Cognitive–motor interference: Effects of smartphone use on static balance and mobility

This study examined how smartphone-related cognitive load interferes with motor control during static balance and mobility tasks. Excessive smartphone use has been associated with attentional shifts and divided cognitive resources, potentially impairing postural control and gait stability. Therefore, we aimed to investigate the effects of smartphone use on static balance and mobility performance under dual-task conditions and to explore whether the frequency of smartphone use while walking moderates this relationship. Sixty participants were included in the study. The participants' daily smartphone usage time and frequency of smartphone use while walking were assessed. Mobility was measured using the Timed Up and Go (TUG) test, while static balance ability was evaluated using a digital balance board. To determine the effects of dual-tasking, participants repeated the TUG and static balance tests while performing motor and cognitive tasks on a smartphone. While participants were using smartphones, TUG-motor, TUG-cognitive, and static-motor balance performances deteriorated (<i>p</i> < 0.001, <i>p</i> < 0.001, <i>p</i> = 0.014, respectively). However, smartphone use did not change static-cognitive balance performance (<i>p</i> = 0.079). In addition, there was no relationship between the daily smartphone use duration and the frequency of smartphone use while walking and the effect of smartphone on balance performance (<i>p</i> > 0.05). Regardless of the frequency of smartphone use while walking, using smartphones in static or dynamic conditions may negatively affect individuals' balance performance, leading to accidents and falls.