A study by Pepperdine University found sailors under high stress and facing long working hours showed even more signs of stress and lower readiness when using caffeine and other stimulants.
Sailors routinely work with short rest for months at sea. Energy drinks make it easier for sailors to become chronically sleep deprived, said John Cordle, a human factors engineer who studies sleep deprivation for the Navy in Hampton Roads.
“It's eight o'clock at night and you slug a coffee to keep going,” he said. “And then finish your watch at 10 o'clock and you're supposed to go to bed to sleep until seven but your body's still hyped up from the caffeine. It's gonna take hours for that to go down.”
Sailors routinely have 100-hour work weeks while at sea. The hours have increased as the Navy copes with recruiting shortages.
Energy drinks are a staple in ship stores and at bases around the country. Senior leaders are slowly acknowledging the problem, Cordle said.
“I grew up in a world where I would say lack of sleep was like a badge of honor,” he said. “Like, the more tired you are, the harder you work. I think that's changing.”
Alarm bells were set off around the fleet when lack of sleep was found to contribute to two separate collisions by Navy ships in 2017, killing seven sailors on USS Fitzgerald. Rules were put in place so sailors would at least have consistent sleeping times, Cordle said.
The Pepperdine study found caffeine did have a small benefit for people under moderate stress for short periods of time. The problem increases under the consistently high stress environment in the Navy as well as civilian professions like police and fire, where lack of sleep is compounded over time.
The study, which surveyed 15,880 Navy personnel, was published in the March issue of Occupational Health Science.
