Circadian Rhythm and Its Effect On the Performance of Technical Services Engineers

References

[1] K. E. Andaya, “Quality of Sleep Among Shift Work Nurses at the Baguio General Hospital: A Pilot Cross-Sectional Study,” Philippine Journal of Otolaryngology Head and Neck Surgery, vol. 37, no. 2, p. 26, 2022. 10.32412/pjohns.v37i2.2023.

[2] D. Angrave, A. Charlwood, and M. Wooden, “Long Working Hours and Physical Activity,” Journal of Epidemiology & Community Health, vol. 69, no. 8, pp. 738–744, 2015. 10.1136/jech-2014-205230.

[3] V. Ayala, M. Martínez-Bebia, J. A. Latorre, N. Gimenez-Blasi, M. J. Jimenez-Casquet, J. Conde-Pipo, A. Bach-Faig, and M. Mariscal- Arcas, “Influence of Circadian Rhythms on Sports Performance,” Chronobiology International, vol. 38, no. 11, pp. 1522–1536, 2021.

[4] K. G. Baron and K. J. Reid, “Circadian Misalignment and Health,” International Review of Psychiatry, vol. 26, no. 2, pp. 139– 154, 2014. 10.3109/09540261.2014.911149.

[5] M. Barten, “Aviation Industry: All You Need to Know About the Aviation Sector,” Revfine.com, Jun. 6, 2024. [Online]. Available: https://www.revfine.com/aviation-industry

[6] D. B. Boivin, P. Boudreau, and A. Kosmadopoulos, “Disturbance of the Circadian System in Shift Work and Its Health Impact,” Journal of Biological Rhythms, vol. 37, no. 1, pp. 3 –28, 2021. 10.1177/07487304211064218.

[7] R. Bosano, “Experts Sound the Alarm on Filipinos’ Lack of Quality Sleep,” ABS-CBN News, Mar. 22, 2025. [Online]. Available: https://www.abs-cbn.com/news/health- science/2025/3/22/experts-sound-the-alarm-on- filipinos-lack-of-quality-sleep-0919

[8] D. Christensen, “What is the Safest Mode of Transportation – 2025 Updated,” Team Justice, Mar. 17, 2025. [Online]. Available: https://teamjustice.com/safest-mode-of- transportation

[9] National Institute of General Medical Sciences, “Circadian Rhythms,” [Online]. Available: https://www.nigms.nih.gov/education/fact- sheets/Pages/circadian-rhythms

[10] A. Fry and A. Rehman, “Sleep, Athletic Performance, and Recovery,” Sleep Foundation, Dec. 13, 2023. [On line]. Available: https://www.sleepfoundation.org/physical- activity/athletic-performance-and-sleep

[11] I. Geneva, “Human Body Temperature Circadian Rhythm in Health and Disease,” IntechOpen eBooks, 2024. 10.5772/intechopen.1003852.

[12] N. W. Gentry, L. H. Ashbrook, Y. Fu, and L. J. Ptáček, “Human Circadian Variations,” Journal of Clinical Investigation, vol. 131, no. 16, 2021.

[13] International Labour Organization Country Office for the Philippines et al., The Impact of Trade on Employment in the Philippines: Country Report, 2019.

[14] J. Johnson, “What to Know About Circadian Rhythm,” Medical News Today, Jan. 11, 2021. [Online]. Available: https://www.medicalnewstoday.com/articles/ci rcadian-rhythms

[15] J. Khan, “Take Advantage of Your Circadian Rhythm for Peak Productivity,” Rise Science, 2024. [Online]. Available: https://www.risescience.com/blog/circadian- rhythm-sales-productivity

[16] Labor Law PH, “Night Shift Differential Pay,” Apr. 20, 2025. [Online]. Available: https://laborlaw.ph/night-shift-differential-pay

[17] Lark Editorial Team, “Night Shift Maintenance (10pm-6am),” Jan. 29, 2024. [Online]. Available: https://www.larksuite.com/en_us/topics/work- shift-schedule/night-shift-maintenance-10pm- 6am

[18] J. Lozano et al., “Shift Work Research in the Philippines: Current State and Future Directions,” Philippine Science Letters, vol. 1, no. 1, 2012. [Online]. Available: https://scienggj.org/2012/2012n1.4p4.pdf

[19] S. Lu and J. Lu, “Assessing the Association Between the Night Shift Schedule and Mental Health Symptoms Among Filipino Women Factory Workers: A Cross-Sectional Study,” Journal of International Women’s Studies, vol. 22, no. 1, pp. 312–329, 2012. [Online]. Available: https://vc.bridgew.edu/jiws/vol22/iss1/18

[20] F. Lu et al., “The Effect of Shift Work and Poor Sleep on Self-Reported Skin Conditions: A Survey of Call Center Agents in the Philippines,” Clocks & Sleep, vol. 1, no. 2, pp. 273–279, 2019. 10.3390/clockssleep1020023.

[21] C. I. P. Lugay Jr. et al., “Evaluation of Circadian Rhythmic Activity Cycle in Line with Academic Activities Among Engineering Students Studying in NCR During an Online Setup,” Proceedings of the International Conference on Industrial Engineering and Operations Management, 2023. [Online]. Available: https://ieomsociety.org/proceedings/2023manil a/502.pdf

[22] J. M. McFarlane, “Biological Rhythms,” Pressbooks, Aug. 22, 2024. [Online]. Available: https://opentextbc.ca/psychologymtdi/chapter/b iological-rhythms

[23] F. Melissa, “How Core Body Temperature Affects Athletic Performance,” HeatSense, Mar. 7, 2025. [Online]. Available: https://heatsense.com/blogs/the-heat-beat/how- core-body-temperature-affects-athletic- performance

[24] National Institute of General Medical Sciences, “Circadian Rhythms,” NIH, 2023. [Online]. Available: https://www.nigms.nih.gov/education/fact- sheets/Pages/circadian-rhythms.aspx

[25] J. Pett and P. Mavroudis, “Hot Topics in Systems Biology 2023: Clock Genes and Circadian Rhythm Regulation,” Frontiers in Systems Biology, 2024. [Online]. Available: https://www.frontiersin.org/research- topics/57370

[26] S. Reddy, V. Reddy, and S. Sharma, “Physiology, Circadian Rhythm,” StatPearls - NCBI Bookshelf, May 1, 2023. [Online]. Available: https://www.ncbi.nlm.nih.gov/books/NBK519 507

[27] M. Samel, “Graveyard Shift Meaning: Pros & Cons of Late Night Shifts,” PARiM Workforce Software, 2024. [Online]. Available: https://parim.co/blog/graveyard-shift

[28] N. Silver, “Everything to Know About Your Circadian Rhythm,” Healthline, Jan. 22, 2025. [Online]. Available: https://www.healthline.com/health/healthy- sleep/circadian-rhythm

[29] Skybrary, “Maintenance Workload,” Skybrary Aero, 2024. [Online]. Available: https://skybrary.aero/articles/maintenance- workload

[30] J. M. Thomas et al., “Circadian Rhythm Phase Shifts Caused by Timed Exercise Vary with Chronotype,” JCI Insight, vol. 5, no. 3, e134270, 2020. 10.1172/jci.insight.134270.

[31] K. P. Wright, J. T. Hull, and C. A. Czeisler, “Relationship Between Alertness, Performance, and Body Temperature in Humans,” AJP Regulatory Integrative and Comparative Physiology, vol. 283, no. 6, pp. R1370–R1377, 2002. 10.1152/ajpregu.00205.2002.

@article{1712774,
      author = {Carlos Miguel De Guzman},
      title = {Circadian Rhythm and Its Effect On the Performance of Technical Services Engineers},
      journal = {Iconic Research And Engineering Journals},
      year = {2025},
      volume = {9},
      number = {6},
      pages = {830-836},
      issn = {2456-8880},
      url = {https://www.irejournals.com/formatedpaper/1712774.pdf},
      abstract = {This study examines the influence of circadian rhythm on the physical and mental performance of Technical Services Engineers at Lufthansa Technik Philippines. Unlike flight crews and mechanics with regulated schedules, these engineers often work irregular shifts, including afternoons and nights, potentially disrupting biological cycles. Using a cross-sectional design, data on body temperature, sleep duration, work hours, and shift schedules were collected to assess circadian rhythm. Physical performance was measured via grip strength, and mental performance through a validated aptitude test. Results indicate that individual circadian peaks, reflected by body temperature, align with optimal performance, though no significant predictive relationship was found across grouped variables. However, notable performance differences emerged between minimum and maximum temperature conditions, suggesting that synchronizing work schedules with circadian peaks may improve efficiency. Recommendations include personalized scheduling, strategic rest during circadian lows, and further research with larger samples and expanded performance metrics to enhance fatigue risk management in aviation maintenance.},
      keywords = {Aviation maintenance, circadian rhythm, fatigue risk management, performance optimization, shift work, technical services engineers.},
      month = {December},
      doi = {https://doi.org/10.64388/IREV9I6-1712774}
  }