Effect of adding cognitively demanding tasks on soccer skill performance.

The effect of adding cognitively demanding elements to the performance of a real-world motor task in which functional interference among the elements in performance existed was investigated across level of expertise. The primary task involved running as quickly as possible through a 15.25-m slalom course. Two secondary tasks were used, dribbling of a soccer ball and identification of geometric shapes projected on a screen located at the end of the slalom course. 4 novice, 5 intermediate, and 5 expert female soccer players served as subjects and performed three trials each of three experimental conditions: running through the slalom course, running through the slalom course while dribbling a soccer ball, and running through the slalom course while dribbling a soccer ball and identifying geometric shapes. Analysis of variance using a 3 (experimental condition) x 3 (level of expertise) design gave significant main effects and a significant interaction. The latter indicated that, although the addition of cognitively demanding elements caused a decrement in performance, the amount of decrement decreased as level of expertise increased. It was concluded that structural interference between elements of performance decreased the positive effect of automation of one element on dual task performance.