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Welcome to the Crew Endurance Resources Library
- Circadian-based Watchbills: Design, implement and assess innovative watchbills that support human circadian rhythms; test these out in operational environments.
- Current Status: Significant progress made on DDGs and CGs. Collected data during 19-day underway on amphib (LSD 48). Analysis is ongoing.
- Planned: Collect data on submarines and PCs. Develop fleet-wide survey to assess policy compliance and watchbill efficacy.
- Crew Endurance Training: Develop training systems to instruct leadership/commands and Sailors on the need to prioritize sleep to enhance warfighter readiness using instructor-led and individual web-based training.
- Current Status: Significant progress made. First delivery to SWOS and Recruit Training Command in November 2019.
- Planned: Work on train the trainer materials and integrate into updated Crew Endurance website.
- Dietary Patterns of Night Watchstanders: Night shift workers often struggle to maintain healthy diets, especially on US Navy ships. The food served at night, “midrats”, is often left over from previous meals rather than a planned, nutritious meal. These same Sailors almost always labor under a significant and ever-increasing sleep debt. One of the unfortunate consequences of sleep deprivation and circadian misalignment is an imbalance in two hormones: excess ghrelin and insufficient leptin. The former contributes to the cravings for carbohydrates while the latter results in not feeling full or satiated. This combination creates the perfect situation for weight gain.
- Planned: Study the food intake of USN watchstanders during underway operations, measuring fluctuations in glucose levels of Sailors with various dietary plans.
- Sailors CR-53 Increased Manning: Study two DDGs in Basic Phase to assess the effects of additional manning on ship-wide metrics and individual crewmember performance.
- Current Status: Data collection and analysis has been completed. Preliminary results were provided to CNSF Aug-Sep 2019.
- Planned: Technical report will integrate findings from the two related efforts.
- Light Management: Manage high-energy visible (HEV) light exposure for shift workers using blue blockers and multiple versions of HEV emitters. The development of multiple means of administering HEV light may help speed up circadian entrainment process.
- Current Status: Significant progress with procurement of multiple light sources including patented delivery systems.
- Planned: Install HEV emitting light systems on DDG and CSS-1 submarine in early 2020.
- Habitability Enhancements for Ships: We have developed innovative rack curtains for sleeping quarters that limit light (and potentially noise) exposure outside the rack.
- Current Status: Significant progress has been made with new rack curtains to be installed on a DDG for study during underway operations. Once installed in all ~300 racks, our team will assess the sleep of Sailors ~1 week before and after installation.
- Planned: Develop a "smart rack" that tracks the physiological conditions of the occupant and administers light on the appropriate schedules.
- Stress Inoculation Training: Stress Inoculation Training (SIT) for improving performance under intensely stressful situations; designing safe and effective methods for inducing stress during training.
- Current Status: Baseline and initial data collections conducted at SWOS. Another study is ongoing at NPS using a ship bridge simulator and a cold pressor (ice bucket) stress.
- Planned: Studies over the next year will assess cortisol and physiological indicators of stress with insights and feedback to SWOS.
- Sleep Inertia Mitigation: Identify and test mitigation strategies for reducing sleep inertia when individuals are awakened from deep sleep.
- Current Status: Two sleep inertia studies have been designed and one has been carried out with NASA Ames Research Center.
- Planned: Two data collections are scheduled over the next 18 months, one at NPS and another with a partner at a university sleep lab.
- Dark Adaptation: Methods to assess how HEV light can be used to increase alertness (e.g., supplementing light in CIC) while also protecting dark adaptation (e.g., bridge watchstanders.) Monocular vs binocular tests are planned.
- Current Status: "Pirate" study has been designed and submitted for IRB approval.
- Planned: First data collection scheduled for Winter 2020 with salivary melatonin using DLMO technique.
The 3/9 Circadian Watch Rotation
The 6/18 Circadian Watch Rotation
The 4/8 Circadian Watch Rotation
The D5/N3 Circadian Watch Rotation
- Prior to Watch: Notify your watch supervisor, including the reason for fatigue (sickness, training and shipboard evolution, etc.) and request to switch watches. Watch supervisors will report the switch to the Senior Watch Officer.
- While on Watch: Notify your watch supervisor, so that a switch can be made promptly. If you are experiencing micro-sleeps or cannot stay awake, call
Chapter by Shattuck, N.L and Matsangas, P. in Vermetten, E., Germain, D. & Neylan, T.
(Eds.), Sleep and Combat related PTSD. Springer, 2018
Chapter by Shattuck, N.L., Matsangas, P., Mysliwiec, V., and Creamer, J.L. in Schnyer, D. 7
Matthews, M.D (Eds.), Human Performance Optimization: The Science and Ethics of
Enhancing Human Capabilities.Oxford University Press, New York
Chapter by Drillings, M., Knapp, B., and Shattuck, N.L., in D. Boehm-Davis, Durso, Lee,
(Eds.), The APA Handbook of Human Systems Integration. Washington, DC: American
Psychological Association. 2015
Chapter by Miller, N.L., Matsangas, P., and Kenney, A. in J. Laurence and M. D. Matthews
(Eds.), The Oxford Handbook of Military Psychology. New York: Oxford University Press, 2012.
Chapter by Miller, N.L., Matsangas, P. and Shattuck, L.G in P.A. Hancock and J.L Szalma
(Eds.),Performance Under Stress. Mahwah, NJ: Ashgate Publications, 2007
Chapter by Miller, N.L., Crowson., J.J., and Narkevicius, J.M. in H.R. Booher (Ed.),
Handbook of Human Systems Integration. New York: John Wiley and Sons, 2003
The New York Times, October 2018, Tim Herrera
NavyTimes, October 2018, Geoff Ziezulewicz
U.S Naval Institute Proceedings Magazine, March 2018, Captain John Cordle USN (Ret)
LIVESTRONG, February 2018, Bryn Huntpalmer
U.S. Naval Institute, September 2017, Captain John Cordle USN (Ret)
The prize was awarded to three scientists for their work in the discovery of the mechanism of
circadian rhythms in all organisms
Reuters, September 2017, Marilynn Larkin
The Guardian, September 2017, Rachel Cooke
CNN Health, August 2017, Sandee LaMotte
United States Naval Institute Proceedings Magazine, July 2017, Machine Mate Nuclear Chief Jay Holley, USN.
Provides a great perspective on how important it is to give Sailors the opportunity to sleep
TIME, February 2017, Alice Park
U.S. Naval Institute Proceedings Magazine, August 2016, Captain John Cordle USN (Ret)
Huffington Post, July 2016, Sarah DiGiulio
Van Winkles, October 2015, Peter S. Green
U.S. Naval Institute, 30 August 2015, LCDR Katie Jacobson
National Public Radio, april 2014, Alan Yu
NavyTimes, October 2013, Sam Fellman
United States Naval Institute Proceedings Magazine, January 2013, Captain John Cordle USn
(Ret) and Dr. Nita Shattuck
This article won the Surface Navy Association Literary Award for 2013.
The SNA Literary Award recognizes the best professional article in any publication
addressing Surface Navy or surface warfare issues.
NavyTimes, June 2012, Gidget Fuentes and Tony Lombardo
Includes training for emergency responders to reduce the risks associated with long work
hours and information on how to cope with shiftwork
A nonprofit organization in the USA. Their mission is to improve public health and safety by
achieving understanding of sleep and sleep disorders, as well as to support sleep-related
education, research, and advocacy
Information on how to manage stress and fatigue levels
Many resources on sleep and safety including a large number of videos and articles
Resources for managing sleep and fatigue
A site dedicated to exploring the positive benefits of sleep health
Resources on Total Force Fitness including the Performance Triad initiative started by the
Department of Defense and in trial phase at various military installations.