Sleeping in Extreme Conditions: A Case Study of a 2024 Vendée Globe Skipper

This case study measured the 2024 Vendée Globe winner's sleep, examined the influence of contextual factors on sleep, and described the perceived relationship between sleep and performance.

Sleep was measured onshore using actigraphy and at sea using a dedicated onboard sleep-monitoring tool. Each sleep episode was manually initiated and terminated by the skipper via a computer, followed by a self-rated sleep quality score. Wind force/angle, boat speed, and air temperature were collected. A semistructured interview was conducted postrace.

Over 64 days, 19 hours, 22 minutes, and 49 seconds, the skipper adopted a polyphasic sleep pattern (41.3 [10.5] episodes/24 h) characterized by a mix of independent sleep opportunities and clustered sleep attempts separated by microawakenings. Average time in bed (8h22 [2h20]) and total sleep time (6h30 [1h55]) per day were comparable to onshore values (8:03 [0:31], 6:23 [0:25]). Forty-nine percent of episodes were rated moderate to good. Nighttime episodes (9:00 PM-6:00 AM) were overrepresented, suggesting circadian rhythm preservation. Interview data identified 5 functional-impairment moments and 2 peak-functioning periods, which temporally coincided with decreasing and increasing 24-hour rolling sleep, respectively. Wind angle modestly influenced sleep duration.

Despite extreme constraints of solo ocean racing, proactive in-race sleep management allowed the skipper to maintain his habitual sleep quantity/quality close to onshore baseline levels. A temporal coincidence appears to exist between operational functioning, fluctuations in 24-hour rolling sleep, and in-race major difficulties. Findings suggest that in-race "opportunistic sleep accumulation" strategies may improve performance and safety in solo offshore racing.