Isokinetics and Exercise Science - Volume 12, issue 3

Authors: Kotzamanidis, Christos

Article Type: Research Article

Abstract: The purpose of this study was to examine if a fatigue task of agonist muscles also causes fatigue to the antagonist muscles. Fourteen (n = 14) healthy males (age: 24.3 ± 2.5 y) participated in two isokinetic fatigue protocols (IFPs) at the angular velocity of 60°/s. The motion ranged from 0° to 90° of knee flexion. The first protocol consisted of 25 concentric maximal trials. The second protocol consisted of 60 concentric …submaximal trials with a resistance equal to 60% of the maximum isokinetic torque exerted at 60°s^{-1} . The muscles selected for EMG recording were Vastus Medialis (VM) and Vastus Lateralis (VL) as agonists and Biceps Femoris (BF) as antagonist. Both protocols were performed with isolated extensions. However, reciprocal maximal knee extension-flexion trials were performed periodically for the estimation of torque and EMG activity of BF muscle. The obtained results indicate that both protocols cause a significant decrease of torque and EMG activity of the agonist muscles. On the contrary, they did not affect the torque and EMG activity of the antagonist muscle. Thus, it can be assumed that antagonist muscles are not fatigued during a fatigue task and they are regulated mainly by central neuronal mechanisms. Show more

Keywords: fatigue, isokinetic, agonist muscles, antagonist muscles

DOI: 10.3233/IES-2004-0168

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 167-171, 2004

Authors: Cardone, C. | Menegassi, Z. | Emygdio, R.

Article Type: Research Article

Abstract: The purpose of this prospective study was to monitor the development of muscular strength and find possible deficits in following reconstruction of the anterior cruciate ligament and rehabilitated by means of the accelerated protocol. Isokinetic assessments of 67 patients were conducted at 2, 4 and 6 months postoperatively. A significant increase (30%) in knee extension strength was found in the operated knee between 2 and 6 months leaving a deficit of 25% relative to the healthy …knee without clinical evidence of instability. Knee flexion strength did not vary during the treatment. We conclude that knee extension strength constitutes a reasonable developmental parameter during accelerated ACL reconstruction rehabilitation. Show more

Keywords: isokinetic assessment, anterior cruciate ligament, rehabilitation

DOI: 10.3233/IES-2004-0169

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 173-177, 2004

Authors: Horvat, Michael | Ray, Christopher | Croce, Ron | Blasch, Bruce

Article Type: Research Article

Abstract: The purpose of this investigation was to compare the isokinetic strength characteristics of visually impaired with sighted individuals. Thirty age-matched participants who met the criteria for blind and partially sighted were matched according to age, height, and sex. Participants were evaluated on a Cybex Isokinetic dynamometer at speeds of 90 and 180 deg/sec. The main outcome measures were peak torque normalized by body weight; and power adjusted by body weight. Data was analyzed by using separate …2 × 2 × 2 × 2 (group × gender × muscle × velocity) repeated measures analyses of variance (ANOVAs). Separate ANOVAs were performed because of the relatively low number of subjects used in the investigation. Results demonstrated significant group, velocity and muscle main effects; sighted individuals had significantly greater values for peak torque and power than individuals with visual impairments. In conclusion, it appears that individuals with visual impairments are deficient in strength and power compared to sighted individuals. Interventions programs should begin early in an individual's development and stress developing muscular strength and power. Show more

Keywords: visual impairment, strength, power, and work

DOI: 10.3233/IES-2004-0171

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 179-183, 2004

Authors: Mahieu, N.N. | Witvrouw, E. | Stevens, V. | Willems, T. | Vanderstraeten, G. | Cambier, D.

Article Type: Research Article

Abstract: The purpose of this study was to examine the test-retest reliability for the real time ultrasonic measurement method that is used to determine the stiffness of the Achilles tendon. Twenty-one healthy men and women aged 20–50 years took part in the study. The subjects underwent three identical test sessions held seven days apart. The lengthening of the tendon during maximal isometric plantar flexion was determined using ultrasonography. A dynamometer was used to measure torque output during …isometric plantar flexion. The relationship between the muscle force and the elongation of the tendon was calculated to become a measure of the stiffness of the Achilles tendon. The ICC for the stiffness of the right and the left Achilles tendon was 0.80 and 0.82 respectively, indicating a good reliability. The results demonstrate that this technique is reliable for the evaluation of the elastic properties of the Achilles tendon. This may be clinically important in the assessment of tendon properties. Show more

Keywords: stiffness, tendon, ultrasonography, reliability

DOI: 10.3233/IES-2004-0172

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 185-191, 2004

Authors: Kablan, Nilüfer | Ertan, Hayri | Ünver, Fatma | Kirazci, Sadettin | Korkusuz, Feza

Article Type: Research Article

Abstract: Proprioceptive sense plays an important role in shoulder joint movements and stability especially in executing performance like playing voleyball. The aim of this study was to evaluate the effect of different positions, the rotator cuff muscle fatigue and experience on shoulder proprioceptive sense among male volleyball players. Twenty elite and 20 beginner volleyball players participated in this cross-sectional study. Shoulder proprioceptive sense was determined by measuring participant's perception of joint position with …the joint at 90° abduction, external rotation and 90° abduction, neutral rotation. Participants were tested at 2°/s before and after exercising on an isokinetic-testing machine until fatigued with dominant extremities were assessed. The results revealed significant difference between proprioceptive senses of beginner volleyball players at 10–20° and 15–20° in external rotation before fatigue. The proprioceptive sense of elite volleyball players before and after fatigue was statistically different at 20°, whereas for the beginner players significance was indicated at 10 and 15°. However, no significant difference was found between elite and beginners in the proprioceptive scores at the 3 angles in both directions before and after the fatigue test. It was concluded that the effect of fatigue on proprioceptive sense is related to experience, but experience itself had no effect on proprioceptive sense. Show more

Keywords: proprioceptive sense, shoulder joint

DOI: 10.3233/IES-2004-0173

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 193-198, 2004

Authors: Egret, Claire | Weber, Jacques | Dujardin, Franck | Chollet, Didier

Article Type: Research Article

Abstract: Background: EMG equipment is used to measure muscular activity during sports movements. A methodological study is hence necessary to identify how this cumbersome equipment may hinder golfers in performing the golf swing. Methods: Measurements of kinematic data during swing were conducted using an optoelectronic system. Surface bipolar electrodes with integrated preamplifiers were used to monitor the myoelectric signals during golf swing. Six experienced right-handed male golfers performed six swings with electromyographic …equipment fixed on their body and six swings without electromyographic equipment. Results: There was a significant effect in terms of shoulder joint rotation at maximal backswing (7.7%), in the right elbow flexion at the address (3.7%), at the top of the backswing (3.1%) and in the clubhead speed (6.7%). Conclusions: EMG equipment influences the kinematic pattern of the golf swing. Show more

Keywords: golf swing, EMG equipment, kinematics, reproductibility

DOI: 10.3233/IES-2004-0174

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 199-202, 2004

Authors: Maquet, D. | Forthomme, B. | Demoulin, C. | Jidovtseff, B. | Crielaard, J.M. | Croisier, J.L.

Article Type: Research Article

Abstract: Objective. To establish the inter-session reproducibility of isokinetic concentric strength and fatigue profile of the elbow flexors and extensors in sedentary women. Methods. Forty healthy women who were physically inactive or engaged in recreational sports were included in the study. Strength was evaluated at 60 and 180°/s. The fatigue protocol consisted of 30 maximal-intensity elbow flexion and extension at 180°/s. Results. The extensors were stronger than flexors while no dominance effect was …apparent. In addition the work output of the extensors during the fatigue protocol was larger than the flexors', the previous being more fatigue resistant. A dominance effect was observed for the extensors in the fatiguing protocol. Reproducibility expressed by the coefficient of variation was less or equal to 11%. Conclusions. This study highlights satisfactory reproducibility of isokinetic strength and fatigue parameters. The values derived may be useful for interpretation of clinical tests or characterization of pathological states in women with similar characteristics. Show more

Keywords: elbow, isokinetic strength, fatigue, reproducibility

DOI: 10.3233/IES-2004-0175

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 203-208, 2004

Authors: Biette, Nicolas | Tourny-Chollet, Claire | Beuret-Blanquart, Françoise

Article Type: Research Article

Abstract: The purpose of this study was to compare the effects of two different types of resistance training in sedentary women. Twenty students were assigned to three groups: concentric training (CT), combined concentric and isometric training (ICT) and control (CN). The training protocol consisted of 8 weeks × 3 days. The results demonstrated improvements in both groups. However, greater isometric strength gains were achieved among ICT subjects but no difference regarding the concentric mode. The results …indicate that quadriceps muscle strength may be greatly improved by combined training as compared to concentric training alone. Show more

Keywords: strength, knee extensors, training, isometric/concentric, women

DOI: 10.3233/IES-2004-0176

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 209-213, 2004

Authors: Codine, Ph. | Dellemme, Y. | Denis-Laroque, F. | Herisson, Ch.

Article Type: Research Article

Abstract: Recovery of full knee extension after total knee replacement (TKR) is necessary in order to obtain a good quality in walking. One of the means for accomplishing a successful rehabilitation of this operation is by using eccentric exercises of the hamstrings for increasing tendon- muscular extensibility. The findings regarding knee extension of 30 TKR patients who exercised this muscle group 15 min/day, 5 days/week from day10 to day30 following surgery were compared with a reference group …of 30 TKR patients who did not train similarly. The experimental group achieved a significantly better extension but no differences were noted vis-a-vis RoM in flexion and quadriceps and hamstrings strength. Training was well tolerated without inflammatory reaction or hamstrings muscle pain. Therefore this technique may be prescribed for faster recovery of knee extension following TKR. Show more

Keywords: isokinetic, eccentric, hamstrings, total knee arthroplasty, rehabilitation

DOI: 10.3233/IES-2004-0177

Citation: Isokinetics and Exercise Science, vol. 12, no. 3, pp. 215-218, 2004