NatureContemporaryAustraliahigh confidence

Mark Visser said he could hold his breath for 6 minutes and 4 seconds.

Notes on verification

The quote is directly attributed to Visser in ABC News and corroborated by USC press release and other independent sources, though the underlying breath-hold time itself is self-reported and not independently measured. [cascade flags: wikipedia_dropped_other_sources_exist | tier=silver indep_score=0.875 clusters=2 claim_tier=notable | kind=attributed eligibility=high]

Sources