Effects of summary knowledge of results in motor skills acquisition

The effects of Summary Knowledge of Results (KR) were tested, using 30 volunteers and a positioning task in which a tennis ball had to be transported in 30 trials, following a specific sequence and with a target time of 3000 msec. Ten minutes after the acquisition phase, the transfer test was performed with 10 trials of different sequences and target times. The retention test took place 24 hours later with 10 trials of the same sequence and target time as the acquisition phase. In the transfer and retention tests, KR was not provided. The volunteers were randomly divided into three groups: G5 (KR every five trials); G3 (KR every three trials) and G100 (KR every trial). The results showed that G3 had a smaller absolute error than G100. However, G3 and G5 had a smaller constant error than G100. In general, the effects of G3 and G5 on motor skill acquisition could be caused by the lower KR frequency, which was 33% and 20% respectively.