Ricardo Demétrio de Souza Petersen

Effect of kinetic redundancy on hand digit control in children with DCD.

We investigated finger strength and the ability to control digit force/torque production in children with developmental coordination disorder (DCD) using manipulative tasks with different kinetic redundancies (KNR). Age-related changes in finger strength and finger force/torque control in typically developing (TD) children were also examined to provide a developmental landscape that allows a comparison with children with DCD. Forty-eight TD children (7-, 9-, and 11- year-olds) and sixteen 9-year-old children with DCD participated in the study. Three isometric tasks with different KNR were tested: constant index finger pressing force production (KNR=0), constant thumb-index finger pinching force production (KNR=1), and constant thumb-index finger torque production (KNR=5). Each subject performed two conditions for each isometric task: maximum voluntary force/torque production and constant force/torque control (40% of maximum force/torque). The results showed that the maximum force/torque production increased and the variability of constant force/torque control decreased with age in all tasks in TD children. Children with DCD showed larger variability than TD children in the constant thumb-index finger pinching torque production. These results suggest that children with DCD, as compared to TD children, are capable of producing the same level of maximum finger force, but have poor control in manipulation tasks with a large number of kinetic redundancies.

Características imunológicas e virológicas e as variáveis flexibilidade (FLEX) e força de resistência abdominal (FRA) de crianças e adolescentes portadores de HIV/AIDS em uso de TARV

INTRODUCAO: No contexto da cronicidade da AIDS, escassos estudos avaliaram variaveis de aptidao fisica em criancas e adolescentes; entretanto, com adultos tem-se registrado a importância da adesao aos exercicios fisicos associados a TARV para melhorar essas variaveis. OBJETIVO: Identificar as caracteristicas imunologicas, virologicas e as variaveis flexibilidade (FLEX) e forca de resistencia abdominal (FRA) de criancas e adolescentes portadores de HIV/AIDS em uso de TARV. METODO: Estudo transversal realizado no Ambulatorio de HIV/AIDS em Pediatria do Hospital de Clinicas de Porto Alegre. A amostra foi obtida consecutivamente por 63 pacientes (dez criancas e 53 adolescentes), de ambos os sexos, entre sete e 17 anos. A analise dos dados foi realizada no SPSS, versao 18.0, (p < 0,05). Para comparar as medias foi utilizado o teste t de Student pareado. RESULTADOS: O tempo medio de diagnostico do HIV e da TARV atual foram 11 ± 3,42 anos e 40 ± 32,78 meses. A forma de transmissao prevalente foi a transmissao vertical (98,42%). A carga viral indetectavel foi identificada em 73,1%. A contagem de T CD4+ e T CD8+, bem como sua relacao, apresentaram as medias de 932,25 ± 445,53 celulas/ml, 1.018 ± 671,23 celulas/ml e 0,90 ± 0,41. Nas variaveis FLEX e FRA, independente do sexo, houve maior proporcao de criancas e adolescentes classificadas abaixo dos pontos de corte. Observou-se diferenca significativa entre a FRA e seus respectivos pontos de corte no periodo de diagnostico do HIV (p = 0,032), T CD4+ (p = 0,008) e na carga viral (p = 0,030). Houve diferenca significativa entre a FLEX e seus respectivos pontos de corte nas variaveis T CD4+/T CD8+ (p = 0,022) e na carga viral (p = 0,040). CONCLUSAO: Os resultados demonstraram que existe uma estabilidade nas caracteristicas imunologicas e virologicas, porem, niveis indesejados de aptidao fisica nas variaveis FLEX e FRA.

Efeito da posição da articulação do cotovelo no controle de torque de supinação do antebraço em jovens adultos

Effects of elbow joint position on forearm supination torque control among young adults Background: Large numbers of cases of pathological conditions in the forearm and elbow that have been reported in the literature are associated with tasks involving effort and repetitive movements of the arms and hands. Elbow position is known to affect the production of maximum forearm supination torque, and is a critical factor in designing appropriate therapeutic exercises. However, to our knowledge, there are no data on the effects of elbow position on tasks requiring control over submaximal torque levels. Objective: This study investigated the effects of elbow position on the production of maximum isometric forearm supination torque, and on constant and continuous torque control at different submaximal torque levels. Method: Sixteen young adults (24.7 ± 2.2 years old) were asked to perform two tasks: production of maximum lateral pinch torque (thumb and index finger) and controlled lateral pinch constant torque. Both tasks were evaluated at four different elbow positions (free position, 0°, 45° and 90° of elbow flexion) and three submaximal levels of lateral pinch torque production (20%, 40% and 60%). Maximal torque, variability, irregularity and accuracy of the motor response were used as dependent variables. Results: Greater torque values were found when the elbow joint was not restricted. The torque control tasks were not affected by the elbow position. However, greater variability and irregularity and lower accuracy in torque response were recorded with progressively increased submaximal torque levels. Conclusion: The results suggest that elbow position is not a determining factor for rehabilitation exercises that include torque control, in relation to forearm supination.