BackgroundChronic respiratory diseases are associated with cognitive dysfunction, but whether dyspnea by itself negatively impacts on cognition has not been demonstrated. Cortical networks engaged in subjects experiencing dyspnea are also activated during other tasks that require cognitive input and may provoke a negative impact through interference with each other.MethodsThis crossover randomised trial investigated whether experimentally-induced dyspnea would negatively impact on locomotion and cognitive function among 40 healthy adults. Crossover conditions were unloaded breathing or loaded breathing using an inspiratory threshold load. To evaluate locomotion, participants were assessed by the Timed Up and Go test. Cognitive function was assessed by categorical and phonemic verbal fluency tests, the Trail Making Test A and B (executive function), the CODE test from the WAIS-IV (processing speed), and by direct and indirect digit span (working memory).ResultsThe mean time difference to perform the Timed Up and Go test between unloaded and loaded breathing was −0.752 s (−1.012 to −0.492; p<0.001). Executive function, processing speed and working memory performed better during unloaded breathing, particularly for subjects starting first with the loaded breathing condition.ConclusionOur data suggest that respiratory threshold loading to elicit dyspnea had a major impact on locomotion and cognitive function in healthy adults.