hand compression force. All the differences were significant. Conclusions The course of pre-rehabilitation of NMES before surgery, allowed to maintain, and in some cases improve the condition of the muscle frame of the lower extremities. A positive effect was observed not only in stimulated muscle groups, but also in antagonist muscles Indicators of muscle status NMES (n = 62) Control group (n = 60) Baseline Discharge Baseline Discharge P-level Right knee extensors strength (kg) 24,4 [18,3; 31,4] 30,4 [23,8; 36,2]* 24,7 [20,1; 33,2] 22,25 [18,9; 30,4] &lt;0,001 Left knee extensors strength (kg) 23,8 [19,3; 31,3] 29,2 [23,6; 35,4]* 25,75 [19,2; 31,3] 22,9 [18,9; 27,8] &lt;0,001 Right knee flexors strength (kg) 18,9 [13,3; 24,0] 21,7 [16,6; 25,1] 19,55 [13,1; 26,0] 16,7 [12,1; 23,3] 0,006 Left knee flexors strength (kg) 19,3 [14,3; 24,5] 21,9 [17,3; 26,7] 19,5 [13,0; 24,3] 18,2 [13,4; 22,2] 0,005 6-MWT (m) 300,0 [261,0; 371,0] 331,0 [280,0; 375,0] 304,5 [253,0; 380,0] 285,5 [246,0; 342,0] 0,006 Right handgrip strength (kg) 28,5 [20,5; 34,0] 31,5 [22,0; 34,0] 29,0 [19,0; 34,0] 27,0 [19,0; 33,0] 0,054 Left handgrip strength (kg) 25,0 [18,0; 31,0] 25,0 [18,0; 32,0] 24,0 [15,0; 31,0] 22,0 [14,0; 28,0] 0,062 * - p-level from baseline data &lt; 0,05 Abstract Figure. dynamics of stimulated muscles


Author(s):  
Wieslaw Blach ◽  
Miodrag Drapsin ◽  
Nemanja Lakicevic ◽  
Antonino Bianco ◽  
Tamara Gavrilovic ◽  
...  

Elite judo athletes undergo vigorous training to achieve outstanding results. In pursuit of achieving competitive success, the occurrence of injuries amongst judo athletes is not rare. The study aimed to perform a knee flexors and extensors isokinetic torque analysis in elite female judo athletes. Fifty-eight elite female judo athletes of the Serbian national team (21.02 ± 3.11 years; 62.36 ± 11.91 kg, 165.04 ± 10.24 cm, training experience 12.72 ± 2.98 years) volunteered to participate in this study. The range of motion (ROM) was set at 90⁰. Testing was performed in a concentric–concentric mode for the testing speed of 60 ⁰/s. Five maximal voluntary contractions of knee extensors and knee flexors muscle groups were measured for both legs. The obtained data showed a statistically significant difference in absolute torque values among different categories as heavier athletes demonstrated higher values. Post hoc analysis showed a significant difference between weight categories, as heavier athletes demonstrated higher values, while no significant differences in normalized torque values for different weight categories were observed. The implementation of new elements and training modalities may improve performance and prevent lateral asymmetry, thus reducing the risk of injury.


2012 ◽  
Vol 6 (1) ◽  
pp. 53-60
Author(s):  
Tomáš Malý ◽  
František Zahálka ◽  
Lucia Malá ◽  
Jaroslav Teplan

Th e aim of the study was to present isokinetic strength profi le of knee fl exors and extensors during concentric contraction in young soccer players. Particularly in knee fl exors was evaluated also strength during eccentric contraction. Research group was state from young soccer players U17 category (n=19, age=16,4±0,3 years). All of them are the participant of highest junior soccer league. Isokinetic strength was evaluated by isokinetic dynamometr Cybex Humac Norm in following angular velocities: 30, 60 and 120°/s in eccentric contraction and 60, 180, 240 and 300 °/s in concentric contraction. Th e results did not revealed signifi cant diff erences at three diff erent speed levels of knee fl exors’ strength during eccentric contraction (p>0,05). Regarding the concentric contraction we found signifi cant diff erences for strength production depending on angular velocity for both knee extensors and fl exors (p<0,01). Knee fl exors generated more strength during eccentric contraction compared to concentric contraction. Th e strength profi les developed in the present study can assist in the establishment of baseline data in young soccer players or for comparison values with other researchers.


2021 ◽  
Vol 15 (1) ◽  
pp. 1-5
Author(s):  
Luciano S. Dias ◽  
Vineeta T. Swaroop ◽  
Luiz R. A. de Angeli ◽  
Jill E. Larson ◽  
Ana-Marie Rojas ◽  
...  

Purpose In myelomeningocele, several classifications have been used. The present manuscript proposes a new functional classification to better assess the prognosis and management of these patients. Methods The manual muscle test is what defines the actual group in which the patient should be included. Furthermore, this new classification brings information about the bracing and external supports recommended to each functional level. We also recommend that the patient’s Functional Mobility Scale should always be mentioned together with their functional level. Results The four levels in this classification are MMFC1, MMFC2, MMFC3 and MMFC4. The MMFC1 group includes patients with significant muscle weakness. They need to use high braces crossing the hip joint with a walker to achieve some ambulation. The MMFC2 group includes patients who have functional hip flexors, knee extensors and knee flexors. However, the hip abductors are quite weak. These patients usually need to use a walker - or crutches - and Ankle-Foot Orthosis (AFOs). The MMFC3 group includes patients with functional hip flexors, knee extensors, knee flexors and hip abductors. However, the ankle plantar flexion function is absent. Most of them are able to walk independently, only using AFOs without any external support. The MMFC4 group includes patients who have preserved function in the entire lower limb musculature. These patients don’t need any assistive devices to achieve an adequate ambulation pattern. Conclusions We hope that this new classification is a system that is simple to understand, serves as a gait prognosis guide and facilitates communication among healthcare professionals. Level of evidence V


1998 ◽  
Vol 8 (3) ◽  
pp. 230-240 ◽  
Author(s):  
JesÚs Rico-Sanz ◽  
Walter R. Frontera ◽  
Paul A. Molé ◽  
Miguel A. Rivera ◽  
Anita Rivera-Brown ◽  
...  

This study examined the nutritional and performance status of elite soccer players during intense training. Eight male players (age 17 ± 2 years) of the Puerto Rican Olympic Team recorded daily activities and food intake over 12 days. Daily energy expenditure was 3,833 ± 571 (SD) kcal, and energy intake was 3,952 ± 1,071 kcal, of which 53.2 ± 6.2% (8.3 g ⋅ kg BW−1) was from carbohydrates (CHO), 32.4 ± 4.0% from fat, and 14.4 ± 2.3% from protein. With the exception of calcium, all micronutrients examined were in accordance with dietary guidelines. Body fat was 7.6 ± 1.1% of body weight. Time to completion of three runs of the soccer-specific test was 37.65 ± 0.62 s, and peak torques of the knee flexors and extensors at 60° ⋅ s−1 were 139 ± 6 and 225 ± 9 N ⋅ m, respectively. Players' absolute amounts of CHO seemed to be above the minimum recommended intake to maximize glycogen storage, but calcium intakes were below recommended. Their body fat was unremarkable, and they had a comparatively good capacity to endure repeated bouts of intense soccer-specific exercise and to exert force with their knee extensors and flexors.


Sign in / Sign up

Export Citation Format

Share Document