Research

Hormonal

The contribution of nitric oxide to exercise hyperaemia (blood flow increase during exercise) is significant (20-30%) but not obligatory, with redundancy in vasodilator mechanisms allowing other pathways to compensate.

While nitric oxide helps increase blood flow during exercise, your body has backup systems (like prostaglandins) that ensure blood flow increases even if NO is blocked. This means you don't need to worry about 'blocking' NO to get benefits; the body adapts.

ModerateQualifiesMEDIUM confidence
The contribution of NO to exercise hyperaemia in humans therefore appears to be of around 20–30%, but redundancy exists and NO may not be obligatory for the hyperaemia observed during exercise.
Daniel J. Green et al. · The Journal of Physiology · 2004

Why this rating

The paper highlights controversy and methodological limitations in measuring this, citing conflicting studies.

Source

Effect of exercise training on endothelium‐derived nitric oxide function in humans

Daniel J. Green et al. · The Journal of Physiology · 2004

DOI 10.1113/jphysiol.2004.068197

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DOI resolved against Crossref · corpus check 2026-06-10

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