Toward a hyperventilation detection system in freediving: a proof of concept using force sensor technology

• DOI: 10.3389/fphys.2024.1498399
• Publication Date: 2025-01-06T07:03:20Z
• Authors: Frank Pernett; Eric Mulder; Filip Johansson; Arne Sieber; Ricardo Bermudez; Marcus Lossner; Erika Schagatay
• Keywords: Proof of concept

Hyperventilation before breath-hold diving (freediving) is widely accepted as a risk factor for hypoxic syncope or blackout (BO), but there no practical way to address it dives. This study explores the feasibility of using force sensor predict end-tidal carbon dioxide (P ETCO2) assess hyperventilation in freedivers. Twenty-one freedivers volunteered participate during two national competitions. The divers were instructed breathe normally and perform three dry apneas 1, 2, 3-min duration at 2-min intervals sitting position. Before after apneas, P ETCO2 was recorded. signal from sensor, attached chest belt, used record frequency amplitude movements, product these values 60 s apnea ETCO2. mean below 35 mmHg all apneas. increased 1 3 (p < 0.001), while respiratory rate similar (NS). explained 34% variability third apnea. shows that can estimate static apnea, providing basis further research. More studies are needed confirm its effectiveness preventing issues. Freedivers may hyperventilate without noticing it, such system could improve awareness this condition. Additional underwater tests essential determine whether enhance safety freediving.