Frontiers in Human Neuroscience · Oct 31, 2026
Acute High-Intensity Interval Exercise in Spinal Cord Injury: Psychological Benefits Alongside Cognitive and Neurobiological Responses
By Sara Klinger, Olga Tarassova, Maria M Ekblom et al.
Acute high-intensity interval exercise (HIIE) can lead to improvements in executive functions, but less is known on if, and through what mechanisms, this applies after spinal cord injury (SCI). In this randomized within-subject crossover study, the effects of acute HIIE on working memory, cognitive task-related regional cerebral blood flow, blood biomarkers and psychological responses were investigated. Sixteen adults with chronic SCI (mean age 43.3 ± 10.6 years; 12 men; 9 with paraplegia (T2-T12) and 7 with tetraplegia (C5-C8); > 1-year post-injury) completed a passive rest and a HIIE condition (20 min of double-poling ergometry at 80% of peak power output). Working memory (n-back task) performance was assessed pre- and post- intervention (planned: 10 minutes; actual post-intervention delay: 16.1 ± 4.4 min) with simultaneous measurement of hemodynamics using functional near-infrared spectroscopy (fNIRS) over the prefrontal cortex and transcranial doppler ultrasonography of the middle cerebral artery. Blood biomarkers (lactate, cortisol and BDNF isoforms) and psychological responses (affect, physical and mental fatigue) were assessed at multiple time points. Linear mixed models revealed no significant interaction effects between time and condition for most outcomes, but lactate increased post-HIIE and psychological responses improved following HIIE compared to Rest. The single supervised HIIE bout was well-tolerated in this screened SCI sample. It did not affect subsequent cognitive performance but was associated with transient improvements in affect (PANAS-SF) and mental fatigue. Adequately powered studies are needed to determine whether HIIE confers cognitive benefits in individuals with SCI and to clarify underlying mechanisms.