“I don’t have to convince anyone how important sleep is,” said Dr. Tracy Jill Doty, opening her session at the 2020 Performance Psychology Summit last week.
The Consortium for Health and Military Performance at the Uniformed Services University and the Walter Reed Army Institute of Research (WRAIR) Center for Military Psychiatry and Neuroscience hosted the 2020 Performance Psychology Summit, Nov. 12-13.
Doty, Chief of the Sleep Research Center at WRAIR in Bethesda, Md., has been studying the effects of sleep and sleep deprivation for the Army.
“We’ve been talking about sleep as a force multiplier a lot during this summit, and it is,” she said. “It makes your team better.”
Sleep is a problem in the military according to Doty. Seven to nine hours is needed but two-thirds of Soldiers don’t get enough sleep to be healthy, twice as many as in the civilian population.
“Not enough sleep can cause negative moods and a weakened immune system,” said Doty. “Chronic sleep loss is linked to many mood disorders, diabetes and obesity.”
Doty also focused on the effects of caffeine on sleep.
She mentioned a new tracking tool called 2B-Alert Web, an online tool that predicts the alertness of an "average" individual as a function of their sleep/wake schedule, caffeine consumption, and time of day.. The web tool is available for free at https://sleep.bhsai.org, by registering to create an account. It gives performance and caffeine recommendations based on group data
and also provides optimal caffeine schedules for user-provided periods of desired peak alertness.
Per the directions in their website, ”users manually enter a sleep/wake/peak alertness schedule, as well as caffeine dosing and timing, and the tool will display the corresponding predictions for three different statistics of alertness on the psychomotor vigilance task (PVT).
If the user provides the desired period of peak alertness, the system will output the estimated optimal caffeine schedules. The tool predicts alertness for the duration of the given schedule and 48 hours of subsequent total sleep deprivation.”
According to their website, this tool can be used to:
- Assess the effect of different sleep/wake schedules and caffeine consumption
- Design sleep/wake and caffeine schedules to optimize alertness
- Generate hypotheses that can be experimentally tested
- Optimize the benefits of caffeine use
Doty also spoke of a study she and her team conducted on the effects of caffeine and sleep.
“For the caffeine study we used caffeine gum, a product developed by our group that is now available on Amazon and in some rations for special forces, ”said Doty. “We had two teams, forty-eight individuals took part in the sleep-deprivation/caffeine study, which was placebo-controlled and double-blind.”
“The participants were restricted to five hours of sleep per night for five days. During their awake periods they were given either caffeine in pill form, or placebo pills, twice each day,” Doty said.
Doty said that for comparison purposes, an 8 oz. cup of coffee can contain anywhere from 95-200 milligrams of caffeine. Each day the sleep-deprived subjects' cognitive abilities were assessed several times with a battery of tests.
“Compared to placebo, the caffeine pills improved cognitive function in these sleep-deprived people — but only for two days,” she said. “After that, the effect was essentially nil.”
The message is that caffeine will counteract the effects of sleep deprivation, but only for a short time.
So don’t depend on that coffee to get you through the long term.