The effects of secondary motor and cognitive tasks on gait depend on functional walking ability in non-traumatic neurological patients: a feasibility pilot study

Adaptive locomotion requires the integration of cognitive and motor processes and is challenged in neurological disorders. Dual-task (DT) training may improve cognitive–motor coordination, but its feasibility across heterogeneous clinical populations is uncertain. This pilot study aimed to understand if the effects of a secondary motor or cognitive task added to a walking task depend on the functional walking abilities of the subjects. We enrolled 30 participants with neurological disorders not related to traumatic events, 5 for each one of the following groups: healthy young subjects (HeY), healthy control subjects (HeC), subjects with stroke (ictus, IC), Parkinson’s disease (PD), multiple sclerosis (MS), and Long-COVID sequelae (LC). Spatiotemporal gait parameters were recorded using a wearable inertial magnetic unit, and subjective workload was assessed with the visual analog scale (VAS) and NASA-Task Load Index. Regression models revealed strong baseline–DT coupling for stride duration (slopes 1.11–1.37; R2 0.85–0.97), stride length (slopes 0.93–0.94; R2 0.86–0.93), walking speed (slopes 0.87–0.98; R2 0.78–0.93), and gait ratio (stance/swing, slopes 0.38–0.60; R2 0.21–0.52). Mixed-effects analyses identified significant group effects for walking speed (F(5) = 7.218, p < 0.001), stride length (F(5) = 4.834, p = 0.001), gait cycle duration (F(5) = 5.630–5.664, p < 0.001), Walking Quality (F(5) = 4.340–4.373, p = 0.001), and propulsion index (F(5) = 5.668–6.843, p < 0.001). The incongruent DT condition was the most sensitive in differentiating clinical groups. NASA-TLX indicated higher perceived workload in IC and MS compared with non-clinical groups. The protocol was completed by all participants without adverse events, supporting the feasibility of the procedure in this pilot sample. Its predictable scaling across baseline gait metrics supports its use as a personalized rehabilitation tool for diverse neurological populations. (ClinicalTrials.gov NCT07254377).