Skip to Content
Crew Endurance

Web Content Display Web Content Display

Explore the Knowledge Center

Nested Portlets Nested Portlets

Web Content Display Web Content Display

Welcome to the Crew Endurance Resources Library

Learn more about sleep and what it can do for you, the crew, and the nation's defense

  • 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


Revised 9.19.2019
Reference (a)  CNSP / CNSL INST 3120.2 of 30 Nov 2017 – Comprehensive Fatigue and Endurance Management Policy
1. Crew Fatigue and Endurance Management
a.  The combat readiness of USS XXXXX depends on the individual readiness of each sailor onboard. Research has shown that humans require 8 hours (on average) of uninterrupted sleep each night to function effectively. This means allowing 9 hours for prep and transition into sleep. Even a small deficit in sleep for a few days can lead to impaired judgement, slow reaction times and decreased physical readiness. Getting proper rest yields the clear mind and combat edge we need to win, and we cannot afford to yield this advantage to our adversaries.
  b. I expect leaders up and down the chain of command do their utmost to provide 8 hours of uninterrupted sleep availability to every crew member, and prevent needlessly fatiguing the crew. In turn, I expect each member USS XXXXXX to make every effort to manage their own individual crew rest at all times.  You would not take the watch drunk or if you lacked qualifications - do not take the watch fatigued.
c.  The requirement to sleep does not mean that there will not be occasions when other requirements interfere with watch routines.  Supervisors must use all available tools to plan ahead for PMS, corrective maintenance, drills and training to ensure that workload is predictable and shared equitably, and take corrective actions as necessary to mitigate the impact of emergent events. If you reach a point where work must be deferred due to fatigue or to preserve sleep prior to watch, notify your supervisor for guidance.
2. Actions. The following provisions will be observed daily onboard USS XXXX to ensure adequate crew rest:
a. USS XXXXX will preserve proper sleeping conditions including noise discipline, light discipline in berthing areas and adjacent spaces from 1900 until the conclusion of late sleepers, usually 0900. 
b. Personal devices with lit screens including smart phones, smart phones, tablets and laptops will be secured from 1900 until the conclusion of late sleepers due to their ill effects on sleep and wakefulness cycles.
c. Routine operations, evolutions, drills, and training will not be planned from 1900 until the conclusion of late sleepers, usually 0900. 
d. Ship-wide announcements of an administrative nature will be kept to a minimum, planned from 1900 until the conclusion of late sleepers, usually 0900.
e. I will have a non-punitive policy for any member who takes the initiative to request watch relief due to fatigue.  The safety of the ship is more important than saving face. If you feel that you may be ineffective on watch due to fatigue, then you have a duty to your shipmates to take action. This means that self-reporting will not incur punitive action for missing a watch.
  • 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   
f. Watches will be scheduled on a circadian basis whenever possible, meaning that watches will add up to a 24-hour period [in accordance with USS XXXXXXX Notice XXXXXXX]. Notify the XO or Senior Watch Officer promptly if this is not possible.
3.  Routine Evolutions and Briefings.
a. Crew rest shall be discussed as part of operational risk management and individual risk management, and as part of all pre-evolution briefs.
b. Briefings for any evolution onboard USS XXXXX will include the following statement: “If any member of this evolution feels they have not had enough rest to perform it safely, see myself or the XO immediately so we can find a replacement for you.” 
c. Unplanned evolutions will occur. Adherence to this standing order will improve your resilience to ensure that you are better prepared for casualty response (such as fire, flooding or medical emergency). You enter battle with the sleep you have.  After the evolution is complete, supervisors must review the schedule for all personnel under their purview to ensure that they do not have follow-on duties that will be impacted by the interruption to their normal routine.



      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.

Web Content Display Web Content Display


Web Content Display Web Content Display


NPS’ Sleep Study Research Leads to Fleetwide Policy

Web Content Display Web Content Display

Matt Walker: Sleep is your Superpower

Web Content Display Web Content Display

What Makes You Tick: Circadian Rhythms

Navigation Navigation