Compared to a stationary control condition, results confirmed significant dual-task interference effects during both walking conditions, and this effect was more pronounced during overground walking, suggesting that overground walking imposes greater demands and increases competition between cognitive and motor processes for shared cognitive resources.
Key Findings
Results
Dual-task interference effects were present during both treadmill and outdoor overground walking relative to a seated control condition in healthy older adults.
Thirty-six older adults performed an auditory Go/No-Go task while seated, walking on an indoor treadmill, and walking outdoors overground.
Cognitive task performance was assessed behaviourally, alongside mobile EEG and wearable motion-tracking sensors.
The abstract states that results 'confirmed significant dual-task interference effects during both walking conditions' compared to the stationary control.
Results
The dual-task interference effect was more pronounced during overground walking than during treadmill walking.
The comparison was between outdoor overground walking and indoor treadmill walking, each combined with the auditory Go/No-Go task.
The abstract reports that the interference effect 'was more pronounced during overground walking.'
The specific effect sizes and statistics are not given in the abstract.
Discussion
The authors interpret the greater interference during overground walking as reflecting higher demands that increase competition between cognitive and motor processes for shared cognitive resources.
This interpretation is based on the stronger dual-task effects found overground versus treadmill.
The authors frame it in the context of reduced motor automaticity in healthy aging, which may increase top-down control and susceptibility to cognitive-motor interference and fall risk.
Conclusions
Studying natural, real-world walking conditions helps reveal the cognitive demands of locomotion that may not be captured on a treadmill.
The study was designed to explore real-world demands by comparing outdoor overground and indoor treadmill walking.
It used mobile EEG and wearable sensors to enable measurement outside the laboratory.
What This Means
This study asked whether walking on a treadmill indoors places the same mental demands on older adults as walking outdoors on the ground. Thirty-six healthy older adults did a simple listening task (responding to some sounds and withholding responses to others) while sitting, while walking on a treadmill, and while walking outside. Researchers measured how well they did the task and also recorded brain activity and body movement with wearable sensors.
Walking while doing the task made performance worse compared to sitting, both on the treadmill and outdoors. However, this cost was larger during outdoor overground walking. The authors suggest that walking in natural conditions demands more from the shared mental resources used for both thinking and movement, so the two activities compete more.
This research suggests that treadmill-based lab tests may underestimate the mental demands of real-world walking in older adults. That could matter for understanding fall risk and for designing studies of walking and thinking. The abstract does not give detailed numbers, so the size of the differences cannot be judged from it.
Papin L, Welzel J, Koschate-Storm J, Zieschang T, Witt K, Debener S. (2026). Treadmill or Overground? Cognitive-Motor Interference Effects in Healthy Older Individuals.. The European journal of neuroscience. https://doi.org/10.1111/ejn.70724