Understanding how nighttime railway noise and vibration affect sleep and blood markers of metabolic health

ISRCTN ISRCTN84840541
DOI https://doi.org/10.1186/ISRCTN84840541
Swedish Transport Administration (Trafikverket) grant TRV 2025/13983
Sponsor University of Gothenburg
Funder Trafikverket
Submission date
26/01/2026
Registration date
28/01/2026
Last edited
28/01/2026
Recruitment status
Not yet recruiting
Overall study status
Ongoing
Condition category
Nervous System Diseases
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
This study explores how rail freight noise and vibration affect sleep, heart function, metabolism, and thinking skills. The goal is to understand how typical urban noise and vibration may influence overall health and daily functioning.

Who can participate?
Healthy adults aged 18–30 years living in the Gothenburg area with normal hearing, regular sleep patterns, no diagnosed sleep disorders, and not using sleep medication.

What does the study involve?
Participants will spend five nights in a sleep laboratory. The first night is for acclimatization. The following nights include one quiet night and three nights with simulated rail noise and vibration. Sleep, heart function, and activity will be monitored using non-invasive sensors. Each morning, participants will give a small blood sample and complete cognitive tests. Questionnaires and wrist monitoring will track sleep, alertness, and daily activity.

What are the possible benefits and risks of participating?
There is no direct benefit. Risks are minimal and may include mild sleep disturbance, temporary discomfort from wearing sensors, or minor discomfort and bruising from blood sampling.

Where is the study run from?
University of Gothenburg, Sweden.

When is the study starting and how long is it expected to run for?
February 2026 to June 2026, with each participant involved for five nights.

Who is funding the study?
The Swedish Transport Administration (Trafikverket)

Who is the main contact?
Michael Smith MSc PhD, michael.smith@amm.gu.se

Contact information

Dr Michael Smith
Principal investigator, Public, Scientific

Department of Occupational and Environmental Medicine, School of Public Health and Community Medicine
Institute of Medicine, Sahlgrenska Academy, University of Gothenburg
Mailing address
Box 453, Arbets- och miljömedicin, University of Gothenburg, Gothenburg 405 30, Sweden
Visiting address
Guldhedsgatan 5A, Gothenburg 413 20
michael.smith@amm.gu.se
Phone no: 031-7862843
Gothenburg
41320
Sweden

ORCiD logo 0000-0001-8541-9625
+46 031-7862843
michael.smith@amm.gu.se

Study information

Primary study designInterventional
AllocationRandomized controlled trial
MaskingBlinded (masking used)
ControlDose comparison
AssignmentCrossover
PurposeBasic science, Health services research
Scientific titleCombined effects of railway noise and vibration on sleep and health markers
Study acronymConvoy
Study objectivesTo determine the biological and neurobehavioural consequences of sleep disruption caused by railway vibration and noise, including cardiometabolic and cognitive function.
Ethics approval(s)

Approved 09/12/2025, Ethics Review Authority (Etikprovningsmyndigheten) (Box 2110, Uppsala, 75002, Sweden; +44 010-475 08 00; registrar@etikprovning.se), ref: 2025-07915-01

Health condition(s) or problem(s) studiedCombined effects of railway noise and vibration on sleep, biomarkers of cardiometabolic function and cognitive performance in healthy adults.
InterventionThe study is a prospective, within-subject cross-over trial conducted in the Sleep and Environmental Laboratory. Participants complete five consecutive overnight laboratory sessions, including a habituation night, a control night, and three intervention nights. The habituation night familiarises participants with the laboratory environment and study procedures and is excluded from outcome analyses.

During the control night, participants sleep without exposure to railway noise or vibration, providing a baseline for sleep, cardiometabolic, cognitive, and affective outcomes. During the three intervention nights, participants are exposed to simulated railway freight noise and vibration at urban levels . Each night includes 36 train events randomly distributed across an 8-hour sleep opportunity. In these three intervention nights (Night A, Night B and Night C), the levels of the railway noise and vibration are presented in different combinations (e.g. high vibration and low noise) to allow assessment of their individual and combined effects. The maximum vibration is 0.9 mm/s (with Swedish comfort weighting) and the maximum noise is 55 dB LAF,max.

All conditions are administered overnight in assigned bedrooms (23:00–07:00). Physiological sleep is monitored continuously using ambulatory polysomnography (PSG), and cardiac activity is recorded using electrocardiography (ECG) and finger photoplethysmography (PPG). No pharmacological treatments are administered.

The order of control and intervention nights is randomised using a Latin square design, with participants acting as their own controls. Daytime sleep is prohibited and monitored using wrist actigraphy. Caffeine intake is restricted after 15:00, and alcohol is prohibited. Participants consume consistent evening meals, recorded in food diaries. Screen time is monitored using the “Screen Time and Sleep” app throughout the pre-laboratory and laboratory periods.

Additional assessments include morning blood samples for plasma metabolomics, insulin, and glucose, morning and evening computerized cognitive testing, and questionnaires assessing baseline health, sleep, noise sensitivity, daily sleepiness, mood, and noise-induced disturbance.
Intervention typeBehavioural
Primary outcome measure(s)
  1. Fasting insulin resistance measured using the Homeostatic Model of Insulin Resistance (HOMA‑IR), which incorporates insulin concentrations measured by a Chemiluminescent Microparticle Immunoassay (CMIA) and blood glucose levels quantified using an enzymatic hexokinase/G‑6‑PDH method at morning immediately after the exposure to control night
  2. Fasting insulin resistance measured using the Homeostatic Model of Insulin Resistance (HOMA‑IR), which incorporates insulin concentrations measured by a Chemiluminescent Microparticle Immunoassay (CMIA) and blood glucose levels quantified using an enzymatic hexokinase/G‑6‑PDH method at morning immediately after the exposure to intervention night C
  3. Fasting insulin resistance measured using the Homeostatic Model of Insulin Resistance (HOMA‑IR), which incorporates insulin concentrations measured by a Chemiluminescent Microparticle Immunoassay (CMIA) and blood glucose levels quantified using an enzymatic hexokinase/G‑6‑PDH method at morning immediately after the the exposure to intervention night B
  4. Fasting insulin resistance measured using the Homeostatic Model of Insulin Resistance (HOMA‑IR), which incorporates insulin concentrations measured by a Chemiluminescent Microparticle Immunoassay (CMIA) and blood glucose levels quantified using an enzymatic hexokinase/G‑6‑PDH method at morning immediately after intervention night A
  5. Total sleep time measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  6. Total sleep time measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  7. Total sleep time measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  8. Total sleep time measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  9. Total amount of N1 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  10. Total amount of N2 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  11. Total amount of N3 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  12. Total amount of rapid eye movement (REM) sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  13. Total amount of rapid eye movement (REM) sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  14. Total amount of rapid eye movement (REM) sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  15. Total amount of rapid eye movement (REM) sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  16. Total amount of N1 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  17. Total amount of N1 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  18. Total amount of N1 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  19. Total amount of N2 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  20. Total amount of N2 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  21. Total amount of N2 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  22. Total amount of N3 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  23. Total amount of N3 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  24. Total amount of N3 sleep measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  25. Wakefulness after sleep onset (WASO) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  26. Wakefulness after sleep onset (WASO) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  27. Wakefulness after sleep onset (WASO) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  28. Wakefulness after sleep onset (WASO) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  29. Number of awakenings measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  30. Number of awakenings measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  31. Number of awakenings measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  32. Number of awakenings measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  33. Sleep onset latency (SOL) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control Night
  34. Sleep onset latency (SOL) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  35. Sleep onset latency (SOL) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  36. Sleep onset latency (SOL) measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  37. Sleep efficiency measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to control night
  38. Sleep efficiency measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night C
  39. Sleep efficiency measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night A
  40. Sleep efficiency measured using polysomnography/EEG, scored according to American Academy of Sleep Medicine guidelines at exposure to intervention night B
  41. Sleep depth assessed using the odds ratio product (ORP) measured using polysomnography/EEG measurements at exposure to control night
  42. Sleep depth assessed using the odds ratio product (ORP) measured using polysomnography/EEG measurements at exposure to intervention night B
  43. Sleep depth assessed using the odds ratio product (ORP) measured using polysomnography/EEG measurements at exposure to intervention night C
  44. Sleep depth assessed using the odds ratio product (ORP) measured using polysomnography/EEG measurements at exposure to intervention night A
  45. Maximal change of odds ratio product (ORP) measured using polysomnography/EEG measurements at exposure to railway vibration and noise events
  46. Area under the curve of odds ratio product (ORP) measured using polysomnography/EEG measurements and the trapezoid rule at exposure to railway vibration and noise events.
  47. N-acetylglucosamine/galactosamine (GlycA) concentration measured using NMR analysis of blood plasma at morning after exposure to control night
  48. N-acetylglucosamine/galactosamine (GlycA) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  49. N-acetylglucosamine/galactosamine (GlycA) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  50. N-acetylglucosamine/galactosamine (GlycA) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  51. Sialic acid (GlycB) concentration measured using NMR analysis of blood plasma at morning after exposure to control night
  52. Sialic acid (GlycB) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  53. Sialic acid (GlycB) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  54. Sialic acid (GlycB) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  55. Supramolecular phospholipid composite (SPC) concentration measured using NMR analysis of blood plasma at morning after exposure to control night
  56. Supramolecular phospholipid composite (SPC) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  57. Supramolecular phospholipid composite (SPC) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  58. Supramolecular phospholipid composite (SPC) concentration measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  59. Ethanol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  60. Ethanol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  61. Ethanol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  62. Ethanol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  63. Trimethylamine-N-oxide concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  64. Trimethylamine-N-oxide concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  65. Trimethylamine-N-oxide concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  66. Trimethylamine-N-oxide concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  67. 2-Aminobutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  68. 2-Aminobutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  69. 2-Aminobutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  70. 2-Aminobutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  71. Alanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after after exposure to control night
  72. Alanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  73. Alanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  74. Alanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  75. Asparagine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  76. Asparagine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  77. Asparagine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  78. Asparagine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  79. Creatine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  80. Creatine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  81. Creatine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  82. Creatine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  83. Glutamic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after after exposure to control night
  84. Glutamic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  85. Glutamic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  86. Glutamic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  87. Creatinine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  88. Creatinine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  89. Creatinine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  90. Creatinine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  91. Glycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  92. Glycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  93. Glycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  94. Glycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  95. Histidine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  96. Histidine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  97. Histidine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  98. Histidine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  99. Isoleucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  100. Isoleucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  101. Isoleucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  102. Isoleucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  103. Leucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  104. Leucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  105. Leucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  106. Leucine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  107. Lysine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  108. Lysine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  109. Lysine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  110. Lysine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  111. Methionine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  112. Methionine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  113. Methionine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  114. Methionine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  115. N,N-Dimethylglycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  116. N,N-Dimethylglycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  117. N,N-Dimethylglycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  118. N,N-Dimethylglycine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  119. Ornithine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  120. Ornithine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  121. Ornithine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  122. Ornithine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  123. Phenylalanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  124. Phenylalanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  125. Phenylalanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  126. Phenylalanine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  127. Proline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  128. Proline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  129. Proline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  130. Proline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  131. Sarcosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  132. Sarcosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  133. Sarcosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  134. Sarcosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  135. Threonine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  136. Threonine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  137. Threonine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  138. Threonine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  139. Tyrosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  140. Tyrosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  141. Tyrosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  142. Tyrosine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  143. Valine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  144. Valine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  145. Valine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  146. Valine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  147. 2-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  148. 2-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  149. 2-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  150. 2-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  151. Acetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  152. Acetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  153. Acetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  154. Acetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  155. Citric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  156. Citric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  157. Citric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  158. Citric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  159. Formic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  160. Formic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  161. Formic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  162. Formic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  163. Lactic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  164. Lactic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  165. Lactic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  166. Lactic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  167. Succinic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  168. Succinic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  169. Succinic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  170. Succinic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  171. Choline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  172. Choline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  173. Choline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  174. Choline concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  175. 2-Oxoglutaric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  176. 2-Oxoglutaric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  177. 2-Oxoglutaric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  178. 2-Oxoglutaric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  179. 3-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control night
  180. 3-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  181. 3-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  182. 3-Hydroxybutyric acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  183. Acetoacetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  184. Acetoacetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  185. Acetoacetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  186. Acetoacetic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  187. Acetone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  188. Acetone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  189. Acetone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  190. Acetone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  191. Pyruvic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  192. Pyruvic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  193. Pyruvic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  194. Pyruvic acid concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  195. D-Galactose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  196. D-Galactose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  197. D-Galactose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  198. D-Galactose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  199. Glucose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  200. Glucose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  201. Glucose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  202. Glucose concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  203. Glycerol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  204. Glycerol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  205. Glycerol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  206. Glycerol concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  207. Dimethylsulfone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to Control night
  208. Dimethylsulfone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  209. Dimethylsulfone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  210. Dimethylsulfone concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  211. Morning subjective sleepiness measured using Karolinska Sleepiness Scale at morning after exposure to control
  212. Morning subjective sleepiness measured using Karolinska Sleepiness Scale at morning after exposure to intervention night C
  213. Morning subjective sleepiness measured using Karolinska Sleepiness Scale at morning after exposure to intervention night B
  214. Morning subjective sleepiness measured using the Karolinska Sleepiness Scale at morning after exposure to intervention night A
  215. Self-reported sleep disturbance measured using on a 0-10 numerical scale, from "Not at all" to "Extremely" at morning after exposure to control
  216. Self-reported sleep disturbance measured using on a 0-10 numerical scale, from "Not at all" to "Extremely" at morning after exposure to intervention night A
  217. Self-reported sleep disturbance measured using on a 0-10 numerical scale, from "Not at all" to "Extremely" at morning after exposure to intervention night B
  218. Self-reported sleep disturbance measured using on a 0-10 numerical scale, from "Not at all" to "Extremely" at morning after exposure to intervention night C
  219. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to control
  220. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to intervention night C
  221. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to intervention night B
  222. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to intervention night A
  223. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to control
  224. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to intervention night A
  225. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to intervention night B
  226. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at morning after exposure to intervention night C
  227. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to control
  228. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to intervention night C
  229. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to intervention night B
  230. Negative affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to intervention night A
  231. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to control
  232. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to intervention night A
  233. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to intervention night B
  234. Positive affect measured using using the Positive and Negative Affect Schedule (PANAS) at Evening after exposure to intervention night C
  235. Glutamine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to control
  236. Glutamine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  237. Glutamine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  238. Glutamine concentration (mmol/L) measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  239. Glyc/SPC, a ratio comparing the inflammatory glycoprotein signal (Glyc) to the phospholipid‑related signal (SPC), measured using NMR analysis of blood plasma at morning after exposure to control
  240. Glyc/SPC, a ratio comparing the inflammatory glycoprotein signal (Glyc) to the phospholipid‑related signal (SPC), measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  241. Glyc/SPC, a ratio comparing the inflammatory glycoprotein signal (Glyc) to the phospholipid‑related signal (SPC), measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  242. Glyc/SPC, a ratio comparing the inflammatory glycoprotein signal (Glyc) to the phospholipid‑related signal (SPC), measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  243. Glyc measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  244. Glyc measured using NMR analysis of blood plasma at morning after exposure to control
  245. Glyc measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  246. Glyc measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  247. Calcium disodium EDTA (CaEDTA) measured using NMR analysis of blood plasma at morning after exposure to control
  248. CaEDTA measured using NMR analysis of blood plasma at morning after exposure to intervention night B
  249. CaEDTA measured using NMR analysis of blood plasma at morning after exposure to intervention night C
  250. CaEDTA measured using NMR analysis of blood plasma at morning after exposure to intervention night A
  251. Insulin concentration measured using a Chemiluminescent Microparticle Immunoassay (CMIA) analysis of blood samples at morning after morning after exposure to control
  252. Insulin concentration measured using a Chemiluminescent Microparticle Immunoassay (CMIA) analysis of blood samples at morning after exposure to intervention night A
  253. Insulin concentration measured using a Chemiluminescent Microparticle Immunoassay (CMIA) analysis of blood samples at morning after exposure to intervention night B
  254. Insulin concentration measured using a Chemiluminescent Microparticle Immunoassay (CMIA) analysis of blood samples at morning after exposure to intervention night C
Key secondary outcome measure(s)
  1. Subjective sleepiness measured using the Karolinska Sleepiness Scale at evening after exposure to control
  2. Subjective sleepiness measured using the Karolinska Sleepiness Scale at evening after after exposure to intervention night C
  3. Subjective sleepiness measured using Karolinska Sleepiness Scale at evening after after exposure to intervention night B
  4. Subjective sleepiness measured using Karolinska Sleepiness Scale at evening after after exposure to intervention night A
  5. Cardiovascular activation in response to noise and vibration measured using change in heart rate (ECG) at occurring within the time window of each discrete railway event, during the control and each of the three intervention nights (23:00 to 07:00)
  6. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to control
  7. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to intervention night C
  8. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to intervention night B
  9. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to intervention night A
  10. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to control
  11. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to intervention night A
  12. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to intervention night B
  13. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at evening after exposure to intervention night C
  14. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to intervention night C
  15. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to intervention night B
  16. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to intervention night A
  17. Neurobehavioural speed measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to control
  18. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to control
  19. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to intervention night A
  20. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to intervention night B
  21. Neurobehavioural accuracy measured using 10 cognitive tests (motor praxis, visual object learning, fractal 2-back, abstract matching, line orientation, emotion recognition, matrix reasoning, digit symbol substitution, balloon analog risk, psychomotor vigilance) at morning after exposure to intervention night C
Completion date12/06/2026

Eligibility

Participant type(s)
Age groupAdult
Lower age limit18 Years
Upper age limit30 Years
SexAll
Target sample size at registration24
Key inclusion criteria1. Live in or around the city of Gothenburg area (Sweden)
Key exclusion criteria1. Age below 18 or above 30 years.
2. Usual weekday sleep and wake times that differ by more than ±1 hour from the study schedule (i.e., usual bedtime outside
22:00–00:00 or usual wake time outside 06:00–08:00), as confirmed by one week of actigraphy.
3. Body mass index (BMI) greater than 25 kg/m².
4. Regular use of sleep medication (prescribed or over-the-counter).
5. Hearing loss as measured during screening via pure tone audiometry.
6. Diagnosed sleep disorders.
7. High risk for sleep apnea based on the STOP-BANG questionnaire.
8. Engagement in shift work.
9. Use of tobacco, vaping, snus, or other nicotine products.
10. Pregnancy or breastfeeding.
Date of first enrolment22/02/2026
Date of final enrolment25/05/2026

Locations

Countries of recruitment

  • Sweden

Study participating centre

University of Gothenburg
Guldhedsgatan 5A
Gothenburg
41320
Sweden

Results and Publications

Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot expected to be made available
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Protocol file 28/01/2026 No No
Statistical Analysis Plan 28/01/2026 No No

Additional files

48899_Protocol_SAP.pdf
Protocol file
48899_Protocol_SAP.pdf
Statistical Analysis Plan

Editorial Notes

27/01/2026: Study’s existence confirmed by the Ethics Review Authority (Etikprovningsmyndigheten), Sweden.

BMC - Part of Springer Nature Springer Nature