Paulo Gentil, Fabricio Boscolo Del Vecchio, Antonio Paoli, Brad J Schoenfeld and Martim Bottaro
for strength assessment. For example, one may conclude that an intervention is highly efficient when measuring its results by 1RM, while classifying the results of another intervention as disappointing when evaluating it by isokinetic dynamometry. However, this may not be reflective of the protocols, but rather of the tests performed.
Isokinetic dynamometry and 1RM tests are both considered as valid and often interchangeable methods for evaluating changes in muscle strength in nutritional and/or exercise interventions. However, the results of the present study
The aim of the investigation was to: 1) compare shoulder external/internal rotator muscles’ peak torques and average power values and their ratios in the dominant and non-dominant arm; 2) determine correlations between shoulder rotator muscles’ peak torques, average power and ball-throwing speed in handball players. Fourteen 14 to 15- year-old male athletes with injury-free shoulders participated in the study (body height: 176 ± 7 cm, body mass 63 ± 9 kg). The tests were carried out by an isokinetic dynamometer system in the shoulder internal and external rotation movements at angular velocities of 60°/s, 90°/s and 240°/s during concentric contractions. The eccentric external- concentric internal rotator muscle contractions were performed at the velocity of 90°/s. The player threw a ball at maximal speed keeping both feet on the floor. The speed was recorded with reflected light rays. Training in handball does not cause significant side asymmetry in shoulder external/internal rotator muscle peak torques or the average power ratio. Positive correlations between isokinetic characteristics of the shoulder internal and external rotator muscles and ball-throwing speed were determined. The power produced by internal rotator muscles during concentric contractions after eccentric contractions of external rotator muscles was significantly greater in the dominant than in the non-dominant arm. Thus, it may be concluded that the shoulder eccentric external/concentric internal rotator muscle power ratio is significantly greater than this ratio in the concentric contractions of these muscles
Ivan Struhár, Michal Kumstát and Dagmar Moc Králová
different isometric conditions in order to measure the maximum peak torque on the dominant leg of the participant. The low velocity was set at 60 o ·s -1 , and the high velocity at 120 o ·s -1 . Each movement was repeated six times at two velocities, with rest intervals of 60 s between each angular velocity. Verbal encouragement was given throughout testing. The maximum peak torque (PT) was found as the highest value among five contractions for each test condition. Ankle strength was assessed before, 24 and 48 h after the exercise protocol.
Strength imbalances between the hamstrings and quadriceps are an essential predictor for hamstring strain in soccer. The study aimed to investigate and compare the muscle strength imbalances of professional soccer players of different performance levels. One hundred and fifty nine senior male professional soccer players from first (n = 75) and second league (n = 84) Portuguese clubs participated in this study. Muscle strength was evaluated with a REV9000 isokinetic dynamometer. Maximal peak torque data were used to calculate quadriceps and hamstrings strength during concentric and eccentric actions, bilateral asymmetry, conventional strength ratios and dynamic control ratios. Second league athletes produced slightly lower conventional strength ratios in the right and left legs (ES = 0.22, p = 0.17 and ES = 0.36, p = 0.023, respectively) compared to the first league athletes. No significant differences were found in dynamic control ratios or in bilateral asymmetry among first and second league athletes. These findings do not show a clear link between the competitive level and injury risk in soccer players. However, some of the differences found, particularly in conventional strength ratios, highlight the importance of performing off-season and pre-season strength assessments to prescribe and adjust individual strength training programs among professional soccer players.
Baker J, Horton S, Weir P. The masters athlete: understanding the role of exercise in optimizing aging. Routledge, London; New York, p. 204; 2010
Baltzopoulos V, Williams JG, Brodie DA. Sources of error in isokinetic dynamometry: effects of visual feedback on maximum torque. Journal of Orthopaedic and Sports Physical Therapy, 1991; 13: 138-142
Bowers EJ, Morgan DL, Proske U. Damage to the human quadriceps muscle from eccentric exercise and the training effect. Journal of sports sciences, 2004; 22
Susana María Gil, Javier Yanci, Montserrat Otero, Jurgi Olasagasti, Aduna Badiola, Iraia Bidaurrazaga-Letona, Aitor Iturricastillo and Cristina Granados
Wheelchair basketball players are classified in four classes based on the International Wheelchair Basketball Federation (IWBF) system of competition. Thus, the aim of the study was to ascertain if the IWBF classification, the type of injury and the wheelchair experience were related to different performance field-based tests. Thirteen basketball players undertook anthropometric measurements and performance tests (hand dynamometry, 5 m and 20 m sprints, 5 m and 20 m sprints with a ball, a T-test, a Pick-up test, a modified 10 m Yo-Yo intermittent recovery test, a maximal pass and a medicine ball throw). The IWBF class was correlated (p<0.05) to the hand dynamometry (r= 0.84), the maximal pass (r=0.67) and the medicine ball throw (r= 0.67). Whereas the years of dependence on the wheelchair were correlated to the velocity (p<0.01): 5 m (r= −0.80) and 20 m (r= −0.77) and agility tests (r= −0.77, p<0.01). Also, the 20 m sprint with a ball (r= 0.68) and the T-test (r= −0.57) correlated (p<0.05) with the experience in playing wheelchair basketball. Therefore, in this team the correlations of the performance variables differed when they were related to the disability class, the years of dependence on the wheelchair and the experience in playing wheelchair basketball. These results should be taken into account by the technical staff and coaches of the teams when assessing performance of wheelchair basketball players.
Causes for plexus brachialis damage are versatile, and in some cases remain unknown, but mostly result from degenerative and inflammatory processes. Treatment of brachial plexus dysfunction is often conservative and is subject to a team of specialists - neurologists, traumatologists, rehabilitation physicians, kinesitherapists and occupational therapists. The objective of the research is to report the recovery of patients with lesion of plexus brachialis after a complex physiotherapy and rehabilitation treatment program that includes electrostimulation, remedial massage, kinesitherapy, electrotherapy and occupational therapy. A total of 159 patients, treated at the Clinic of Physical Therapy, University Hospital of Pleven, were included in the study. Improvement of measured indexes: pain assessment, centimetry, assessment of upper limb muscle weakness, dynamometry and functional test of activities of daily living, was registered in all patients under observation. In order to achieve good results in the rehabilitation of patients with injured plexus brachialis, timely diagnosis, good medication therapy and early start of complex physiotherapy and rehabilitation are of crucial importance, so that performance of daily living activities improves. The good results come slowly and with difficulties, but the quality of life of patients and the quality of labor performed by them, improves significantly.
Study aim: Increased muscle tone, a common consequence of stroke, has neural and non-neural components. Spasticity is related to the neural component. Non-neural resistance arises from passive stiffness. This study was designed to assess the feasibility of using isokinetic dynamometry to evaluate wrist flexor muscle spasticity in stroke patients.
Materials and methods: Twenty-six patients with hemiplegia in the subacute phase of stroke participated in this study. An isokinetic dynamometer was used to stretch wrist flexor muscles at four velocities of 5, 60, 120 and 180°/s on both the paretic and non-paretic sides. Peak torque at the lowest speed (5°/s) and reflex torque at the three higher speeds were quantified. Peak torque at the lowest speed was attributed to the non-neural component of muscle tone, and was subtracted from the torque response at higher velocities to estimate reflex torque (spasticity). Data from the two sides were compared.
Results: There was no significant difference in peak torque between the paretic (2.47 ± 0.22 N·m) and non-paretic side (2.41 ± 0.28 N·m) at the lowest velocity of 5°/s (p=0.408). However, compared to the non-paretic side, the paretic side showed higher reflex torque (p<0001), and reflex torque increased rapidly with increasing velocity (p < 0.05).
Conclusion: The isokinetic dynamometer distinguished spasticity from the non-neural component and showed higher reflex torque on the paretic side compared to the non-paretic side. This instrument is potentially useful to assess the efficacy of therapeutic interventions aimed at modifying spasticity.