Magnitude e estrutura de variabilidade de desempenho na aquisição de uma habilidade motora de apontamento

Abstract

The aim of the present study was to verify the effects of magnitude and structure of variability in an aiming motor skill acquisition. Twenty two undergraduate volunteers (n=22) performed an aiming task in two phases: acquisition and transfer test. The task presented higher index of difficulty (ID) in transfer test than acquisition phase. Two distinct groups were set according to magnitude of variability standard deviation of movement time (BV and AV), and structure of variability Hurst exponent of movement time (BH and AH) in the last block of trials of acquisition phase. Results showed that BV presented better performance than AV in movement time and worse performance than AV in number correct trials (target was hit). Results still pointed out similar performance of AH and BH in all measures in transfer test. In general, it was possible to conclude that only magnitude of variability influenced negatively performance in transfer test, and even with distinct groups, Hurst exponent was high, showing structured variability in both groups. Then, it was possible to conclude that magnitude and structure of variability present different effects on motor skill acquisition. While magnitude of variability should be reduced through practice, it was not observed low values of structure of variability when performance was better.