bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of axis placement and subject position on measurement of isokinetic peak moment while using the Lido Active Back System
Authors: Amell T.K. , Walmsley R.P. , Narayan Y.
Published: October 2018

{\it Purpose:} The purpose of this study was to assess the effect of varying the measurement axis of the subject relative to an isokinetic dynamometer on the peak flexion and extension moment of the trunk. The effect of testing position (sitting or standing) on peak moment was also investigated.{\it Methods:} Thirty healthy young subjects [8 male, 22 female] were selected at random from a pool of 90 volunteers and asked to perform concentric sagittal flexion-extension cycles at velocities of 60 deg/s, 120 deg/s and 180 deg/s in both the seated and standing position with respect to 5 measurement axes. The subjects were initially aligned with the highest point on the iliac crest(reference axis) and then aligned with 4 measurement axes displaced from the reference axis (25∼mm anterior/posterior and 50mm superior/inferior). {\it Results:} Two-way repeated measures ANOVA revealed significant differences($\alpha < 0.05$) between peak moments recorded between axes and velocity for flexion and extension, however no difference with respect to testing position, i.e., sitting versus standing. Post hoc multiple comparison tests by the Scheff?method revealed that all measurement axes tested were statistically different [$P < 0.001$] from the reference axis, however there were no differences between the two inferior axes [$P = 0.999$] and the two superior axes [$P = 0.982$]. The inferior measurement axes consistently produced greater peak moments than the reference axis while the superior axes consistently produced lower peak moments than the reference axis. Males produced significantly greater peak moments than did females [$P = 0.000$]. {\it Conclusions:} Measurement axis alignment significantly effects the peak moment recorded. Furthermore, these results reinforce the need for accurate and consistent alignment between the subject and the dynamometer. The position of the subject [seated/standing] did not significantly affect the measured peak moment when using the Lido Active Back System in this study.
Mechanomyographic and electromyographic responses of the superficial muscles of the quadriceps femoris during maximal, concentric isokinetic muscle actions
Authors: Cramer Joel T. , Housh Terry J. , Johnson Glen O. , Ebersole Kyle T. , Perry Sharon R. , Anthony J. Bull Anthony J.
Published: October 2018

Eleven adult males (mean $\pm$ SD age $= 22 \pm 3$ years) performed maximal, concentric isokinetic leg extension muscle actions at velocities of 60, 120, 180, 240, and 300 $^{\circ}\cdot$ s $^{-1}$ on a Cybex 6000 dynamometer. The results indicated that peak torque (PT) decreased( $p<0.05$ ) as muscle action velocity increased. Mechanomyographic (MMG) amplitude increased with velocity to 180 $^{\circ}\cdot$ s $^{-1}$ for each muscle tested (vastus lateralis $=$ VL, rectus femoris $=$ RF, and vastus medialis $=$ VM). For the VL, MMG amplitude continued to increase to 240 $^{\circ}\cdot$ s $^{-1}$ and then plateaued, while the RF plateaued from 180 to 300 $^{\circ}\cdot$ s $^{-1}$ . The VM showed a constant increase in MMG amplitude to 300 $^{\circ}\cdot$ s $^{-1}$ . Electromyographic(EMG) amplitude increased to 180 $^{\circ}\cdot$ s $^{-1}$ and then plateaued for each muscle. These findings indicated muscle-specific differences in MMG amplitude patterns across velocity that may be attributable to differences in fiber type composition, muscle architecture, and/or tissue layer composition. Furthermore, these results suggested that there were muscle-specific, velocity-related differences in the association between motor unit activation(EMG) and the mechanical aspects of muscular activity (MMG).
The effect of submaximal eccentric isokinetic training on strength and cross sectional area of the human achilles tendon
Authors: Mouraux D. , Stallenberg B. , Dugailly P.-M. , Brassinne E.
Published: October 2018

This study was designed to investigate the effects of six weeks submaximal eccentric training on concentric and eccentric isokinetic peak torque and cross sectional area (CSA) (muscle and tendon) of calf muscle. Six men and four women volunteered as subjects for this study.

Peak torque values for plantar flexion were determined at 30 $^{\circ}$ /s, 60 $^{\circ}$ /s and 90 $^{\circ}$ /s (concentric and eccentric) using a Cybex $^{\textregistered}$ Norm before the training, 3 weeks after the beginning and at the end of the sixth week.

Following training, peak torque increased in the concentric and eccentric modes in both the trained ( $p<0.001$ ) and untrained( $p<0.01$ ) side. No significant change in CSA was noted.

The results of this study indicate that after 6 weeks of submaximal eccentric training the strength gained was not completely specific to the contraction type used in training. Transfer of training took place. Neither muscle nor tendon hypertrophy was observed, suggesting the involvement of neural adaptation.
The relationship between strength and width of the supraspinatus: An isokinetic and ultrasonographic study
Authors: David Guy , Dvir Zeevi , Simmons Neil , Magarey Mary , Jones Mark , Turker Kernal , Sharpe Margaret
Published: October 2018

Quantitative assessment of supraspinatus (SSp) strength can add substantially to the understanding of the underlying pathomechanics and recovery status of this critically important shoulder joint muscle. Since strength measurement of the SSP is an involved procedure which at times could be contraindicated, obtaining indirect but well correlated evidence in the form of muscle dimensional size may be an alternative method. The objective of this study was therefore to examine the relationship between SSp size and strength in a group ( $n =16$ ) of asymptomatic normal male adults. Strength during rotations, external (ER) and internal (IR), of the shoulder joint was measured using isokinetic dynamometry. The representative morphological dimension of the SSp was its width as calculated from ultrasonographic imaging of the longitudinal cross section. The main findings indicated a moderate to strong correlation with ER strength ( $r=0.65$ to $0.85$ ). In contrast, no parallel association was indicated with respect to IR. Similar patterns were found for the right and left shoulders. It is concluded that ultrasonography of the SSp can furnish valuable information about the strength of this muscle in asymptomatic subjects. However, clinical studies are essential for vindication of this technique with respect to symptomatic shoulders affected mainly with rotator cuff dysfunction.
Isokinetic knee muscle strength of soccer players according to their position
Authors: Tourny-Chollet C. , Leroy D. , Léger H. , Beuret-Blanquart F.
Published: October 2018

The aim of our study was to compare the isokinetic concentric(60\ci.s $^{-1}$ , 120\ci.s $^{-1}$ , 240\ci.s $^{-1}$ ) and eccentric(60\ci.s $^{-1}$ , 120\ci.s $^{-1}$ ) strength bilaterally of the knee muscle of soccer players in relationship to their position on the playing field. The hamstrings and quadriceps strength of 21 soccer players were evaluated with a Kin-Com $\textregistered$ (Kinetic Communicator) isokinetic dynamometer. A predominance of the strength moments on the dominant leg compared to the non-dominant leg was not demonstrated, except for the hamstrings in a concentric mode at a 240\ci.s $^{-1}$ speed. Both the concentric and eccentric strengths of the knee flexors and extensors decreased with the increase in angular speed. The relationship between the three positions in the game (forward, midfield, and defender) and the isokinetic strengths measured at different speeds underlined specific differences between each position. These differences were observed at the level of the co-activation of the knee flexors and extensors during the movements specific to the position and between the kicking leg and the stance leg.
Effects of magnets on concentric and eccentric isokinetic force production of the quadriceps group
Authors: Tis Laurie L. , Trinkaus II Marvin D. , Higbie Elizabeth J. , Johnson Benjamin F. , McCarty Frances A.
Published: October 2018

The purpose of this study was to determine the effects of magnets on concentric and eccentric isokinetic peak and average force production of the dominant knee extensor musculature. All subjects were randomly assessed via isokinetic dynamometry (KinCom 500H, Chattecx Corp.) for concentric and eccentric peak and average force production of the quadriceps in the conditions of magnet, placebo magnet, and control (no magnet). Subjects were assessed at test velocities of 60 and $120$ $^{\circ}$ /s. Twenty-one subjects (age $= 24.2 + 5.1$ yrs, $ht = 174.6 + 8.2$ cm, $wt = 73 + 6.9$ kg) voluntarily participated in the study. Subjects were excluded if they reported a history of knee surgery or sustained a knee injury within the past six months. Two three-way MANOVA's (velocity $\times$ mode $\times$ treatment) were used to determine differences between variables. MANOVA revealed significant differences between test velocities( $p<0.001$ ) and mode of contraction $p<0.05$ ) for peak force production and significant differences between test velocities( $p<0.05$ ) and mode of contraction( $p<0.001$ ) for average force production. MANOVA revealed a significant difference between testing conditions for average force production( $p<0.05$ ). However, Tukey's post-hoc analysis found no significant difference between conditions. Based on the results of this study, application of a magnetic pad to the quadriceps muscles does not appear to increase acute force production. Further research is needed to critically evaluate other purported effects of magnetotherapy.
The test-retest reliability of concentric and eccentric muscle action during plantar flexion of the ankle joint in a closed kinetic chain
Authors: Möller Michael , Lind Karin , Styf Jorma , Karlsson Jon
Published: October 2018

Maximum concentric and eccentric isokinetic plantar flexion peak torque values were evaluated in a closed kinetic chain in eight volunteers from a high-level junior soccer team, with a median age of 17 (range 16--18) years. An isokinetic dynamometer was used and the reproducibility of a previously unevaluated position of the subject was assessed. The test-retest interval was 48 hours. The reproducibility of the test was high, with Intraclass Correlation Coefficients (ICC) of 0.87--0.97 for right- and left-sided concentric and eccentric recordings. The mean peak torque generation was significantly higher in eccentric muscle action compared with concentric; 324 (SD 107) vs 177 (SD 55) Nm. We conclude that one valuable method for measurements of plantar flexion torque in the ankle joint could be in the closed kinetic chain position.
The quantification of reciprocal shoulder strength relation in various working modes at different movement velocities
Authors: Mayer F. , Baur H. , Hirschmüller A. , Heitkamp H.C. , Horstmann T. , Dickhuth H.H.
Published: October 2018

Muscular balance appears to be decisive for dynamic shoulder stability, since passive stabilizers do not take effect until the end of range of motion in order to not limit joint mobility. Changes in strength relationships are frequently viewed as one of the causes of shoulder pathologies. However, objective quantification of reciprocal strength relationships is difficult. In particular, the influence of movement velocity on the strength ratios during the test has not been clarified.

Determination of the strength relationships of reciprocal muscle groups (quotient of maximum torques) was performed on a total of 166 untrained men (M) and 83 untrained women (F) for extension/flexion, abduction/adduction and rotation movements of the shoulder. Moreover, differentiation was made by various working modes and movement velocities (isometric at various angle positions, concentric at 60°/s and 180°/s, eccentric at 60°/s and 120°/s).

The results show a decreasing order of strength relationships: Abduction/Adduction > Flexion/Extension > External/Internal rotation. In spite of marked differences in absolute values, no differences were noted among the contraction modes (isometric, concentric, eccentric) or movement velocities(p>0.05). A slightly reduced ratio of rotational movements in concentric mode was the only conspicuous finding.

Unlike isokinetically-determined absolute torque values, a relevant velocity-dependence must not be expected with respect to reciprocal strength relationships of the shoulder muscles. A different (neuro)-muscular structure of the muscle groups involved with a corresponding effect on the strength-performance ratio thus does not appear to be present or cannot be detected in isokinetic tests. However, further research is warranted regarding the effect of the various associated factors (e.g. stabilization) on the reliability and validity of isokinetic findings relating to this specific joint-muscles system.
The effect of age on isokinetic concentric and eccentric moment of knee extensors
Authors: Bassa E. , Kotzamanidis C. , Patikas D. , Paraschos I.
Published: October 2018

The aim of the present study was to examine the concentric and eccentric isokinetic moment of knee extensors in 108 boys aged 6 to 12 years and in 15 young adults. Participants performed isokinetic concentric and eccentric knee extensions at different angular velocities, 45°, 90° and 180°·s $^{-1}$ . The Ancova designs, using lean mass as covariate, revealed a significant age effect. Post hoc Scheffe test revealed higher moment scores for adults compared to children. Statistical differences between children were observed every two years. Eccentric moments were higher than concentric moments at corresponding velocities. Concentric moments decreased with increasing velocity whereas eccentric moments did not change significantly. Boys were found to achieve almost 40% concentric and eccentric moment of young adults at the age of 12 years. The higher annual increase of both concentric and eccentric moment was observed at 7 years of age.

The present data indicate a gradual and concurrent increase of isokinetic concentric and eccentric moment with age from 6 to 12 years of age suggesting probably a concurrent maturation of contractile and elastic components of the muscle during childhood.
Isokinetic evaluation of hip strength muscle groups in unilateral lower limb amputees
Authors: Croisier J.L. , Maertens de Noordhout B. , Maquet D. , Camus G. , Hac S. , Feron F. , De Lamotte O. , Crielaard J.M.
Published: October 2018

The objectives of the study were to measure the isokinetic strength of the hip flexor-extensor and adductor-abductor muscle groups in unilateral lower limb amputees and to evaluate abnormalities in order to improve the usual rehabilitation programs.

Thirty-three patients with unilateral lower limb amputation were included in this study; they served as their own controls, the amputated side being compared to the intact side. Using an isokinetic device, the relative peak torques (N.m by body weight), bilateral asymmetries and agonist/antagonist torque ratios were calculated for the hip flexor, extensor, adductor and abductor muscle groups.

A significant reduction of mean concentric relative peak torque measured on the amputated limbs was generally observed when compared to the intact contralateral limb (p < 0.05). The mean percentage of relative peak torque decrease was greater for the extensors than for the flexors (33 ± 20% angular velocity), and for the abductors than for the adductors (23 ± 22% Furthermore, the flexor/extensor torque ratio was significantly increased for the amputated limb (for instance, 1.25 ± 0.33> versus 1.09 ± 0.25 for the intact limb at 30°/s). The reduction of the abductor/adductor ratio of the operated limb reached the level of statistical significance at 60°/s only(1.25 ± 0.46 versus 1.07 ± 0.36 for the intact limb).

In conclusion, isokinetic testing revealed a significant reduction of the hip stabilizing muscle strength as a consequence of lower limb amputation. The more marked decrease of the strength of the abductor and extensor muscle groups, resulting in imbalances of the agonist/antagonist strength ratios should be taken into account to adapt the conventional rehabilitation programs.
Different training modes for the rotator cuff muscle group. A comparative study
Authors: Beneka A. , Malliou P. , Giannakopoulos K. , Kyrialanis P. , Godolias G.
Published: October 2018

Thirty six Physical Education students participated in this study and were randomly assigned in three groups: a. The first experimental `isokinetic group' (N=12) followed an isokinetic strengthening program for the rotator cuff muscle group. Its isokinetic exercise protocol consisted of 10 set of 10 repetitions at 90, 120, 180, 210, 240, 240, 210, 180, 120 and 90∼deg/sec respectively, b. The second experimental `MJDR group' (N=12) used the multi joint dynamic resistance training mode for the same muscle group. Its exercise program consisted of four exercises: 1. Pull-ups or lat pull downs, 2. Overhead press, 3. Reverse pull ups and 4. Push-ups (submaximal effort, 8--15 repetitions in 3--7 sets, rest between sets ranging from 2--4 minutes), c. The `control' group (N=12) had no strengthening training. Testing was performed in the supine position with the glenohumeral joint in 900 of abduction in the coronal plane, with a range of motion of 0--900 of external rotation and 0--650 of internal rotation at 60, 120 and at 1800/sec. The testing procedure was performed before and after the exercise period of six weeks. The results showed that in both movements and extremities the performance improvement was not the same for the three groups (interaction 'group' and 'test'). In both internal and external rotation and both extremities, statistically significant improvement in performance was observed only for the two experimental groups.
Effect of isotonic and isometric knee extension exercises on mechanical and electromyographical specificity of fatigue
Authors: Schmitz Randy J. , Arnold Brent L. , Perrin David H. , Granata Kevin P. , Gaesser Glenn A. , Gansneder Bruce M.
Published: October 2018

This study investigated the effects of isotonic and isometric knee extension exercises on strength, power, and surface EMG in male and female populations. Using the knee extensors, ten males and ten females performed a 120 s MVIC and 120 maximal isotonic contractions. Prior to each exercise(t=pre) knee extensor isometric peak torque (strength) and average peak power (power) were tested utilizing three, 3 s MVIC's and three maximal isotonic contractions, respectively. Following each exercise, strength and power were assessed immediately after (t=:00) and at 2.5(t=:02.5), 5 (t=:05), 10(t=:10), and 15 (t=:15) minutes. All strength and power measures were normalized to the respective t=prevalue. Vastus lateralis surface EMG signals were collected during all muscle testing and normalized to the respective t=pre value. Following isometric exercise, both strength and power at t=:00 (68.7%8.7% & 88.0% ± 8.7%) and$t=:02.5$ (82.2% ± 17.8% & 95.2% \pm 5.0%) significantly decreased from t$=$pre (100% ± 0.0%) p<0.05) with greater decreases in strength at each time point (p<0.05). EMG analysis revealed a significant EMG amplitude decrease (p<0.05) att=:00 and t=:02.5 during strength testing with respect to t=pre. Following isotonic exercise, both strength and power at t=:00 (68.0% ± 13.2% & 38.8%± 10.7%) and $t=:02.5$ (84.5% ± 14.9% & 81.6% ± 14.5%) significantly decreased from t$=$pre (100% ± 0.0%) with a greater power decrease at $t=:00$ (p<0.05). The EMG amplitude of males was significantly less at t=:00 than the respective EMG amplitude for females(p<0.05$) (irrespective of testing condition). We conclude that muscle performance in the fatigued state is dependent upon the type of exercise performed.
Conventional vs. dynamic hamstring-quadriceps strength ratios: A comparison between players and sedentary subjects
Authors: Tourny-Chollet Claire , Leroy David
Published: October 2018

The purpose of this study was to determine if the two strength ratios calculated from average strength moments could be different between sedentary subjects and soccer players. The hypothesis was that soccer players would present specific strengths and functional strength ratios. The Hecc/Qcon and Hcon/Qecc ratios are functional ratios and form a means of determining strength in the muscular evaluation of the soccer player. Twenty-one amateur national level soccer players and eleven sedentary subjects were tested for both concentric and eccentric knee extension and flexion strength on the dominant and non-dominant leg with the Kin-Com® isokinetic dynamometer at 3 speeds in concentric contraction (120°·s $^{-1}$ , 60°·s $^{-1}$ and 240°·s $^{-1}$ respectively) and then at 2 speeds eccentrically (120°·s $^{-1}$ and 60°·s $^{-1}$ ). Soccer players present a concentric extensor and flexor strengths significantly higher than that of the sedentary subjects on both the dominant and non-dominant legs. The functional Hecc/Qcon ratio of the soccer players is significantly lower than that of the sedentary subjects at 60°·s $^{-1}$ (0.80 vs. 0.93) and at 120°·s $^{-1}$ (0.88 vs. 1.03) for both legs. In conclusion, the isokinetic evaluation of soccer players and particularly the analysis of the Hecc/Qcon and Hcon/Qecc ratios allow the identification of normative values and can also help to identify potential muscular injuries. Eccentric strengthening exercises can be included in training programs without any risk of altering the specific qualities of the players. The determination of the functional ratios several times during a season could permit the trainer to identify the need for either a collective or individual eccentric strengthening.
Gain in thigh muscle strength after balance training in male and female judokas
Authors: Heitkamp Hans-Christian , Mayer Frank , Fleck Mark , Horstmann Thomas
Published: October 2018

In a previous study, balance training yielded a gain in strength in middle-aged men and women [6]. However, whether such training can yield positive results in highly conditioned athletes has not been addressed. A group of 10 male and 10 female judokas volunteered for a 6-week balance training on rolling boards, pegtops, soft mats and large rubber balls 3 times per week. Pre- and post training of two-legged balance was measured on a stabilometer, one-legged standing time on a narrow rim and bilateral isokinetic strength at 60°/s concentric and eccentric modes, 120°/s concentric mode and isometrically for the knee extensors and flexors. Except for concentric movement at 60°/s in women, significant improvements in strength were indicated. It is therefore concluded that balance training may be useful for both male and female judokas for increasing strength and balance.
The influence of low-frequency electrostimulation and isokinetic training on the maximal strength of m. quadriceps femoris
Authors: Dervisevic Edvin , Bilban Marjan , Valencic Vojko
Published: October 2018

The objective of this study was to examine the influence of isokinetic training and low-frequency electrostimulation in three groups of male athletes (N=20, each group). Three different training methods have been compared: isokinetic training (IT) alone, training with low-frequency electrostimulation (LEFS), and the combination of the two methods. Maximal muscle power was measured before and at the end of the training programs, using a REV 9000 isokinetic dynamometer. The findings indicate that all training methods result in significant increase in muscle strength. However, the largest training effect was due to the combination of IT and LFES.
On the assessment of lower-limb muscular power capability
Authors: Liebermann Dario G. , Katz Larry
Published: October 2018

Purpose: This study assessed the reliability and validity of different methods used to estimate lower-limb muscular power capability based on mechanical variables. For this purpose, vertical jumping was compared with isokinetic knee extensions and with power tests used by practitioners.

Methods: Four groups of subjects (N=106) were tested in different conditions. Group-I performed countermovement vertical jumps (CMJ) on a force plate followed by left and right knee extensions on an isokinetic device at 120, 180 and 240 deg · s $^{-1}$ . Group-II performed CMJ trials followed by 20-m sprints, hand-reach jumps and 1RM leg-press testing. Group-III carried out squat jumps (SJ) in addition to CMJ trials. Finally, Group-IV performed the CMJ test and was retested twice after a short inter-session interval (1–4 days) and after a long one (4.5–5 months). The Pearson correlation was used to assess the validity and reliability of CMJ (p ≤ 0.01, **).

Results: Mean peak power during CMJ was correlated with sprint time(r=-0.882 $^{**}$ ) and leg-press 1 RM(r=0.797 $^{**}$ ), but less with peak hand-reach height(r=0.695; p ≤ 0.05). Isokinetic knee extension power showed also a significant correlation with CMJ power, but its strength depended on the angular velocity (Isok-120 r=0.702 $^{**}$ ; Isok-180 r=0.737 $^{**}$ ; Isok-240 r=0.599 $^{**}$ ). Test-retests showed a strong correlation after a short interval(r=0.915 $^{**}$ ) and after a long one(r=0.890 $^{**}$ ). Using the SJ technique did not have any effect on reliability (r=0.914 $^{**}$ ).

Conclusions: CMJ matches other methods used for testing lower-limb power capability. It is highly reliable and it allows a valid assessment of muscular power. Since CMJ is also simple and accurate to perform, it is the recommended method.
Study of EMG patterns and muscle strength in asymptomatic volunteers during isokinetic flexion-extension movement of the trunk
Authors: Dugailly P.-M. , Mouraux D. , Mangen N. , Brassinne E. , Klein P.
Published: October 2018

Article without abstract.
An update of neck muscle strength: From isometric to isokinetic assessment
Authors: Portero Pierre , Genriès Valérie
Published: October 2018

Pain syndromes in the neck-shoulder region resulting in neck sprain after repetitive mechanical loads imposed on the neck and shoulders during car or sporting accidents do not appear to be an isolated phenomenon. These pathologies require a specific muscle assessment for the diagnosis and the management of patients.

Isometric muscle assessment is classically used, involving a maximal voluntary contraction performed at specified joint position against unyielding resistance. In spite of high reliability and reproducibility, this method does not allow the investigation of the dynamic properties of muscle. For this reason, an isokinetic method has become an increasingly popular modality in rehabilitative and sport medicine. Its concept has the advantage of providing a method of measuring strength during dynamic movements in a highly standardised situation.

Although trunk muscles have been widely explored by the isokinetic technique, the cervical spine has not received the benefit of isokinetic technological progress. Recently, a specific neck device has been designed and validated, permitting the first isokinetic approach of neck muscles in different healthy and sporting populations. This article examines the use of isometric neck muscle assessment and proposes the isokinetic method as a tool for assessing the cervical spine in exercise sciences, medicine, and rehabilitation.
Isokinetic dynamometry of weak muscles
Authors: Tiffreau Vincent , Turlure Alain , Viet Ghislaine , Thevenon André
Published: October 2018

The aims of the study were to assess the reproducibility and validity of very weak knee flexors and extensors muscle strength with a new isokinetic evaluation procedure.

Subjects and methods: Reproducibility mean and maximal work without correction of gravity was first assessed in 14 neuromuscular patients, at 10°/s. Three patients suffering from Guillain-Barre Syndrome were then investigated at different states of recovery. Maximal concentric effort was performed at 10°/s and 30°/s. Acute correction of gravity was performed as forces values measured during passive mobilisation were removed from active measurements. Correlation between manual muscle testing and maximal moment and mean work was explored.

Results: Reproducibility was judged acceptable. Intraclass correlation coefficients ranged from 0.7 to 0.84. In the correlation study, manual muscle assessment ranged from 2 to 4 and peak of forces ranged from 0.4 Nm to 51.88 Nm. There was a significant positive relationship as Spearman Correlation coefficients ranged from 0.77 to 0.89.

Conclusion: Weak muscle isokinetic evaluation is reproducible and well correlated to clinical evaluation. This evaluation procedure could be of great interest in neurological diseases investigations.
Shoulder recentering technique: An isokinetic analysis
Authors: Pocholle M. , Codine P. , Gerardy J.M. , Herisson C.
Published: October 2018

Article without abstract.
Isokinetic dynamometry and electromyographic activity (sEMG) after anterior cruciate ligament reconstruction using semitendinosus and gracilis tendon autografts
Authors: Mouraux D. , Dugailly P.-M. , Brassinne E. , Vancabeke M.
Published: October 2018

Article without abstract.
Isokinetic assessment of knee flexors and extensors in professional soccer players
Authors: Croisier J.L. , Reveillon V. , Ferret J.M. , Cotte T. , Genty M. , Popovich N. , Filho Mohty , Faryniuk J.E. , Ganteaume S. , Crielaard J.M.
Published: October 2018

Article without abstract.
Isokinetic and conventional muscular strengthening in poststroke patients: Preliminary report of a randomised controlled trial
Authors: de Boissezon X. , Burlot S. , Maupas E. , Marque P. , Lemonsu A. , Roques C.F.
Published: October 2018

Article without abstract.
Reproducibility of concentric and eccentric isokinetic strength of the shoulder rotators in normal subjects 40 to 55 years old
Authors: Dauty Marc , Delbrouck Claire , Huguet Dominique , Rousseau Bertrand , Potiron-Josse Michèle , Dubois Charles
Published: October 2018

The purpose of this study was to define the test-retest reproducibility of concentric and eccentric isokinetic measurements of shoulder rotators. It was carried out at a 26 day ± 4 interval. Fourteen healthy volunteer subjects (7 men and 7 women), aged between 40 and 55 years (47.5 ± 5.6 years), were included. Evaluation was carried out with a Cybex Norm dynamometer and the reliability was calculated according to the intra-class correlation coefficient (ICC 2.1). The protocol was randomised for the shoulder and for sets of concentric (con) and eccentric (ecc) tests. Concentric sets consisted of 5 movements of internal (IR) and external rotation(ER) at the speed of 60°/sec. then 120°/sec. Eccentric performance was recorded only for the external rotators, to determine the ratio ER $_{ecc}$ / IR $_{con}$ . Results indicated excellent reproducibility for the peak torque (0.91–0.98), total work (0.88–0.96) and average power(0.83–0.94) in concentric muscle action for internal and external rotators and in eccentric muscle action for external rotators at 60 and 120°/sec. On the other hand the strength ratio: ER $_{con}$ / IR $_{con}$ and ER $_{ecc}$ / IR $_{con}$ should be interpreted with caution because of a lower reproducibility (ICC: 0.53–0.83).

In conclusion, isokinetic findings relating to concentric and eccentric performance of the internal and external rotators of the shoulder are reproducible under the present protocol. These findings may serve for assessing rotator cuff function at the age where the incidence of rotator cuff overuse becomes a serious problem.
Force-velocity relationship of the wrist flexors and extensors: The influence of small and large handgrips
Authors: Poulis S. , Rapanakis P. , Pastra X. , Poulis I. , Soames R.W.
Published: October 2018

Isokinetic concentric and isometric contractions of the wrist flexors and extensors were recorded from 40 young males using a Cybex II+ isokinetic exercise system using handgrips of 4 cm and 8∼cm diameter: the isokinetic recordings were obtained at velocities of movement of 45°/s, 90°/s and 180°/s. For both muscle groups peak torque and work done both decreased with increased velocity of contraction, however average power increased. The wrist flexors generated significantly(P < 0.01) greater peak torque, work and average power than the extensors, with the extensor/flexor ratio for peak torque being 0.57. No differences were observed between the dominant and non-dominant wrist, or between the size of handgrip used.
Reliability of isokinetic concentric and eccentric knee and elbow extension and flexion in 9/10 year old boys
Authors: Deighan M.A. , De Ste Croix M.B.A. , Armstrong N.
Published: October 2018

The aim of this study was to determine the reliability of measures of concentric and eccentric extension and flexion peak moment of the knee and elbow of prepubertal boys. Twenty boys volunteered for the study. Ten performed the knee test and ten performed the elbow test. All subjects were permitted a separate day familiarisation session and were later tested on two separate occasions, exactly 1 week apart, at the same time of day and with the same test administrators. Peak moment was measured with an adapted Biodex System-3 using continuous concentric-concentric and eccentric-eccentric cycles at 30°/s and 180°/s. The reliability measures were intraclass correlation coefficient (ICC), repeatability coefficient (RC), limits of agreement (LOA) and coefficient of variation (CV). ICCs ranged from 0.55 to 0.97 and CV ranged from 4% to 15%. There was no systematic difference in peak moment between test and retest. The various indices demonstrated moderate to high reliability of peak moment measurements in this age group which compared favourably with the existing literature. The results of the study support the reliability of measures of concentric and eccentric peak moment in studies of children's strength.
Age-related changes in concentric and eccentric muscle strength in the lower and upper extremity: A cross-sectional study
Authors: Delbaere K. , Bourgois J. , Witvrouw E.E. , Willems T.M. , Cambier D.C.
Published: October 2018

Objective: To determine the influence of ageing on lean muscle area and isometric and concentric and eccentric muscle strength in the upper and lower extremity in a cross-sectional study design.

Subjects and methods: Lean muscle area and maximal muscle strength(isometric and isokinetic, 60° and 120°/s) of both upper and lower extremity were assessed of 45 men and 56 women (20 to 89 years).

Results: One-way variance analysis and regression analyses revealed a parallel decline with age in both sexes for maximal muscle strength. The decline in maximal muscle strength from age 60 was 34 to 45% in men and 11 to 32% in women in the arms and 40 to 47% in men and 37 to 45% in women in the legs. Isometric, concentric and eccentric contractions showed a similar decline in ageing in both sexes. There was a better maintenance with age of the strength in the arms than in the legs (p < 0.01) and at 120°/s than at 60°/s(p < 0.05).

Conclusions: The present findings suggest a parallel decline in lean muscle area and strength and similar losses in isometric, concentric and eccentric strength with increasing age.
Manual massage effect in knee extensors peak torque during short-term intense continuous concentric–eccentric isokinetic exercise in female elite athletes
Authors: Sykaras E. , Mylonas A. , Malliaropoulos N. , Zakas A. , Papacostas Em.
Published: October 2018

Manual massage is considered an important part of athletic rehabilitation or preparation for training and competition.

Objective: To study the possible effects of manual massage on concentric and eccentric peak torque of knee extensors, when applied during intervals of exercise.

Methods: Twelve elite female Tae Kwon Do athletes were tested twice during a week (different extremity each) in continuous concentric/eccentric isokinetic exercise (6 sets of 10 repetitions, with 2 minutes intervals). Manual massage was applied during breaks to the extremity (massage extremity) while for the other limb (control extremity) the interval was passive. For both groups peak torque was measured 3 minutes after the last set. The same test was performed 3 minutes prior to the first set. The best performance was recorded pre- and post-exercise and the results were compared.

Results: For both groups peak torque (concentric and eccentric) was reduced after the exercise protocol. In the massage group the reduction was lower and significantly different for eccentric type of muscle work (p < 0.05).

Conclusions: Application of manual massage during isokinetic exercise intervals has an enhancing effect on the peak eccentric torque of the knee extensors.
The relationship between lean body mass and isokinetic peak torque of knee extensors and flexors in young male and female swimmers
Authors: Mameletzi D. , Siatras Th. , Tsalis G. , Kellis S.
Published: October 2018

In sprint swimming, thigh muscles strength and body composition may contribute to the development of a good performance in the water. The present study describes the relationship between lean body mass (LBM) and isokinetic peak torque (PT) of knee extensor and flexor muscles in male (n = 31) and female (n = 22) competitive swimmers aged 10 to 12 years. Skinfold thickness measurements for percent body fat and LBM were recorded. Isokinetic testing consisted of concentric knee extensions and flexions at 60°/s, 120°/s and 180°/s. High correlation coefficients (Pearson's r: 0.765–0.890, p < 0.001) indicated a strong relationship between LBM and knee muscles strength at all angular velocities. Using linear regression analysis, PT could be predicted from the LBM for this particular age and sex groups. However, a simple linear model between LBM and PT could not be constituted as complementary biological parameters, such as flexibility and muscular endurance could also account for the variability.
Different training programs for improving muscular performance in healthy inactive elderly
Authors: Malliou P. , Fatouros I. , Beneka A , Gioftsidou A. , Zissi V. , Godolias G. , Fotinakis P.
Published: October 2018

The purpose of the present study was to determine whether a general conditioning (callisthenic exercise) versus a machine based resistance-training protocol or an isokinetic exercise program would be similarly effective in improving knee extension muscular performance in healthy inactive elderly. Fifty two individuals, 26 men and 26 women, were randomly assigned to one of four groups: control group (C, n=10), the isokinetic strengthening group (ISO, n=12), the multi-joint resistance training group (RES, n=15) and the calisthenic exercised group (CAL, n=15). The training protocol for the ISO included concentric isokinetic extension and flexion of the knee, for the RES included leg extension, leg curls and leg press and for the CAL included aerobic exercise accompanied with music, general calisthenics and activities targeted to reaction time and agility improvement. The isokinetic concentric testing method applied prior to and at the end of the training period to assess peak muscle torque of the right knee extensors. MANOVA repeated measures (2× 4, time by treatment) revealed that at 60°/s angular velocity there was statistically significant improvement in performance for the RES group in comparison to control group. At 180°/s angular velocity the results revealed, statistically significant improvement in performance for the RES and ISO group also. In conclusion, in older adults isokinetic exercise and resistance training results in larger increases in strength compared with callisthenic exercise.
Evaluation of force-speed parameters of the trunk muscles in idiopathic scoliosis
Authors: Skrzek A. , Anwajler J. , Mraz M. , Woźniewski M. , Skolimowski T.
Published: October 2018

The aim of this research was to assess the characteristics of strength-velocity parameters of the trunk muscles in girls with idiopathic scoliosis vs. controls. Isokinetic evaluation of spinal flexors and extensors for both groups consisted of concentric testing at 90 and 120°/s and an additional test at 60°/s and endurance testing in the experimental group only. Girls with scoliosis had significantly lower strength parameters but performed better with respect to velocity parameters. The findings indicate large limitations of functional capacity of trunk muscles in girls with a diagnosed idiopathic scoliosis.
Plantar flexor muscle action while sitting, standing and prone in patients with upper motor neuron lesion due to stroke
Authors: Carlsson U. , Henning G.-B. , Svantesson U. , Sunnerhagen K.S.
Published: October 2018

Aim: The purpose of the present study was to investigate the effect of different test positions on the static strength of ankle joint muscles and the EMG activity of the calf and thigh muscles in patients with upper motor neuron lesion due to stroke.

Set-up: Static torque was recorded during isometric plantar flexion muscle action while sitting, standing and lying prone, in both the affected and the non-affected leg in seven patients. The EMG activity was recorded in the soleus, medial gastrocnemius, anterior tibial and rectus femoris muscles.

Results: The affected leg showed lowered torque values in all positions compared to the non-affected leg. There were no significant differences in the torque values depending on positions nor in the EMG recordings. When the standing position was used as "normative", there was a significant difference in the EMG values between the affected and non-affected leg when sitting with the knee bent and while standing with the knee straight; i.e. in closed-chain exercises.

Discussion: Training and testing of strength in the plantar flexor muscles in stroke patients may be done in both open and closed-chain exercises as far as force development is concerned. However, the outcome of these different types of exercises might be influenced by the position of the knee joint since the gastrocnemius is a two-joint muscle.
Effects of dominance, body mass index and age on grip and pinch strength
Authors: Ertem Kadir , Inan Muharrem , Yologlu Saim , Elmali Nurzat , Harma Ahmet , Sahin Sükrü , Bora Arslan
Published: October 2018

Measurement of grip and pinch strength is an important component in hand evaluation. It assesses the patient's initial limitations and provides a quick reassessment of patient's progress throughout the treatment. This investigation was conducted to examine the effects of hand dominance, body mass index (BMI) and age on grip strength (GS) and pinch strength (PS) tasks. Subjects were 365 apparently healthy young male adults (19–33 years). No correlation was found between the BMI hand strength measures. Grip and pinch strength were measured instrumentally. The rule "dominant hand (DH) is approximately 10% stronger than the nondominant hand (NDH)" was found to be valid for left handed persons only (11.2%), otherwise these measures should be considered equivalent in both hands in clinical practice.
Intramachine and intermachine reproducibility of concentric performance: A study of the Con-Trex MJ and the Cybex Norm dynamometers
Authors: Bardis C. , Kalamara E. , Loucaides G. , Michaelides M. , Tsaklis P.
Published: October 2018

Introduction: There is minimal information in the literature concerning the intramachine reliability of the new Isokinetic dynamometer Con-Trex MJ, and the intermachine reproducibility of this instrument with the Cybex Norm isokinetic dynamometer.

Objective: The purpose of this study was to provide some insight with regard to the reproducibility of Con-Trex MJ in measuring the knee muscle performance in flexion and extension (concentric) and to compare the variability of measurement between Con-Trex and Cybex Norm.

Methods: 35 (70 legs) male subjects with no previous history of any knee pathology volunteered for the study. Intramachine reproducibility was evaluated by assessing 30 legs twice on the Con-Trex MJ, within 2 to 7 days, at angular velocities of 60°, 180° and 300°/sec. Intermachine reproducibility was evaluated by assessing 40 legs randomly on the Con-Trex MJ and Cybex Norm within 2 to 7 days at 60° and 180°/sec. Coefficient of variation (CV) was used to determine the reproducibility of repeated measurements at $p< 0.01$. Results: Intra: The variability of measurements of Con-Trex for Peak Torque, was 5.19–5.68% for extension and 4.84–7.33% for flexion depending on the angular velocity. This is acceptable for clinical and research studies. Inter: Between the two Isokinetic devices there was a greater CV for Peak Torque ranging 7.28–9.17% for extension and 8.54–15.84% for flexion.

Conclusion: Based on the results of the present study, comparisons of results between the two devices may not be valid. The results for knee flexion and extension measurements at 60° and 180°/sec recorded with Con-Trex were consistently greater than the values recorded with the Cybex Norm.
Muscular force-velocity parameters during single joint and multiple joint sagittal activities of the upper limb
Authors: Stefańska Małgorzata
Published: October 2018

Objective: To determine the force-velocity characteristics (F-v) of upper limb muscles and specify the muscle group which has a predominant influence on the global F-v characteristics of the limb.

Subjects and methods: 30 healthy young men participated in this study which consisted of two experiments. In the first the moment developed by flexors and extensors of shoulder, elbow and radio-carpal joints at angular velocities ranging 0–300°/s was measured isokinetically. In the second experiment global F-v characteristics were assessed statically and dynamically.

Results: Elbow extensors had a predominant impact on the shape of the global F-v characteristics of the examined limb.

Conclusions: The force-velocity characteristics provide comprehensive information regarding the capacity of the examined muscle groups. This information is of value in setting target scores for total upper limb strength in the context of specific habitual activities such as chair rise.
Isokinetic performance and shoulder mobility in Taiwanese elite junior volleyball players
Authors: Wang Hsing-Kuo , Juang Lin-Guey , Lin Jau-Jia , Wang Tyng-Guey , Jan Mei-Hwa
Published: October 2018

The objective of this study was to determine whether arm dominance or gender differences of shoulder mobility and strength exist in elite junior volleyball players. The range of shoulder motion and isokinetic muscle strength in concentric and eccentric internal and external rotation at speeds of 60°/sec and 180°/sec in both dominant and non-dominant shoulders were measured in eleven boys and twelve girls who played for the Taiwanese national junior volleyball team during the 2001–2002 season. Results showed that there were effects of both dominance and gender on the range of shoulder internal rotation p=0.001 and 0.02 respectively). In the boys, the range of motion of internal rotation on the dominant side was less than that of the non-dominant side (p=0.000). An effect of gender was also demonstrated in the strength test (p=0.000). The boys showed greater shoulder strength than the girls at both speed tests(p=0.000), except for the internal rotational concentric and eccentric strength of the dominant arm at 180°/sec tests (p=0.02 and 0.21). The side-to-side (arm dominance) difference of mobility in boys may indicate a mobility loss in these players. Further studies are suggested to analyze the relationship between mobility loss and mobility-related injuries of young players.