Acute Impact of FES-Assisted Cycling on Cerebrovascular and Cognitive Function in Healthy Young Adults

It is well-established that functional electrical stimulation (FES) can enhance physical function, but little is known regarding its acute impact on cerebral blood perfusion and its possible acute repercussions on cognition in comparison to a conventional cycling exercise. Thirteen young healthy participants (1 female, 12 males) underwent two testing sessions (25 min of FES-assisted cycling and cycling control) applied in a randomized order and separated by at least 1 week of recovery. Cerebral blood velocity (CBFv) in the middle (right MCAv) and posterior cerebral arteries (left PCAv), cerebrovascular conductance (CVCi) and resistance index (CVRi), cerebral oxygenation (O₂Hb), cardiac output (CO), mean arterial pressure (MAP), and heart rate (HR) were measured continuously throughout the sessions. Cognitive tests (Stroop, RAVLT, and Trail Making Test) were performed before and after each experimental condition to assess the acute effect of FES and cycling on inhibitory control, attention, short-term memory, and mental flexibility. MCAv, PCAv, CO, MAP, HR, and O₂Hb increased similarly throughout both sessions (p < 0.001). An interaction between condition and time (p = 0.034) was observed, indicating that FES-assisted cycling induced greater improvements on the congruent Stroop task. A condition effect (p = 0.023) reported that the RAVLT-A performance was enhanced in control cycling. In conclusion, the present findings reveal that cerebral blood perfusion increases during exercise irrespective of its modalities. Thus, FES-assisted cycling could be explored as a potential strategy to enhance cerebrovascular perfusion, particularly in individuals with marked physical limitations who are unable to engage in voluntary exercise.