DUAL-TASKING WITH SMARTPHONES: AN INVESTIGATION OF THE IMPACT OF VERBAL TEXTING ON GAIT PERFORMANCE IN HEALTHY ADULTS

Purpose The main purpose of this study was to determine how different types of smartphone use impact gait quality in a healthy adult population. While talking on the phone and manual texting have been explored in previous studies, this study fills a gap in the evidence concerning how verbal texting impacts measures of gait quality as compared to other modes of smartphone use. Additionally, the study provides evidence in a healthy population for comparison in future studies of a similar nature with clinical populations. Methods Ten healthy adult participants took part in the study, completing two study visits each. Activity level was collected for each participant using activPAL activity monitors over a five day period, and average time spent upright and stepping was recorded for each individual. During each participant’s second study visit, sensory threshold was tested using a vibratory sensory analyser (VSA-3000), and executive function was evaluated using the Trail-making Test (TMT). A series of walking tasks was then completed, including baseline walking, manual texting while walking (MTW), verbal texting while walking (VTW), and talking on the phone while walking (TPW). Each of these walking tasks was completed in both a quiet (closed) and busy (open) environment. Measures of gait quality were collected during each of these tasks using wi-GAT (Wireless Gait Analysis Tool) sensors, and all data was subsequently analysed using SPSS. Summary of Main Results Analysis revealed that baseline walking significantly differed from all dual-task walking conditions (MTW, VTW, and TPW) in measures of stride length, cadence, and walking speed, but not in double-stance duration. Results were somewhat inconsistent, but generally suggest that all types of smartphone use are somewhat detrimental to gait quality when compared to baseline. Dual-task effect did not differ significantly between walking condition types. Word count of text messages sent was significantly greater for the VTW condition as compared to the MTW condition. Errors made in texting/talking did not significantly differ between MTW and VTW conditions, but were significantly different between MTW and TPW conditions in an open environment. There were significantly more errors made in the VTW condition than in the TPW condition in both open and closed environments. Secondary outcomes (sensory threshold, activity level, executive function) showed no consistent significant correlations with dual-task effect of the MTW, VTW, and TPW conditions. Conclusions The results of this study suggest that all types of dual-tasking with smartphones has some impact on gait quality, and that verbal texting significantly impacts gait quality similarly to previously studied modes of smartphone use (manual texting, talking on the phone). These results will be useful in comparison with clinical populations in the future, and help to fill a gap in the literature concerning how verbal texting impacts gait quality. Future study into the impact of verbal texting on gait quality is warranted, and should aim to further explore the impact of smartphone use on real-world outcomes such as falls risk