Journal of General Internal Medicine

, Volume 33, Issue 6, pp 914–920 | Cite as

Effects of Sleep, Physical Activity, and Shift Work on Daily Mood: a Prospective Mobile Monitoring Study of Medical Interns

  • David A. Kalmbach
  • Yu Fang
  • J. Todd Arnedt
  • Amy L. Cochran
  • Patricia J. Deldin
  • Adam I. Kaplin
  • Srijan SenEmail author
Original Research



Although short sleep, shift work, and physical inactivity are endemic to residency, a lack of objective, real-time information has limited our understanding of how these problems impact physician mental health.


To understand how the residency experience affects sleep, physical activity, and mood, and to understand the directional relationships among these variables.


A prospective longitudinal study.


Thirty-three first-year residents (interns) provided data from 2 months pre-internship through the first 6 months of internship.

Main Measures

Objective real-time assessment of daily sleep and physical activity was assessed through accelerometry-based wearable devices. Mood scaled from 1 to 10 was recorded daily using SMS technology. Average compliance rates prior to internship for mood, sleep, and physical activity were 77.4, 80.2, and 93.7%, and were 78.8, 53.0, and 79.9% during internship.

Key Results

After beginning residency, interns lost an average of 2 h and 48 min of sleep per week (t = − 3.04, p < .01). Mood and physical activity decreased by 7.5% (t = − 3.67, p < .01) and 11.5% (t = − 3.15, p < .01), respectively. A bidirectional relationship emerged between sleep and mood during internship wherein short sleep augured worse mood the next day (b = .12, p < .001), which, in turn, presaged shorter sleep the next night (b = .06, p = .03). Importantly, the effect of short sleep on mood was twice as large as mood’s effect on sleep. Lastly, substantial shifts in sleep timing during internship (sleeping ≥ 3 h earlier or later than pre-internship patterns) led to shorter sleep (earlier: b = − .36, p < .01; later: b = − 1.75, p < .001) and poorer mood (earlier: b = − .41, p < .001; later: b = − .41, p < .001).


Shift work, short sleep, and physical inactivity confer a challenging environment for physician mental health. Efforts to increase sleep opportunity through designing shift schedules to allow for adequate opportunity to resynchronize the circadian system and improving exercise compatibility of the work environment may improve mood in this depression-vulnerable population.


medical education sleep disorders medical student and residency education 



We would like to personally thank Zhuo Zhao, Elena Frank, Jad Elharake, and all of the research assistants who are instrumental to running the Intern Health Study.

Prior Presentations

These findings were presented at the 2016 National Network of Depression Centers annual conference in Boulder, CO.


The funding sources had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. NIMH R01 MH101459 (Sen), NHLBI T32 HL110952 (Pack), and the University of Michigan Taubman Institute Internal Grant (Sen).

Compliance with Ethical Standards

This study was approved by the University of Michigan IRB and all subjects provided informed consent after receiving complete description of the study.

Conflict of Interest

Dr. J Todd Arnedt has received research funding from Eisai Co., Ltd. All other authors report no conflicts of interest.


  1. 1.
    Baglioni C, Battagliese G, Feige B, et al. Insomnia as a predictor of depression: a meta-analytic evaluation of longitudinal epidemiological studies. Journal of affective disorders. 2011;135(1):10–19.CrossRefPubMedGoogle Scholar
  2. 2.
    Ströhle A. Physical activity, exercise, depression and anxiety disorders. Journal of neural transmission. 2009;116(6):777–784.CrossRefPubMedGoogle Scholar
  3. 3.
    Sen S, Kranzler HR, Krystal JH, et al. A prospective cohort study investigating factors associated with depression during medical internship. Archives of general psychiatry. 2010;67(6):557–565.CrossRefPubMedPubMedCentralGoogle Scholar
  4. 4.
    Arora VM, Georgitis E, Woodruff JN, Humphrey HJ, Meltzer D. Improving sleep hygiene of medical interns: can the sleep, alertness, and fatigue education in residency program help? Archives of internal medicine. 2007;167(16):1738–1744.CrossRefPubMedGoogle Scholar
  5. 5.
    Baldwin Jr D, Daugherty SR. Sleep deprivation and fatigue in residency training: results of a national survey of first-and second-year residents. Sleep. 2004;27(2):217–223.CrossRefPubMedGoogle Scholar
  6. 6.
    Rye PL, Reeson ME, Pekrul CM, et al. Comparing health behaviours of internal medicine residents and medical students: an observational study. Clinical & Investigative Medicine. 2012;35(1):40–44.CrossRefGoogle Scholar
  7. 7.
    Mota MC, Waterhouse J, De-Souza DA, et al. Association between chronotype, food intake and physical activity in medical residents. Chronobiology International. 2016:1–10.Google Scholar
  8. 8.
    Olson EJ, Drage LA, Auger RR. Sleep deprivation, physician performance, and patient safety. CHEST Journal. 2009;136(5):1389–1396.CrossRefGoogle Scholar
  9. 9.
    Weinger MB, Ancoli-Israel S. Sleep deprivation and clinical performance. Jama. 2002;287(8):955–957.CrossRefPubMedGoogle Scholar
  10. 10.
    Kalmbach DA, Arnedt JT, Song PX, Guille C, Sen S. Sleep disturbance and short sleep as risk factors for depression and perceived medical errors in first-year residents. Sleep. 2017;40(3).Google Scholar
  11. 11.
    Williams AS, Williams CD, Cronk NJ, Kruse RL, Ringdahl EN, Koopman RJ. Understanding the exercise habits of residents and attending physicians: a mixed methodology study. Family medicine 2015;47(2):118–123.PubMedGoogle Scholar
  12. 12.
    Hull SK, DiLalla LF, Dorsey JK. Prevalence of health-related behaviors among physicians and medical trainees. Academic Psychiatry 2008;32(1):31–38.CrossRefPubMedGoogle Scholar
  13. 13.
    Sinsky C, Colligan L, Li L, et al. Allocation of physician time in ambulatory practice: a time and motion study in 4 specialties. Annals of Internal Medicine. 2016.Google Scholar
  14. 14.
    Guille C, Zhao Z, Krystal J, Nichols B, Brady K, Sen S. Web-based cognitive behavioral therapy intervention for the prevention of suicidal ideation in medical interns: a randomized clinical trial. JAMA Psychiatry. 2015;72(12):1192–1198.CrossRefPubMedPubMedCentralGoogle Scholar
  15. 15.
    Montgomery-Downs HE, Insana SP, Bond JA. Movement toward a novel activity monitoring device. Sleep and Breathing. 2012;16(3):913–917.CrossRefPubMedGoogle Scholar
  16. 16.
    Ferguson T, Rowlands AV, Olds T, Maher C. The validity of consumer-level, activity monitors in healthy adults worn in free-living conditions: a cross-sectional study. Int J Behav Nutr Phys Act. 2015;12(1):42.CrossRefPubMedPubMedCentralGoogle Scholar
  17. 17.
    Adam Noah J, Spierer DK, Gu J, Bronner S. Comparison of steps and energy expenditure assessment in adults of Fitbit Tracker and Ultra to the Actical and indirect calorimetry. Journal of medical engineering & technology. 2013;37(7):456–462.CrossRefGoogle Scholar
  18. 18.
    Foreman AC, Hall C, Bone K, Cheng J, Kaplin A. Just text me: using SMS technology for collaborative patient mood charting. Journal of Participatory Medicine. 2011;3:e45.Google Scholar
  19. 19.
    Walch OJ, Cochran A, Forger DB. A global quantification of “normal” sleep schedules using smartphone data. Science Advances. 2016;2(5):e1501705.CrossRefPubMedPubMedCentralGoogle Scholar
  20. 20.
    Team RC. R: a Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria. 2013. ISBN 3-900051-07-0; 2014.Google Scholar
  21. 21.
    Krueger C, Tian L. A comparison of the general linear mixed model and repeated measures ANOVA using a dataset with multiple missing data points. Biological research for nursing. 2004;6(2):151–157.CrossRefPubMedGoogle Scholar
  22. 22.
    Singer JD, Willett JB. Applied Longitudinal Data Analysis: Modelling Change and Event Occurrence. New York: Oxford University; 2003.CrossRefGoogle Scholar
  23. 23.
    Sen S, Kranzler HR, Didwania AK, et al. Effects of the 2011 duty hour reforms on interns and their patients: a prospective longitudinal cohort study. JAMA internal medicine. 2013;173(8):657–662.CrossRefPubMedPubMedCentralGoogle Scholar
  24. 24.
    Rosen IM, Gimotty PA, Shea JA, Bellini LM. Evolution of sleep quantity, sleep deprivation, mood disturbances, empathy, and burnout among interns. Academic Medicine. 2006;81(1):82–85.CrossRefPubMedGoogle Scholar
  25. 25.
    Kalmbach DA, Pillai V, Roth T, Drake CL. The interplay between daily affect and sleep: a 2-week study of young women. Journal of Sleep Research. 2014.Google Scholar
  26. 26.
    Kalmbach DA, Arnedt JT, Swanson LM, Rapier JL, Ciesla JA. Reciprocal dynamics between self-rated sleep and symptoms of depression and anxiety in young adult women: a 14-day diary study. Sleep Medicine 2017;33:6–12.CrossRefPubMedGoogle Scholar
  27. 27.
    Van Dongen HP, Maislin G, Mullington JM, Dinges DF. The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. SLEEP 2003;26(2):117–129.CrossRefPubMedGoogle Scholar
  28. 28.
    Drake CL, Roehrs T, Richardson G, Walsh JK, Roth T. Shift work sleep disorder: prevalence and consequences beyond that of symptomatic day workers. SLEEP. 2004;27(8):1453–1462.CrossRefPubMedGoogle Scholar
  29. 29.
    Kalmbach DA, Pillai V, Chen P, Arnedt JT, Drake C. Shift work disorder, depression, and anxiety in the transition to rotating shifts: the role of sleep reactivity. Sleep Medicine. 2015;16(12):1532–1538.CrossRefPubMedPubMedCentralGoogle Scholar
  30. 30.
    Association AP. DSM 5. American Psychiatric Association; 2013.Google Scholar
  31. 31.
    Medicine AAoS. International Classification of Sleep Disorders—Third Edition (ICSD-3). AASM Resource Library [online]. 2014.Google Scholar
  32. 32.
    Lockley SW, Barger LK, Ayas NT, Rothschild JM, Czeisler CA, Landrigan CP. Effects of health care provider work hours and sleep deprivation on safety and performance. Joint Commission Journal on Quality and Patient Safety. 2007;33(Supplement 1):7–18.CrossRefPubMedGoogle Scholar
  33. 33.
    Giacobbi PR, Hausenblas HA, Frye N. A naturalistic assessment of the relationship between personality, daily life events, leisure-time exercise, and mood. Psychology of Sport and Exercise. 2005;6(1):67–81.CrossRefGoogle Scholar
  34. 34.
    Peluso MAM, Andrade LHSGd. Physical activity and mental health: the association between exercise and mood. Clinics. 2005;60(1):61–70.CrossRefPubMedGoogle Scholar
  35. 35.
    Meltzer LJ, Hiruma LS, Avis K, Montgomery-Downs H, Valentin J. Comparison of a commercial accelerometer with polysomnography and actigraphy in children and adolescents. Sleep. 2015;38(8):1323.CrossRefPubMedPubMedCentralGoogle Scholar
  36. 36.
    Serkh K, Forger DB. Optimal schedules of light exposure for rapidly correcting circadian misalignment. PLoS Comput Biol. 2014;10(4):e1003523.CrossRefPubMedPubMedCentralGoogle Scholar
  37. 37.
    Eastman CI, Burgess HJ. How to travel the world without jet lag. Sleep medicine clinics. 2009;4(2):241–255.CrossRefPubMedPubMedCentralGoogle Scholar
  38. 38.
    Crowley SJ, Lee C, Tseng CY, Fogg LF, Eastman CI. Combinations of bright light, scheduled dark, sunglasses, and melatonin to facilitate circadian entrainment to night shift work. Journal of Biological Rhythms. 2003;18(6):513–523.CrossRefPubMedGoogle Scholar

Copyright information

© Society of General Internal Medicine 2018

Authors and Affiliations

  • David A. Kalmbach
    • 1
  • Yu Fang
    • 2
  • J. Todd Arnedt
    • 1
  • Amy L. Cochran
    • 3
  • Patricia J. Deldin
    • 1
  • Adam I. Kaplin
    • 4
  • Srijan Sen
    • 1
    • 2
    Email author
  1. 1.Department of Psychiatry University of Michigan Medical SchoolAnn ArborUSA
  2. 2.Molecular and Behavioral Neuroscience InstituteUniversity of MichiganAnn ArborUSA
  3. 3.Department of MathematicsUniversity of MichiganAnn ArborUSA
  4. 4.Departments of Psychiatry and NeurologyJohns Hopkins University School of MedicineBaltimoreUSA

Personalised recommendations