Humans process visual information more quickly and accurately when taking a stride than during footfall while walking. Researchers say the finding could lead to improved understanding of changes in mobility as we age and earlier diagnosis of conditions that affect gait.

Most studies of the effects of exercise on cognitive function have examined extended periods of activity, with several showing small improvements in performance (Chang et al, 2012 ). Few, however, have looked at changes within the stride cycle.

A team at the University of Sydney tracked the head and eye movements, and gait, of 45 individuals as they repeatedly walked 10 metres in a straight line. 

Study participants wore virtual reality (VR) headsets and were asked to press a trigger as quickly as possible when elliptical shapes appeared briefly in their field of vision. 

They performed better while swinging their legs from one step to the next than as their feet hit the ground. Their ability to detect the visual stimuli and the speed with which they did so changed in a pattern corresponding to the rhythm of their steps.