The Efficacy of Auditory and Haptic Cues Delivered via a Wearable Device to Guide Walking Intensity

Walking is one of the most common forms of physical activity in the UK, promoted by the National Health Service (NHS) through guidelines recommending moderate-intensity exercise. However, the subjective interpretation of "moderate" intensity can lead to inconsistent adherence. Cadence-based thresholds, such as at least 100 steps per minute, have been proposed as an objective alternative, but these absolute markers may not reflect individual fitness levels. Wearable technologies offer an opportunity to personalise physical activity intensity using physiological markers like percentage heart rate reserve (%HRR), and to guide behaviour using nudge-based approaches such as cadence cueing. This study investigated whether metronome (auditory) and haptic cadence cues delivered via an Apple Watch app could guide users to criterion moderate-intensity walking (40 - 59% HRR). Seventy-four adults (18–65 years) completed three 10-minute overground walking trials on a ~60 m figure-of-eight track: (1) self-paced walking guided by NHS moderate-intensity guidelines, (2) walking to an auditory cadence cue, and (3) walking to a haptic cadence cue. Cadence and %HRR were recorded in each condition. Bayesian posterior distributions showed the following mean %HRR (95% credible intervals): self-paced = 41% (39–44%), auditory = 45% (42–47%), and haptic = 43% (41–45%). The proportion of participants reaching 40 - 59% HRR was highest in the auditory (76%) and haptic (65%) cueing conditions, compared to self-paced (41%). These findings suggest wearable-guided cadence cueing, particularly auditory cues, more effectively supports individuals in achieving moderate-intensity walking compared to current NHS guidelines.