Why the study?
Freediving standards recommend recovery intervals twice the dive duration between repeated dives, but this has yet to be supported by scientific evidence.
Do repeated freedives to 11 metres of freshwater with standard recovery intervals increase the rate of arterial oxygen desaturation in recreational freedivers?
Population
Six recreational freedivers
Comparison
Three serial freedives to 11 mfw separated by 2 min 30 s recovery intervals
Design
Physiological observational study
Key result
Repeated freedives to 11 metres with 2.5-minute recovery intervals led to progressively lower median SpO2, reaching 82.5% after the third dive compared to 99.5% at baseline (P<0.01).
Authors
Loading...
Short recoveries may accelerate desaturation in repeated freedives; leaves open optimal intervals for hypoxia prevention.
Observational (n=6)
Do repeated freedives to 11 metres of freshwater with standard recovery intervals increase the rate of arterial oxygen desaturation in recreational freedivers?
Absolute Event Rate: 82.5% vs 99.5%
p-value: p=<0.01
Repeated freedives with standard recovery intervals lead to progressively increased arterial oxygen desaturation, suggesting current recovery guidelines may be insufficient for safe serial diving.
Mulder et al. (2023) conducted an observational in Recreational freedivers (n=6). Repeated freedives to 11 metres of freshwater vs. Baseline was evaluated on Peripheral oxygen saturation (SpO2) (p=<0.01). Repeated freedives to 11 metres with 2.5-minute recovery intervals led to progressively lower median SpO2, reaching 82.5% after the third dive compared to 99.5% at baseline (P<0.01).