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Background: A novel concept of controlled, short-duration supramaximal HIIT enables 3-4 times higher exercise intensities with reduced dyspnea, compared to moderate-intensity continuous training (MICT) in people with COPD. However, its effects on neurotrophic factors and brain health are yet to be investigated. We aimed to examine the acute response of neurotrophic factors to supramaximal HIIT and MICT in people with COPD.

Methods: Sixteen people with mild to severe COPD (75±6 years; 73±13 FEV1%pred) underwent supramaximal HIIT (comprising 10x6 sec intervals interspersed with 54 sec rest) and MICT (20 min at 60% CPET Wpeak). Supramaximal HIIT was performed at two intensities (HIIT60% and HIIT80%). We measured plasma levels of brain-derived neurotrophic factor (BDNF), irisin, cathepsin B and clusterin pre- and post- exercise.

Results: BDNF increased after both HIIT and MICT (Fig 1). Clusterin increased during HIIT80% (19940 [−35900 to 49600] ng/mL, +11%, p=0.01) and MICT (23390 [−5060 to 51010] ng/mL, +12%, p=0.03), but not HIIT60% (−1100 [−10060 to 113600] ng/mL, -1%, p=0.85). No changes were seen in irisin or cathepsin B.

Conclusion: For the first time, we showed that in COPD, supramaximal HIIT induces a similar increase in BDNF as MICT, with half the exercise duration. Supramaximal HIIT might be a viable exercise modality in COPD, while its long-term effects on brain health remain to be investigated.