Isokinetics and Exercise Science - Volume 20, issue 1

Authors: Bohannon, Richard W. | Dvir, Zeevi

Article Type: Research Article

Abstract: The strength profile of two patients suffering from polymyositis is presented. In the first patient, 6 muscle actions (shoulder abduction, elbow flexion, grip, hip flexion, knee extension, ankle dorsiflexion) were measured bilaterally in 3 ways including a modification of the Stroke Impact Scale, manual muscle testing and hand-held dynamometry. All methods indicated considerable weakness, including that of the distal muscles. In the second patient, concentric and eccentric strength of the quadriceps was measured 6 …times over a period of 13 years. The findings strongly demonstrated a progressive increase in knee extension weakness. The results support the notion that polymyositis affects distal as well as proximal muscles and that the weakness is fully appreciated when the strength of the muscles involved is quantitatively measured using dynamometry. Show more

Keywords: Polymyositis, dynamometry, case study

DOI: 10.3233/IES-2011-0432

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 1-4, 2012

Authors: Beck, Travis W. | Stock, Matt S. | DeFreitas, Jason M.

Article Type: Research Article

Abstract: The purpose of this investigation was to use electromyography (EMG) combined with pattern classification procedures to examine differences in activation among the superficial quadriceps femoris muscles during fatiguing concentric isokinetic muscle actions. Ten men (mean ± SD age=22.4 ± 1.2 yrs) and six women (mean ± SD age=23.0 ± 2.1 yrs) performed 50 consecutive maximal concentric isokinetic muscle actions of the dominant leg extensors at a velocity of …180°/s. During each muscle action, bipolar surface EMG signals were detected from the vastus lateralis (VL), rectus femoris (RF), and vastus medialis (VM). These signals were then processed with a wavelet analysis, and the resulting intensity patterns were classified using pattern classification procedures. The results demonstrated that the EMG intensity patterns could be separated into muscle-specific groups with rates ranging from 89–100% and classified with accuracy levels between 84% and 100%. These findings showed muscle-specific activation patterns in the quadriceps femoris muscles, despite common femoral nerve innervation. These differences in activation likely reflected the different roles of each muscle during leg extension. Future studies need to be done to further examine these differences during other activities that include movement at the hip joint, such as running and cycling. Show more

Keywords: Electromyography, wavelet, pattern classification

DOI: 10.3233/IES-2011-0433

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 5-12, 2012

Authors: Stradijot, Fulvio | Pittorru, Gian Mario | Pinna, Marco

Article Type: Research Article

Abstract: Introduction: This project proposes the inclusion of functional assessment as an essential branch of a training program applied to a group of young elite judo and wrestling athletes to investigate for possible asymmetries of lower limbs, a potential cause for future injuries. Methods: A group of young male elite Sardinian judo and wrestling athletes was randomly selected and were functionally evaluated with three different tests. Strength and balance abilities were measured while muscle power was assessed by measuring …jump height, flight time and maximum contraction speed. Subjects were compared according to their right and left leg performance. Results: Generally, no significant bilateral difference were indicated for any of the applied tests, between right and left legs in all considered parameters concerning the three utilized tests, with the exception of peak torque values of the knee extensors. Conclusion: This study indicates that judokas are distinguished by general bilateral symmetry in certain functions. This should serve as an important guideline for both clinicians and coaches. Show more

Keywords: Functional assessment, injury prevention, training program, asymmetry, judo, wrestling

DOI: 10.3233/IES-2011-0434

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 13-16, 2012

Authors: Mota, Nuno | Ribeiro, Fernando

Article Type: Research Article

Abstract: This study aimed to investigate the association between shoulder proprioception and shoulder rotators strength in water polo players. Twenty male water polo players aged 20.2 ± 2.3y participated in the study. Shoulder proprioception was evaluated by assessing joint position sense (JPS) at 30° of external rotation and at 30° of internal rotation. Shoulder external and internal rotators concentric and eccentric muscle strength was evaluated isokinetically at 120°/s. JPS acuity at …30° of external rotation [4.7 (3.5°)] was similar to that observed at 30° of internal rotation [4.0 (5.3°)]. The external/internal rotators strength ratio were 0.67 (0.23) and 0.66 (0.18), respectively for concentric and eccentric efforts while the dynamic control ratio was 0.69 [0.16]. Negative and significant correlations were found between relative error at 30° of external rotation and concentric and eccentric external rotators PT: r = −0.445 and r = −0.483, respectively, and the eccentric strength ratio of the external to internal rotators (r =−0.505). In addition the dynamic control ratio was lower than the recommended values for overhead athletes, which may expose/predispose the players to shoulder injury. Show more

Keywords: External rotators, functional ratio, internal rotators, joint position sense

DOI: 10.3233/IES-2011-0435

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 17-21, 2012

Authors: Caruso, John F. | Daily, Jeremy S. | Olson, Nathan M. | McLagan, Jessica R. | Taylor, Skyler T. | Mason, Melissa L. | Davidson, Mark E. | Borgsmiller, Jake A. | Riner, Rebekah D.

Article Type: Research Article

Abstract: Healthy college-age subjects (43 men, 32 women) provided data to examine the effect of arm swing on the attainment of maximum countermovement vertical jump heights. Subject's data were collected from two laboratory visits. Maximum-effort jumps were performed, both with and without an arm swing at each visit, as peak height values were collected and recorded by an instrumented platform. A 2 (gender) x 2 (jump condition) ANOVA revealed an interaction, as jumps done with an arm …swing done by men produced the highest maximum jump heights. Using two separate multivariate regression analyses, four anthropometric variables (height, body mass, upper leg length, lower leg length) explained a significant amount of variance in maximum height values for jumps done with and without an arm swing. Finally multivariate regression also revealed two upper extremity anthropometric measures (upper and lower arm lengths) accounted for a small (R^{2} = 15% yet significant amount of variance in delta (jumps done with – without an arm swing) height values. Continued research should examine additional predictor variables in an attempt to explain more of the variance in jump height values. Show more

Keywords: Countermovement, anthropometry, gender

DOI: 10.3233/IES-2011-0436

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 23-29, 2012

Authors: Dirnberger, Johannes | Kösters, Alexander | Müller, Erich

Article Type: Research Article

Abstract: The purpose of this study was to determine relative as well as absolute reproducibility for the IsoMed 2000-dynamometer in measuring Peak Torque (PT) during concentric and eccentric maximum knee extension at two angular velocities. Thirty five physically active male subjects (mean age: 23.7 years) with no prior experience of isokinetic exercise were measured on three occasions (T1–T3), separated by 48–72 h. Detection of systematic errors was performed using repeated measures analysis of variance (ANOVA) with Bonferroni …post hoc adjustments. Further statistical calculations were done between consecutive pairs of sessions (T1–T2; T2–T3). Intraclass correlation coefficients (ICC 2,1) were calculated to assess relative reproducibility, whereas absolute reproducibility was determined by the standard error of measurement (SEM). A highly significant systematic error was found for the eccentric measurements with values on the first visit being around 5% lower than corresponding values on the second and third visit. ICC values of 0.907–0.955 and 0.968–0.984 with corresponding values of SEM of 7.4–19.1 and 4.5–10.9 Nm were found for T1–T2 and T2–T3, respectively. In conclusion, high reproducibility was shown for the IsoMed 2000-dynamometer in measuring PT during concentric and eccentric knee extension. However, due to a systematic practice-based improvement found for eccentric measurements, we suggest to do a familiarisation session prior the actual testing sessions in practice. Show more

Keywords: Reproducibility, practice-based improvement, maximum strength testing, knee extension, IsoMed 2000

DOI: 10.3233/IES-2012-0437

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 31-35, 2012

Authors: Tasmektepligil, M. Yalcin | Ozkaya, Ozgur | Kabadayi, Menderes | Kuzucu, O. Erinc

Article Type: Research Article

Abstract: The elliptical Wingate test (EWT) is a new exercise modality that enables whole body activation during tests, while the cycle Wingate test (CWT) is a traditionally used method for anaerobic performance. The purpose of this study was to analyze total peak blood lactate, plasma volume change in lactate and heart rate responses as well as peak power, average power, minimum power, power drop and fatigue index ratio on this new exercise modality and to compare the …obtained results with those derived from the CWT. Based on a sample of 20 healthy subjects all of the above parameters were significantly greater for the EWT than for CWT (p0.000). Consequently the EWT is associated with greater physiological responses and anaerobic outcomes compared to the CWT. Show more

Keywords: Elliptical Wingate anaerobic test, cycle ergometer, lactate, heart rate

DOI: 10.3233/IES-2012-0438

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 37-39, 2012

Authors: Ruivo, R. | Pezarat-Correia, P. | Carita, A.I.

Article Type: Research Article

Abstract: In this case control study we aimed at characterizing elbow and shoulder muscular strength profile in male judokas. Isokinetic variables pertaining to shoulder internal and external rotation and elbow flexion and extension were measured at 60 and 180°/s, in a group of 22 national male judokas and in a control group of 22 healthy participants. The judo athletes were significantly stronger than the non-athletes. The mean values of ER:IR ratio observed in the judokas group were …lower than in the control group. The mean values of elbow Flex:Ext ratio were similar in both groups at 60°/s, but significantly higher at 180°/s in the judokas group. These findings indicate sport specific muscular adaptations in the dominant shoulder and elbow in male judo athletes. The results of this study provide information that may be of importance for developing training and rehabilitation programs for judo athletes. Show more

Keywords: Judo, isokinetics, shoulder, elbow, muscle strength

DOI: 10.3233/IES-2012-0439

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 41-45, 2012

Authors: Yaman, Meltem | Colakoglu, Muzaffer | Turgay, Faruk | Ozkol, Zeki | Akşit, Tolga | Ozkaya, Ozgur | Yapicioglu, Bulent

Article Type: Research Article

Abstract: The purpose of this study was to estimate the effects of ribose supplementation on interval anaerobic performance and fatiguing substance concentrations. The study cohort consisted of physically active, young male volunteers (n=15). With a double-blind cross over study design, each participant completed two all-out anaerobic exercise sessions, one week apart, one by supplementing maltodextrine and the other by supplementing ribose (150 mg/kg in each test). Two repetitions of 30-s maximal performance with a 4-min …interval were completed. Blood samples were taken at rest and five minutes after the second sprint repetition. Neither the biochemical parameters: pH (−0.32 ± 0.09 vs. −0.26 ± 0.11), lactate (La) (13.8 ± 1.9 vs. 13.3 ± 2.7 mM, ammonia (423 ± 190 vs. 404 ± 166 μ mol/L), inorganic phosphate (Pi) (0.68 ± 0.53 vs. 0.72 ± 0.63 mM) nor the anaerobic output (746.2 ± 82.5 vs. 760.2 ± 86.8 watts) were affected by placebo and ribose supplementations significantly (p> 0.05). In conclusion, based on this protocol, anaerobic performance and/or biochemical status are not affected by ribose supplementation. Show more

Keywords: Ribose, anaerobic performance, inorganic phosphate, ammonia, pH, lactate

DOI: 10.3233/IES-2012-0440

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 47-50, 2012

Authors: Caruso, John F. | Coday, Michael A. | Davidson, Mark E. | Riner, Rebekah D. | Borgsmiller, Jake A. | Olson, Nathan M. | Taylor, Skyler T. | McLagan, Jessica R.

Article Type: Research Article

Abstract: To assess the subsequent testosterone/cortisol ratio (TCr) from flywheel-based resistive exercise, using a within-subjects design volunteers (7 men, 10 women) performed three seated leg press workouts on an ergometer (YoYo Technologies, Stockholm Sweden). Comprised of ten-repetition sets, the workouts entailed: a three-set protocol composed of concentric and eccentric actions (CE3), as well as concentric-only paradigms of three (CO3) and six (CO6) sets. Venous blood, collected before bouts and at one and 30 minutes post-exercise, …was used to quantify the TCr. Data were examined with ANOVA and multivariate regression. ANOVA yielded a gender x time TCr interaction, as male values declined significantly yet women's data were unchanged. With the TCr at one and 30 minutes post-exercise as separate criterion measures, and data pooled across genders and workouts, multivariate regression revealed significance per dependent variable. Univariate correlations showed the best predictors of the post-exercise TCr in descending order were: body mass, average power and delta lactate. Gender and quadriceps muscle volume may have acted as confounding variables to allow body mass to the best current study predictor. Continued research should examine additional predictor variables, as current results only accounted for roughly 30% of the total criterion measure variance. Show more

Keywords: Body mass, average power, delta lactate

DOI: 10.3233/IES-2012-0441

Citation: Isokinetics and Exercise Science, vol. 20, no. 1, pp. 51-60, 2012