bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isokinetic cross-training effect in foot drop following common peroneal nerve injury
Authors: Manca Andrea , Pisanu Francesco , Ortu Enzo , De Natale Edoardo , Ginatempo Francesca , Dragone Daniele , Leali Paolo Tranquilli , Deriu Franca 
Published: October 2018

BACKGROUND: To our knowledge, no studies on foot drop (FD) caused by peripheral nerve lesion have investigated whether unilateral training of the unaffected ankle dorsiflexors induced a clinically meaningful strength improvement in the affected-untrained leg, namely a cross-training (CT) effect. METHOD: A 59-year-old man, who suffered since childhood from surgically-induced damage of the common peroneal nerve, performed an 8-week maximal-intensity isokinetic training of the healthy leg. Before and after training, patient underwent: bilateral isokinetic testing; functional and mobility tests including 6-minute walking test, 10-meter walking test, timed-up-and-go test and ankle ROM; neurophysiological recordings including motor thresholds, cortical silent period of the hemisphere innervating the affected tibialis anterior and mean EMG recruitment. RESULTS: After cross-training, the affected-untrained dorsiflexors showed notable increases in all dynamometric parameters. Similarly, all functional tests improved considerably. The cortical silent period was reduced and the maximal EMG recruitment increased. CONCLUSIONS: Improvements in muscle performance and neurophysiological drive in the affected non-trained limb due to training of the unaffected side indicate that cross-training may be a viable rehabilitative approach to foot drop.
Shoulder girdle protraction strength and dynamic performance of the upper limb in individuals with scapular winging: \newline A preliminary study
Authors: Kim Yang-Gon , Kang Min-Hyeok , Kim Ji-Won , An Duk-Hyun , Oh Jae-Seop 
Published: October 2018

BACKGROUND: Although strength exercises for shoulder girdle protraction (SGP) have been emphasized in subjects with scapular winging, few experimental studies have SGP strength measured this function in this cohort. OBJECTIVE: To compare SGP strength and performance of the upper quarter closed-kinetic-chain in healthy subjects and patients with scapular winging. METHODS: Twenty-six men (13 patients with scapular winging, 13 controls) exerted maximal isometric SGP force against a force-measurement device while the upper quarter Y-balance test was conducted to examine the performance of the upper quarter closed-kinetic-chain using a Y-balance kit. RESULTS: The SGP strength in the patient group was significantly lower than that of the control group (p=0.001) while the scores on the Y-balance did not differ between the groups. The correlation between strength and motion of the upper limb during performance of upper quarter closed-kinetic-chain was relatively low (r=0.394, p=0.046). A sensitivity analysis has indicated that based on the extreme values of the patient group (the maximal individual SGP strength score) and the control group (the minimal individual strength score), 4 of the patients and 8 of the healthy participants, would have been categorized as uninvolved (false negatives) and involved (false positives), respectively. However based on the mean SGP strength score, only one patient crossed into the control subjects distribution while none of the control subject have crossed into the patients distribution. CONCLUSIONS: These findings indicate that although scapular winging may be associated with SGP weakness, particularly in cases where the isometric force is less than 130 N. However, great care has to be taken in interpretation of findings while further research should be encouraged.
Isokinetic and isometric torque values using a Kin-Com dynamometer in normal subjects aged 20 to 69 years
Authors: Phillips Beverley A. , Lo Sing K. , Mastaglia Frank L. 
Published: October 2018

{\it Objective:} To obtain normal torque values for the knee extensors and flexors using a Kin-Com dynamometer in a large group of normal subjects. {\it Design:} We used a Kin-Com dynamometer to measure the isokinetic torque at 60 and 120 deg/sec and isometric torque of the knee extensors and flexors in a sample of 200 normal subjects aged 20 to 69 years. {\it Results:} Reliability coefficients for average and isometric torque were >0.82 for both intra- and inter-session reliability. Male subjects exerted a significantly greater isokinetic and isometric torque than female subjects for both muscle groups and age was a significant predictor of torque for all tests. The 5th percentile values, as the lower limit of normal, are reported separately for gender and side of testing for each decade of age, and may be used for comparison to patient data providing that the specified testing protocol and a Kin-Com dynamometer are used.
Lower-limb extension power: How well does it predict short distance speed skating performance?
Authors: Liebermann Dario G. , Maitland Murray E. , Katz Larry 
Published: October 2018

{\it Purpose:} This study was aimed to explore the relationship between lower limb extension power measured by isokinetic knee extensions (IK) and vertical jumps performed on a force plate (VJ) and speed skating (SS) sprint power measured by a laser device. {\it Methods:} Twenty elite short- and long-track speed skaters performed 100 m sprints followed by VJ and IK trials. Power-time curves were calculated off-line. Pearson correlation coefficients were used to determine the degree of association between the variables. {\it Results:} SS sprint power correlates strongly with VJ power(r=0.870; p<0.001) while IK power showed a weaker but significant correlation to both (r=0.707 and r=0.706, respectively; p<0.01). As expected, SS times at 15 m and 100 m were inversely associated with SS sprint power (r=-0.818 and r=-0.909; p<0.001) and VJ power (r=-0.730 and r=-0.763; p<0.001), and to a lesser degree with IK power (r=-0.602; r=-0.618; p<0.01). {\it Conclusion:} The analyses differentiate between methods of estimating power in speed skaters, and show a strong relationship between initial SS performance and muscular power. Given that 100 m split times strongly relate to final 500 m results (r=0.972; p<0.001, N=332), it is reasonable to believe that an initial power and a stable peak speed before the first curve may lead to achieving the winning edge in short SS events. A finding of particular interest is that isokinetic power results are correlated significantly with the practical outcomes of the performance in spite of the high specificity of the isokinetic testing method.
Identification of previous hamstring muscle injury by isokinetic concentric and eccentric torque measurement in elite soccer player
Authors: Dauty Marc , Potiron-Josse Michèle , Rochcongar Pierre 
Published: October 2018

Twenty-eight elite soccer players (23 years ± 3.3; 74 kg ±7.5; 178 cm ± 6.5) were tested to find out whether isokinetic parameters could identify sportsmen who had previously suffered from hamstring muscle injury. Eleven players with 15 previous moderate or major hamstring muscle injuries in the preceding 2 years were compared with 17 controls. Strength was measured using a Cybex Norm isokinetic dynamometer on a concentric and eccentric contraction at the angular speed of 60°/s. An ipsilateral concentric Hamstring-to-Quadriceps ratio lower than 0.6 and an eccentric hamstring asymmetry of more than 10% did not enable identification of soccer players with previous hamstring muscle injury. On the other hand, concentric hamstring torque asymmetry of more than 10% identified the uninjured soccer players (probability of 90.1%). A dynamic control ratio(eccentric hamstring-to-concentric quadriceps) lower than 0.6 provided the best predictor of previous hamstring muscle injury (probability of 77.5%). In conclusion, concentric and eccentric isokinetic evaluation of hamstring muscle at the speed of 60°/s renders the search for previous hamstring muscle injury possible by revealing muscle torque asymmetry, which persists despite the resumption of competitive soccer.
Functional and isokinetic assessment of hands with early stage of Rheumatoid Arthritis
Authors: Poulis S. , Kretsi Z. , Apostolopoulos L. , Zeeris H. , Vagenas G. 
Published: October 2018

The objective of this study was twofold: to explore the effect of RA on hand grip strength at early stage of diagnosed RA and to support the application of isokinetic evaluation in the assessment of RA. Twenty women, age 48 ± 5 years, participated in this study: 10 with early stage RA and 10 healthy controls. The evaluation tests were included the Health Assessment Questionnaire (HAQ), Moberg pick up test, range of motion (ROM) of the wrist, grip strength, pinch strength, visual analogue pain scale (VAPS) and isokinetic evaluation of concentric and eccentric strength of the wrist flexor and extensor muscles. The statistical analysis showed no differences in ROM, grip and pinch strength and in the isokinetic evaluation measurements between the two groups. The HAG showed that women with early stage RA have no difficulty in performing daily activities, and there was an increase of completion time due to loss of optical control in the Moberg pick up test in both groups. In conclusion, women with early stage RA do not present with any significant impairment as indicated by the above-mentioned tests.
Training and testing in open versus closed kinetic chain
Authors: Mayer F. , Schlumberger A. , van Cingel R. , Henrotin Y. , Laube W. , Schmidtbleicher D. 
Published: October 2018

Optimization of different forms of training and testing in sports and therapy has traditionally been debated by various groups. Especially, the use of so-called open and closed kinetic chain exercises has frequently been a focal point. Scientific studies have indicated that no specific form of exercise and/or training has any particular advantage over the other. This applies to both assessment of efficiency, consideration of compression and shear forces, muscular activity and the extent of co-contractions. Unlike the broadly-applied non-specific and uncritical assessment of open and closed kinetic chain exercises, a specific application using the advantages of both procedures must be considered due to clinical, therapeutic and training-physiological aspects. Specificity refers to the training of either an isolated joint-muscle unit(arthron) or a system (group) of joints and muscles. Considering the original definitions and past misinterpretations, it appears logical to emphasize the role of physiological mechanisms operating in each form of training and testing. Therefore, the use of the term: single-joint(SJ) or multi-joint (MJ) training, is recommended since this would best reflect the area of application, according to a recent consensus expressed by EISCSA. Consequently, SJ and MJ exercises should be applied both in isolation and in combination as indicated by the principles of specificity. On the other hand, continuous use of the terms open and closed kinetic chain exercises is confusing, erroneous, leads to polarizing discussions and should hence be relegated to the past.
Isokinetic measurements of calf muscle stiffness following fatiguing exertion
Authors: Svantesson U. , Carlsson U. , Grimby G. 
Published: October 2018

Objective: To determine the influence of fatigue on active and passive muscle stiffness when the muscle/tendon complex has been exposed to high-intensity dynamic exercises of a short duration. Subjects and methods: Fifteen (see: Methods: 2.1 subjects) healthy women aged 23 ± 2 years participated. Active and passive stiffness of the calf muscle was measured on an isokinetic dynamometer using electrical stimulation and passive stretch (200°/s). The stiffness test was conducted before and immediately after high-intensity dynamic exercises of the plantar flexors performed until exhaustion. Results: The forces generated by the same electrical stimulation level were significantly higher before than after the fatigue test. No significant changes could be demonstrated regarding active or passive stiffness before and after the fatigue protocol. However individual changes in active stiffness of about 40% were noted. Conclusion: Even though no significant changes in stiffness were apparent after the fatiguing exertion large individual changes could be noted. This is an indication that stiffness in the calf muscle after high-intensity dynamic exercises may not correspond to the peripheral fatigue.
Isokinetic dynamometry in assessment of external and internal axial rotation strength of the shoulder: Comparison of two positions
Authors: Hill A.M. , Pramanik S. , McGregor A.H. 
Published: October 2018

Background: Measuring isokinetic strength of the shoulder complex is potentially an important clinical tool in both diagnosis and management of injury and pathology. However, a clinically relevant position is yet to be established. Objectives: To establish an appropriate and repeatable protocol to evaluate the functional strength of both internal and external rotators of the glenohumeral joint to enable assessment of clinical injury management and training related developments in upper limb strength. Methods: A population cross-sectional study of shoulder internal and external rotational strengths of 17 normal, healthy volunteers (11 males, 6 females) aged 21 to 45 years were measured both isokinetically and isometrically. Two test positions: seated and supine, were compared by way of reliability and repeatability analyses. Humeral rotation was performed at 45° of abduction in the scapular plane seated, and at 90° of abduction in the supine position. Results: Throughout concentric testing, when the population was considered as a whole the left shoulder data appeared more repeatable than the right shoulder. This however, was not evident when the study population was divided into single sex groupings. Equally, whilst the repeatability trend of sitting vs. supine position was skewed towards the former, more evident in the left shoulder, this was less apparent when sexes were analysed separately. All comparative measures were statistically insignificant. Conclusion: The findings of this study suggest that measurements of isokinetic shoulder rotation strength are highly prone to both joint specific and non-specific errors.
Plantar arch type and strength profile of the major ankle muscle groups: A morphometric-isokinetic study
Authors: Cubukcu Sibel , Alimoglu M. Kemal , Balci Nilufer , Beyazova Mehmet 
Published: October 2018

Purpose: To determine the effect of foot arch structure on ankle muscle strength. Methods: Forty-seven young female volunteers (94 feet) were classified in to low (LA), high (HA) and normal (NA) arch groups according to their arch ratio (AR) and Chippaux-Smirak index (CSI) values. The distribution of the participants among LA, HA and NA groups did not differ when AR or CSI was preferred for classification. Isokinetic muscle strength of ankle invertor/evertors and plantar/dorsal flexors was measured by using an isokinetic dynamometer. One-way ANOVA, Pearson correlation test and ROC curve analysis were used in statistical analyses. Results: A strong correlation was found between AR and CSI values. Significant differences were found in mean strength measurements of ankle muscles in favor of NA group at 120°/s for dorsiflexion and plantar flexion, 120 and 150°/s for eversion and at 120°/s for the ratio between ankle inversion and eversion. Sensitivity and specificity rates of muscular strength as an indicator of arch anomalies were low. Conclusion: Normal arched individuals have higher muscular strength values only at faster testing speeds
Reproducibility of trunk isokinetic strength findings in healthy individuals
Authors: Dervišević Edvin , Hadžić Vedran , Burger Helena 
Published: October 2018

Background. Back strength is an important factor in the functional assessment of chronic low back patients and therefore ensuring the reproducibility of the findings is of critical importance. So far the studies were focusing on relative indices that turned out to be an inappropriate method due to possibility of bias. Furthermore the reproducibility of eccentric trunk flexors strength findings that may play a role in numerous sport activities has never been evaluated. Objective. To evaluate the reproducibility of isokinetic eccentric and concentric strength of the trunk flexors and extensors in healthy subjects using the absolute reproducibility indices. Methods. Twenty seven young healthy physical education male students were tested twice over a period of one week using an isokinetic dynamometer. The main outcome measure was isokinetic peak torque. Results. Strength scores of the trunk flexors and extensors evidenced clinically acceptable reproducibility. This conclusion was valid irrespective of the testing velocity or type of contraction. Conclusion. Concentricand eccentric isokinetic testing of the trunk flexors and extensors muscles is a viable option for the testing of healthy subjects.
Isokinetic findings in scoliosis: Their relationship to clinical measurements and reliability studies
Authors: Blay Grègoire Le , Atamaz Funda , Biot Bernard , Calmels Paul , Mouilleseaux Brigitte 
Published: October 2018

This study assessed the applicability of dynamometric muscle evaluation in scoliosis. Objective: To assess the clinical applicability of the dynamometric muscle evaluation in scoliosis by reliability studies, its relations with the clinical measures, and comparison analysis with healthy subjects. Methods: Thirty five scoliotic female patients and 27 healthy women were evaluated dynamometrically muscle strengths, additionally the scoliotic women were evaluated by clinical measures. To assess the reliability of isokinetic muscle testing 20 scoliotic women were tested twice 1 week apart Results: The ICCs ranged 0.81–0.96, except in the case of the knee extensor strength at 120°/s. Curve angle was weakly correlated to trunk flexor strength at 90°/s (r=0.40), the curve pattern was moderately related to knee muscles' strengths (−0.46 < r < −0.57). Scoliotic women showed weaker isokinetic muscles strengths except the trunk extensors at 90°/s. Conclusion: Isokinetic evaluation of trunk muscle strength may be an additional tool in assessing this patient group.
Development of a protocol for isometric trunk rotational strength testing and strength asymmetry assessment
Authors: McIntire Kevin , Asher Marc , Burton Douglas , Liu Hongzeng , Liu Wen 
Published: October 2018

A standardized protocol for assessing trunk rotational strength symmetry has not been established. Opposing muscle (agonist/antagonist) strength ratios have been used to assess strength asymmetry of appendicular joints but not the asymmetry of trunk rotational strength. The purpose of this study was to develop a protocol for measuring isometric trunk rotational strength with proper data analysis to assess rotational strength asymmetry. Methods: Maximum isometric trunk rotational strength of twenty healthy young adults, 12 women (25.1 ± 3 years), 8 men(30.1 ± 5.6 years), was measured at 5 positions of trunk rotation on two different days by two different testers. Strength asymmetry was assessed in several ways including F-tests, percent-differences, and strength ratios. Results: Trunk strength was symmetrical at neutral and 18° testing positions. In the 36° pre-rotated trunk positions, right contractions toward neutral tended to be stronger than left contractions; whereas left contractions away from neutral tended to be stronger than right contractions. Conclusions: Our findings suggest caution when interpreting asymmetry at the 36° pre-rotated position. These methods of testing and assessing rotational strength asymmetry may be useful in patient populations in which strength asymmetry is hypothesized.
Field performance of javelin throwers: Relationship with isokinetic findings
Authors: Forthomme B. , Crielaard J.M. , Forthomme L. , Croisier J.L. 
Published: October 2018

Published data related to javelin throwers remain poorly documented. The objectives of this study were therefore to compare isokinetic strength profile of the shoulder rotator muscles between javelin throwers and sedentary persons and to correlate isokinetic data with different field performance parameters. Eleven male javelin throwers and ten sedentary subjects participated in the study. Shoulder internal (IRs) and external rotators (ERs) were isokinetically assessed at 60, 240 and 400°/s in concentric and 60°/s in eccentric exertions. Subjects also performed throwing tests successively using a javelin and a ball (both of 800 g mass). Side to side comparison in the throwers group revealed a dominance effect in the concentric mode for the IRs at all speeds, and for the ERs at 240°/s. Sedentary subjects showed a dominance effect for the IRs at 60°/s and 240°/s. Simple isokinetic concentric-concentric ratios and mixed velocity DCRs (eccentric60/concentric240) of the dominant shoulder were significantly lower in comparison to the non-dominant side values, in the throwers population. Only the simple ratio at 400°/s and the mixed ratio were significantly lower in the sedentary subjects (dominant versus non dominant side). With respect to the dominant shoulder, no significant difference was noted between the groups the peak torque was bodyweight normalized. However, throwers showed a significant reduction of the DCR when compared to the control group. In addition, throwers exhibited moderate to strong correlations (0.61⩽ r ⩽ 0.89) between IRs and ERs strength and either the javelin throw test or the personal throwing record. For the sedentary subjects the javelin throw test was correlated only with the IRs concentric strength at 240°/s. In conclusion, javelin throwers showed a significantly reduced mixed ratio in comparison with a control group, even though body weight normalized peak torques did not differ between both populations. Significant correlation was established between rotator peak-torques and javelin throw test among the thrower athletes. Although training program in thrower athletes classically focuses on IRs strengthening, our findings strongly suggest the need for ERs performance improvement.
Time course of trunk extensor muscle fatigue as measured using dynamometry and electromyography
Authors: Abdalla Sala , McGregor Alison H. , Strutton Paul H. 
Published: October 2018

Poor trunk extensor endurance is implicated in low back pain, less is known regarding contributions of different regions of the erector spinae to maximum torque production particularly after fatigue. This study examines torque and electromyographic (EMG) activity following a maximal voluntary contraction (MVC) hold in these muscles. 16 students (9 male, 7 female, mean age 21.3 ± 0.6 years) participated. Testing was performed using a Cybex isokinetic dynamometer with synchronous bilateral EMG recordings(during MVCs of 5 second duration) from the left and right the erector spinae(ES) muscles at vertebral levels T12 and L4, prior to and immediately after the effort and then at 1, 5 and 10 min following a 60 s MVC. A small decrease in maximum torque was observed during 60 s MVC, followed by a non significant step-wise increase. The highest torque value was recorded 10 min post MVC. There was a trend for the ratios of left:right EMG RMS amplitudes to be higher following the fatigue in the lower back and to decrease in the upper back, suggesting the task involved differential use of left and right sides in addition to upper and lower back muscles. This study suggests that 60 s MVC induces differential activation of left and right sides and upper and lower parts of the trunk extensors. The apparent potentiation in force and asymmetry of activation following the 60 s MVC task requires further investigation.