Effects of dual task difficulty in motor and cognitive performance: Differences between adults and adolescents

•Dual-task did not produce a postural control disturbance in young adults.•Dual-task cost in adolescents was high during easy postural tasks.•In unipedal stance position dual-task did not affect postural control in adolescents.

In the present study our aim was to compare dual-task performance in thirteen adolescents and fifteen young adults while concurrently performing a cognitive and a motor task. The postural control variables were obtained under three different conditions: i) bipedal stance, ii) tandem stance and iii) unipedal stance. The cognitive task consisted of a backward digit span test in which the participants were asked to memorize a sequence of numbers and then repeat the number in reverse order at three different difficulty levels (i.e. with 3, 4 and 5 digits). The difficulty of the cognitive task was seen to have different effects on adolescents and young adults. Adolescents seem to prioritize postural control during high difficulty postural conditions while a cross-domain competition model appeared in easy postural conditions.