Older Adults Exercising On Time
Phase: NA
Conditions: Insomnia, Circadian Rhythm Disorders
Sponsor: Leiden University Medical Center

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Ouderen op tijd in beweging studie 
Older adults exercising on time 
(February 2024) 
 
 
 
 

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PROTOCOL TITLE ‘Older adults exercising on time.’ 
 
Protocol ID 
Not applicable 
Short title 
ON TIME study (OP TIJD studie) 
EudraCT number  
   
Version 
Version 8 
Date 
February 2024 
Coordinating investigator/project 
leader 
 
 
 
 
 
 
 
 
 
Principal investigator (in Dutch: 
hoofdonderzoeker/ uitvoerder) 
 
 
 
 
 
 
 
 
 
Sponsor (in Dutch: 
verrichter/opdrachtgever) 
Leiden University Medical Center 
Subsidising party 
Nederlandse Organisatie voor Wetenschappelijk 
Onderzoek (NWO) 
Independent expert 
 
 
 
 
 
 
  
 
Laboratory sites 
 
 
 
 

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Pharmacy  
Not applicable 

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TABLE OF CONTENTS 
 
1. 
INTRODUCTION AND RATIONALE .............................................................................11 
2. 
OBJECTIVES ................................................................................................................13 
3. 
STUDY DESIGN ...........................................................................................................14 
3.1 
Design justification .................................................................................................15 
4. 
STUDY POPULATION ..................................................................................................16 
4.1 
Population (base) ...................................................................................................16 
4.2 
Inclusion criteria .....................................................................................................16 
4.3 
Exclusion criteria ....................................................................................................16 
4.4 
Sample size calculation ..........................................................................................17 
5. 
TREATMENT OF SUBJECTS .......................................................................................19 
5.1 
Investigational treatment ........................................................................................19 
5.1.1 
Active morning and active evening intervention ...............................................19 
5.1.1 
Sedentary period .............................................................................................20 
5.2 
Use of co-intervention ............................................................................................20 
6. 
INVESTIGATIONAL PRODUCT ....................................................................................21 
7. 
NON-INVESTIGATIONAL PRODUCT ...........................................................................22 
7.1 
Name and description of non-investigational product(s) .........................................22 
8. 
METHODS ....................................................................................................................23 
8.1 
Study parameters/endpoints ...................................................................................23 
8.1.1 
Main study parameter/endpoint .......................................................................23 
8.1.2 
Secondary study parameters/endpoints ..........................................................23 
8.1.3 
Other study parameters ...................................................................................24 
8.2 
Randomisation, blinding and treatment allocation ..................................................25 
8.3 
Study procedures ...................................................................................................25 
8.3.1 
Questionnaires ................................................................................................26 
8.3.2 
Mental health investigations ............................................................................27 
8.3.3 
Clinical test/procedures ...................................................................................28 
8.3.4 
Invasive procedures ........................................................................................30 
8.4 
Withdrawal of individual subjects ............................................................................31 
8.4.1 
Specific criteria for withdrawal (if applicable) ...................................................31 
8.5 
Replacement of individual subjects after withdrawal ...............................................32 
8.6 
Follow-up of subjects withdrawn from treatment .....................................................32 
8.7 
Premature termination of the study .........................................................................32 
9. 
SAFETY REPORTING ..................................................................................................33 
9.1 
Temporary halt for reasons of subject safety ..........................................................33 
9.2 
AEs, SAEs and SUSARs ........................................................................................33 
9.2.1 
Adverse events (AEs) ......................................................................................33 
9.2.2 
Serious adverse events (SAEs) .......................................................................33 
9.2.3 
Suspected unexpected serious adverse reactions (SUSARs) .........................33 
9.3 
Annual safety report ...............................................................................................34 
9.4 
Follow-up of adverse events ...................................................................................34 

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9.5 
Data Safety Monitoring Board (DSMB) ...................................................................34 
10. 
STATISTICAL ANALYSIS ..........................................................................................35 
10.1 
Primary study parameter ........................................................................................35 
10.2 
Secondary study parameter(s) ...............................................................................35 
10.3 
Other study parameters ..........................................................................................36 
10.4 
Interim analysis ......................................................................................................36 
11. 
ETHICAL CONSIDERATIONS ...................................................................................37 
11.1 
Regulation statement .............................................................................................37 
11.2 
Recruitment and consent........................................................................................37 
11.3 
Objection by minors or incapacitated subjects (if applicable) ..................................37 
11.4 
Benefits and risks assessment, group relatedness .................................................37 
11.5 
Compensation for injury .........................................................................................38 
11.6 
Incentives (if applicable) .........................................................................................38 
12. 
ADMINISTRATIVE ASPECTS, MONITORING AND PUBLICATION .........................38 
12.1 
Handling and storage of data and documents ........................................................38 
12.2 
Monitoring and Quality Assurance ..........................................................................39 
12.3 
Amendments ..........................................................................................................39 
12.4 
Annual progress report ...........................................................................................39 
12.5 
Temporary halt and (prematurely) end of study report ............................................39 
12.6 
Public disclosure and publication policy ..................................................................40 
journals and (inter)national conferences, according to the CCMO statement of publication 
policy. An overview of general results will also be communicated to the participants via 
newsletters. In accordance to the ICMJ guidelines, parties that have contributed 
significantly to the study, will be included as co-authors in publications when applicable. .40 
13. 
STRUCTURED RISK ANALYSIS...............................................................................41 
14. 
REFERENCES ..........................................................................................................42 
15. 
Appendix ....................................................................................................................45 
15.1 
Appendix A .............................................................................................................45 
15.2 
Appendix B .............................................................................................................46 

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LIST OF ABBREVIATIONS AND RELEVANT DEFINITIONS  
 
ABR 
General Assessment and Registration form (ABR form), the 
application form that is required for submission to the accredited 
Ethics Committee; in Dutch: Algemeen Beoordelings- en 
Registratieformulier (ABR-formulier) 
ADL 
Activities of daily living 
AE 
Adverse Event 
AET 
Aerobic Endurance Training  
AR 
Adverse Reaction 
BIA 
Bioelectrical Impedance Analysis 
CA 
Competent Authority 
CBT 
Core Body Temperature 
CCI 
Charlson comorbidity index 
CCMO 
Central Committee on Research Involving Human Subjects; in 
Dutch: Centrale Commissie Mensgebonden Onderzoek 
CFS 
Clinical frailty scale 
Chronoactivity Timing of physical activity 
CV 
Curriculum Vitae 
CVD 
Cardiovascular Disease 
DLMO 
Dim Light Melatonin Onset 
DSMB 
Data Safety Monitoring Board 
ECG 
Electrocardiogram 
EMA 
Ecological Momentary Assessment 
EU 
European Union 
EudraCT 
European drug regulatory affairs Clinical Trials  
EQ-VAS 
EuroQol visual analogue scale 
GCP 
Good Clinical Practice 
GDPR 
General Data Protection Regulation; in Dutch: Algemene 
Verordening Gegevensbescherming (AVG) 
G8 
Geriatric-8 
HR 
Heart Rate 
HRV 
Heart rate variability 
IADL 
Instrumental activities of daily living 
IB 
Investigator’s Brochure 
IC 
Informed Consent 
IMP 
Investigational Medicinal Product  

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IMPD 
IMD 
IMDD 
Investigational Medicinal Product Dossier  
Investigation with Medical Device 
Investigational Medical Device Dossier 
ISI 
Insomnia Severity Index 
IQR 
Interquartile Range 
METC  
Medical research ethics committee (MREC); in Dutch: medisch-
ethische toetsingscommissie (METC) 
LUMC 
Leiden University Medical Center 
MCTQ 
Munich Chronotype Questionnaire 
MET 
Metabolic Equivalent of a Task 
Mg 
Miligravity 
MRI 
Magnetic Resonance Imaging 
PAI 
Physical Activity Index 
PBMC 
Peripheral Blood Mononuclear Cell 
PPG 
Photoplethysmography 
QOL 
Quality Of Life 
RET 
Resistance Exercise Training 
(S)AE 
(Serious) Adverse Event  
SCN 
Suprachiasmatic Nucleus 
SD 
Standard Deviation 
SPC 
Summary of Product Characteristics; in Dutch: officiële 
productinformatie IB1-tekst 
Sponsor 
The sponsor is the party that commissions the organisation or 
performance of the research, for example a pharmaceutical 
company, academic hospital, scientific organisation or 
investigator. A party that provides funding for a study but does not 
commission it is not regarded as the sponsor, but referred to as a 
subsidising party. 
SUSAR  
Suspected Unexpected Serious Adverse Reaction 
SQUASH 
Short Questionnaire to Assess Health enhancing Physical Activity 
UAVG 
Dutch Act on Implementation of the General Data Protection 
Regulation; in Dutch: Uitvoeringswet AVG 
WMO 
Medical Research Involving Human Subjects Act; in Dutch: Wet 
Medisch-wetenschappelijk Onderzoek met Mensen 
 
 

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SUMMARY 
 
Rationale: There are indications based on epidemiological cohort studies and animal 
experiments that timing of physical activity (also referred as “chronoactivity”), irrespective of 
intensity, impacts health status and disease risk. Here, we hypothesize that timing of physical 
activity has a beneficial impact on insomnia symptoms and related circadian health parameters 
(e.g., metabolic, psychosocial) in older people.  
Objective: Main: To examine the effect of physical activity timing on insomnia severity in older 
adults with self-reported sleep problems. 
Additional: To examine the effect of physical activity timing on exploratory rhythmic parameters 
of biological clock function, physiology and metabolism, mental health, behavioural factors, 
and immune and cell signalling functions. 
Study design: Randomised cross-over study. 
Study population: 40 community dwelling older adults aged between 60 and 80 years old 
with long-lasting (≥3 months) self-reported sleep problems from Leiden and surrounding areas 
in close proximity to the study center. 
Intervention: The intervention will comprise one sedentary period and two periods of 
increased physical activity with different daily patterns: 1) active morning; 2) active evening; 
with a duration of 14 days each. In both active intervention arms, participants will follow 8 
coached outdoor physical exercise sessions (Vitality Club) comprising endurance and strength 
exercises. The training sessions will be held first either in the morning or evening (depending 
on the intervention arm) and will be one hour long. On days participants are not able to attend 
the Vitality Club, they will be asked to follow the ‘Active@Home’ program; a 1-hour training 
session of various moderate to vigorous activities. Since this will be a randomized cross-over 
study, all participants will follow the sedentary period as well as both exercise timing 
interventions consecutively with a 7-day wash-out period between all interventions. 
Main study parameters/endpoints: The primary outcome is change in insomnia severity as 
measured by the Insomnia Severity Index (ISI). Secondary outcomes parameters include 
multiple components of objective sleep quality measured with the Withings Sleep Analyzer, tri-
axial accelerometry and subjective sleep quality questions as well as circadian and diurnal 
patterns of melatonin, heart rate, heart rate variability, breathing rate, oxygen saturation, core 
body temperature, EMA, and objective emotional arousal and stress. Additionally, we will 
observe eating patterns (timing and overall intake). Finally, blood will be sampled at baseline 
and after each intervention and stored for measurements of metabolic and physiological 
functioning and expression of genes involved in the regulation of the biological clock. 
Nature and extent of the burden and risks associated with participation, benefit and 
group relatedness: Blood sampling, explanation of use of the measurement devices and the 

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assessment of participants well-being will be done by a trained nurse at the LUMC and at home 
to minimize burden for participants. During the complete study duration, participants will wear 
one wrist-worn wearable that is capable of measuring multiple physiological aspects in the 
participant. Moreover, participants are asked to perform three series of seven consecutive 
saliva swabs on set times on the last day of each intervention and they will be asked to rank 
their mood as well as log their meals multiple times a day. The risks of this study are considered 
minimal since this is a lifestyle intervention and only minimally invasive procedures are used 
(venous blood sample which may cause a small hematoma) that can be considered routine 
medical practice and are known to carry only minimal risks. The study may cause some burden 
since participants are required to change and monitor their daily routine for a longer period (42 
non-consecutive days) of time. 
 
 
 

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1. INTRODUCTION AND RATIONALE 
 
Essentially all biochemical, physiological and behavioural processes are orchestrated by 
circadian rhythms to respond to the 24-hour day/night cycle. Processes such as energy 
metabolism, hormone levels, sleep wake cycles, core body temperature are strongly governed 
by circadian rhythms.(1) Proper functioning according to the light/dark cycle of all bodily 
functions relies on the suprachiasmatic nucleus (SCN) also known as the central clock which 
is located directly behind the eyes in the anterior hypothalamus and primarily responds to 
light.(1) The SCN determines the phase of peripheral clocks through a variety of signalling 
relays.(2)  
A good running circadian clock is associated with (healthy) longevity.(3) Yet, proper 
circadian organization (also referred as “circadian health”)(4) is threatened by our modern day 
24-hour society. Shift work, social jetlag, increased exposure to blue-light emitting devices and 
globalization of a 24/7 society facilitated by advancing technology and social media, jeopardize 
a healthy biological rhythm.(4) 
When internal circadian rhythms, which are normally approximately 24-hour cycles, are 
not synchronised with the environment or each other, disruption of circadian and diurnal 
rhythms can occur.(5) This ‘desynchrony’ occurs when behaviours such as physical activity, 
sleep, food intake, and exposure to light are not at an appropriate time relative to the central 
circadian clock.(5) Another cause of circadian misalignment or desynchrony is ageing. A 
substantial amount of studies shows the deterioration of the biological clock with increasing 
age (Figure 1).(1, 3, 6) Studies consistently show that experimental disruption or 
desynchronisation of circadian rhythms has detrimental effects on health and lifespan.(7, 8) 
Our decreasing circadian health may be partly responsible for the rising prevalence of sleep 
problems in (older) adults. In the Netherlands, 20% of all people of 12 years and older have 
self-reported sleep problems and even 28% of older adults aged 75 years and older.(9) 
Additionally, and perhaps through the pathway of poor sleep, clear associations of circadian 
misalignment are observed with cancer 
onset, cardiometabolic diseases such 
as obesity, diabetes, heart disease, 
and stroke, and neurologic disease 
such 
as 
depression, 
Parkinson 
disease, 
dementia, 
and 
sleep 
disorders.(4, 5, 10, 11) 
‘Zeitgebers’, which are defined 
as regular cyclic environmental signals 
and which include food intake, light 
Figure 1. Effect of ageing on circadian rhythms (Liu et al.)(1) 

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exposure, and physical activity, can calibrate our circadian clock.(12, 13) Regular physical 
activity is known to positively affect the circadian clock and is associated with healthy 
ageing.(13, 14) Guidelines indicate the required intensity, frequency and duration of physical 
activity to maintain or achieve health. However, less is known about the best timing of physical 
activity. A growing field of research on ‘chronobehaviour’, (timing of lifestyle behaviours) 
already marks the importance of timing of food intake and light exposure.(4, 15-21) Yet, 
intervention studies on ‘chronoactivity’ (timing of physical activity) are largely lacking. Ideally, 
enriching current guidelines by adding the timing component of physical activity might improve 
these guidelines and facilitate for more effective physical activity and faster improvement of 
health outcomes such as recovering from a period of worse sleep. 
Several studies in mice reported that exercise restores circadian heart rate and body 
temperature in mice with central circadian disruption.(22, 23) Additionally, studies in humans 
have revealed exercise stimulates the expression of core clock genes. Observational studies 
that specifically focussed on chronoactivity, demonstrate associations between morning 
physical activity and increased metabolic health,(24) increased cardiometabolic fitness,(25) 
and even an approximately 15% lower risk of incident atherosclerotic cardiovascular and 
cerebrovascular disease(26). Moreover, there are some intervention studies in this field.(27-
29) However, their results are inconclusive. Multiple studies show the seemingly positive effect 
of morning physical activity on body composition and metabolic health.(29, 30) Contrarily, 
several studies  show opposite findings indicating that evening exercise had positive effects 
on heart rate recovery, blood pressure, and blood glucose levels.(27, 28, 31). One of these 
even stated that morning physical activity had a deleterious effect on blood glucose levels in 
diabetic men.(27) This contrariety in existing literature could be partly explained by 1) different 
study outcomes, 2) different measurement methods and definitions of physical activity, and 3) 
small sample sizes and specific groups (e.g., diabetic men or menopausal women) in which 
the studies have been conducted. Nevertheless, these studies suggest that timing of physical 
activity serves as an important Zeitgeber, and changes the phase of the molecular clock, 
specifically in peripheral tissues.(22) Yet, despite the increasing interest and mounting 
evidence for chronoactivity, the optimal circadian timing of physical activity for circadian health 
remains unclear and little is known about the influence of chronoactivity in older adults which 
most frequently suffer from sleep problems.(9) 
In view of the detrimental effects of circadian misalignment, the large group of older 
people suffering from sleep problems, and the seeming importance of chronoactivity, we will 
perform a randomised cross-over study that aims to uncover the effect of timing of physical 
activity on insomnia severity and related (circadian) health parameters in older adults with self-
reported sleep problems. 

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2. OBJECTIVES 
 
Primary Objective  
To examine the effect of physical activity timing on insomnia severity in older adults with self-
reported sleep problems. 
 
Secondary Objective 
To explore the effect of physical activity timing on rhythmic parameters of biological clock 
function, physiology and metabolism, mental health, behavioural factors, and immune and 
cell signalling functions. 
 
 

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3. STUDY DESIGN 
 
We will perform a randomized two-armed cross-over study. Both groups will start with the 
sedentary period. Randomization will be performed at the moment of enrollment using a 
computer-based statistical program (depending on the intervention arm, participants will then 
undergo the active morning intervention or active evening intervention first, followed by the 
remaining intervention. There will be a total of two washout periods both lasting 7 days, one 
between the sedentary period and first intervention and one between the first and second 
intervention to prevent or minimize ‘carry over’ of previous intervention effect. The two 
interventions and the sedentary period will last 14 days each and contain a ‘calibration period’ 
(7 days) and a ‘measurement week’ (7 days). The former will serve as an adjustment period in 
which we hypothesize that our endpoints of interest will adjust to the new exercise regimen. 
After the calibration period, the measurement week starts in which all endpoints will be 
measured. Apart from the measurements, there are no differences in intervention between 
calibration and measurement week. The total study duration will be 8 weeks and the study will 
largely take place at the participants’ home except for the training sessions (Vitality Clubs) that 
will take place at an outdoor sports facility in the municipality of Leiden and the study site visits 
which will take place in the LUMC. Figure 3.1 shows a schematic overview of the study outline 
and Appendix A shows an example of the study schedule during the active morning 
intervention. 
 
 
 
Figure 3.1. Schematic overview of the study 

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3.1 Design justification 
A cross-over study allows the response of a participant to morning exercise to be contrasted 
with the same participant’s response to evening physical activity and sedentary period. 
Removing inter-participant variation allows for more efficient and precise estimation than 
similar sized studies with parallel intervention groups.  
As we study the effect of timing on change in insomnia severity and changes in the rhythm of 
multiple processes hypothesized to be altered rapidly through environmental cues, such as 
daylight changes over the season, a randomized cross-over study which is usually bound to 
short-term outcomes is the most suitable design for this study. 
 
 

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4. STUDY POPULATION 
4.1 Population (base)  
Dutch speaking older adults between 60 and 80 years old (male and female) from the general 
population in the Netherlands will be selected as participants for this study. Individuals who 
are interested in participating in the study based on the advertisements, will be screened by 
phone. During the first phone call questions will be asked about (i) personal data, (ii)  presence 
of sleep problems, and (iii) availability during the study period via a screenings questionnaire. 
If the person seems eligible based on their answers to these questions, a PIF and IC will be 
sent to them by mail. A second phone call will be scheduled at least one week after the first 
phone call to address any questions related to the PIF. After receipt of verbal consent, during 
the second phone call, a screening at the study center will be planned. During the screening 
visit, which will take approximately 30 minutes, participants can give written informed consent. 
Thereafter, two non-fasted blood samples will be drawn (3.5 ml + 2 ml =5.5 ml), and two 
questionnaires will be filled out: (i) Insomnia Severity Index (ISI, to assess insomnia symptoms) 
and (ii) Munich chronotype Questionnaire (MCTQ, to assess chronotype). The latter will not be 
used as a screeningstool but is collected as a baseline characteristic. We will include 
participants scoring ≥10 on the ISI. Additionally, we believe that the possible outcomes of this 
study will be relevant for older adults with sleep problems since both ageing as well as sleep 
problems are closely linked to the circadian clock. Potential participants will be recruited 
through advertisements in newspapers and local radio. For practical reasons and since the 
‘Vitality Clubs’ are located here, participants will be sought in Leiden and surroundings.  
 
4.2 Inclusion criteria 
In order to be eligible to participate in this study, all participants must meet all of the 
following criteria: 
• 
Aged between 60 and 80 years old 
• 
Retired 
• 
Long lasting sleep problems (as assessed by a the screening questionnaire 
administered telephonically and by the ISI which will be filled out during the 
screening visit) 
• 
Access to and ability to use a smart phone (Android or Apple) 
 
4.3 Exclusion criteria 
A potential subject who meets any of the following criteria will be excluded from 
participation in this study: 

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• 
Currently employed or working  
• 
Participation in any sort of fasting regimen (e.g. intermitted fasting or Ramadan) 
• 
Experienced recent (<6 months) adverse life events (e.g., death of partner) 
• 
Abnormal values in glucose metabolism, thyroid, liver or kidney function, or 
inflammation markers that after examination of the study doctor need immediate 
attention of a general practitioner or specialist. 
• 
Diagnosed clinical depression 
• 
Diagnosed neurodegenerative diseases (e.g. dementia or Parkinson’s disease) 
• 
Diagnosed sleep apnoea 
• 
Diagnosed restless legs syndrome 
• 
Use of beta-adrenergic blocking agents 
• 
Use of sleep medication* 
• 
Injuries or other severe physical conditions (such as active arthrosis) that inhibits 
physical activity 
• 
Travelled across time zones one week prior to start of study 
 
*If participants are willing to cease usage of sleep medication 2 weeks before baseline 
measurement until the end of the study, they can be included. An exception must be made 
for individuals with amitriptyline prescribes as sleep medication due to its side effects of 
discontinuing use. 
For this study we want to use CTcue to facilitate the inclusion of patients.  
 
4.4 Sample size calculation 
The sample size was calculated for the primary outcome of mean change of insomnia 
symptoms severity from baseline and after completing the active morning vs. active evening 
measured by the ISI which is proven to be a well validated and sensitive questionnaire for 
mapping insomnia severity. All sample size calculations were based on statistical power of 
0.80 and a 2-sided α of 0.05. The calculations were performed using GPower v.3.1 (Kiel 
University, Germany). To the best of our knowledge, there is no literature available on the 
effect size of physical activity timing on insomnia severity. Therefore, estimations were based 
on treatment effect size of guideline recommended physical activity on insomnia severity 
(measured by ISI) found in a previous randomized controlled trial(32). Assuming a standard 
deviation (SD) of 5.4, a total of 36 participants are required to detect a minimal difference of 
2.6 points on the ISI. Considering a possible dropout rate of 10% during the study, the target 
sample size is 40 participants.   

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5. TREATMENT OF SUBJECTS 
 
5.1 Investigational treatment 
5.1.1 
Active morning and active evening intervention 
Participants will participate in three interventions consisting each of a 14-day physical 
activity regimen. The active morning and active evening intervention are equal in content 
but in the active morning group, participants will be instructed to be active between 10:00 
and 11:00 hour in the morning and the active evening will be instructed to be active between 
19:30 and 20:30 in the evening. Both groups will be instructed to refrain from any moderate 
to vigorous exercise for the rest of the day. Per intervention, a total of eight Vitality Club 
training session will be organised given by a trained sports coach or physical therapist 
specialized in geriatric physical therapy. These training sessions will be different in 
character (e.g., a game of volleyball and a circuit training) but will all contain a combination 
of strength and endurance training tailored for older adults. Literature is inconclusive 
whether it is more beneficial to participate in aerobic endurance training (AET) or resistance 
exercise training (RET). AET is more beneficial for body composition and endurance and 
RET is more beneficial for muscle mass and strength. Both types of exercises contribute to 
important components of QOL and healthy ageing and therefore we believe that it is most 
valuable/effective to compose a training regimen containing both AET and RET 
exercises.(34) During the weekends (Saturday and Sunday), there will not be a Vitality Club 
sessions. Instead, participants will be asked to perform a ‘relative rest’ session. On a 
‘relative rest’ day, participants will be given the opportunity to recover from the vitality club. 
Yet, since we do not want to lose the effect of the intervention, we ask the participants to 
perform any light activity during the given window of time of the intervention arm. For one 
weekend day (Saturday) in the measurement week, or when participants are unable to 
participate in the Vitality Club, they will be asked to perform some sort of physical 
activity/exercise at home (the ‘Active@Home’ program) between the above-mentioned 
times (depending on the intervention). Participants will be handed multiple training 
schedules/options for the Active@Home option corresponding to a metabolic equivalent of 
3-8 MET’s (moderate to vigorous physical activity) for one hour. Participants will also be 
asked to refrain from activities with equal MET’s for the rest of the day to ensure that their 
physical activity peak will only be in the morning or evening (depending on the intervention). 
To ensure participants will stay well informed, they will be handed a booklet with all 
necessary information and a day by day description of all measurements and exercise 
program (‘E4. Studieboekje’).  

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5.1.1 
Sedentary period 
Literature shows that physical activity improves insomnia severity.(32) In previous studies, 
the follow-up period was at least 3 months. As we will use a shorter follow-up period in this 
study, we have included a sedentary period, to assess the effect of physical activity versus 
no physical activity. This intervention additionally examines the effect of physical activity 
timing. In order to verify that the exercise intervention provided in this study has a similar 
positive effect, we will compare our interventions to this sedentary period. All participants 
will start with a 14-day sedentary period. They will be instructed to refrain from any moderate 
to vigorous exercise. Compliance to these instructions will be observed through the wrist 
worn accelerometer. Where necessary, participants will be reminded of the instructions.  
 
5.2 Use of co-intervention 
Not applicable 

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6. INVESTIGATIONAL PRODUCT  
Not applicable 
 

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7. NON-INVESTIGATIONAL PRODUCT 
 
7.1 Name and description of non-investigational product(s) 
All measurement devices used in this study were reviewed by the ‘medische technologie’ 
department of the LUMC and were used before in other studies in the LUMC. A statement 
from the ‘medische technologie’ can be found in the researchdossier (D4. ‘Verklaring 
meetinstrumenten medische technologie’). 
 
Table for measurement devices of outcome variables 
Name of device 
Manufacturer 
Model 
CE conform 93/42/EEG 
of 
EU/2017/745 (Medical 
devices) 
OR 
98/79/EEG of 
EU/2047/746 
(in-vitro diagnostics) 
Conform 
intended 
use as 
described 
in the 
instruction 
manual?  
Multifunctional 
wearable  
Corsano 
Cardiowatch 287-2  
Yes 
Yes 
Electronic 
Ecological 
momentary 
assessment tool 
M-path Leuven 
M-path app (*or 
similar platform) 
- 
Yes 
Sleep Analyzer 
Withings 
Sleep Analyzer 
No, conform 2014/53/EU 
Yes 
 
Table of measurement devices for baseline measurements 
Name of device 
Manufacturer 
Model 
CE conform 93/42/EEG 
of 
EU/2017/745 (Medical 
devices) 
OR 
98/79/EEG of 
EU/2047/746 
(in-vitro diagnostics) 
Conform 
intended 
use as 
described 
in the 
instruction 
manual?  
Bioelectrical 
impedance 
analyser 
Akern 
BIA ASE 101 
Yes 
Yes 
Blood pressure 
device 
Welch Allyn 
ProBP3400 (or similar 
device) 
Yes, conform 93-42/EEG 
Yes 
Dynamometer 
JAMAR 
Handdynamometer 
Hydraulic  
Yes 
Yes 

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8. METHODS 
8.1 Study parameters/endpoints 
8.1.1 Main study parameter/endpoint 
The main outcome of this study will be insomnia severity which will be measured by the Dutch 
version of the ISI ranging from 0-28 (0-7: no clinically significant insomnia; 8-14: subthreshold 
insomnia; 15-21: moderate severity clinical insomnia; 22-28: severe clinical insomnia).(35)  
 
8.1.2 Secondary study parameters/endpoints 
Secondary and exploratory endpoints include: 
Biological clock function  
• 
Clockgene expression 
• 
Core body temperature (°C) 
o Diurnal pattern 
o Time of lowest temperature 
• 
Melatonin 
o 
Dim light melatonin onset (DLMO) 
 
Physiological parameters 
• 
Heart rate 
o Diurnal pattern 
o Average 
o Resting heart rate 
o Minimum/peak heart rate (5 and 95 percentile) 
• 
Heart rate variability (HRV) 
• 
Breathing rate 
• 
Oxygen saturation (SpO2) 
 
Mental health 
• 
Subjective mood 
o Diurnal pattern of: 
▪ 
Positive affectivity 
▪ 
Negative affectivity 
▪ 
Energy 
▪ 
Fatigue  
▪ 
Cognition  
• 
(objective) Electrodermal activity (emotional arousal and stress) 
 
Behavioural factors 
• 
Food intake 
o Frequency  
o Timing  
• 
Habitual sleep (Table 8.1) 
o Sleep latency (min) 
o Duration (min) 
o Efficiency (%) 
o Sleep phases (%, min) 
o Awakenings at night (x, min) 

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o Objective physical activity through accelerometry (mg) 
o 4-meter walk test 
• 
Cardiometabolic measurements 
o Resting systolic and diastolic blood pressure 
o Standard biochemistry profile (e.g., glucose, HD, triglycerides) 
• 
Daily functioning  
o Katz activities for daily living (Katz-ADL) 
o Lawton Instrumental activities of daily living (IADL) 
• 
Quality of life 
o EuroQol five dimension questionnaire (EQ-5D-3L) 
o EuroQol visual analogue scale (EQ-VAS) 
• 
Comorbidities 
o Charlson comorbidity index (CCI) 
• 
Frailty 
o Clinical frailty scale (CFS) 
o Geriatric 8 (G-8) 
• 
Subjective sleep quality 
o Pittsburgh Sleep Quality Index (PSQI) 
o Sleep chronotypeMunich ChronoType Questionnaire (MCTQ) 
• 
Medication use  
• 
Medical history 
 
8.2 Randomisation, blinding and treatment allocation 
As this is a cross-over study, participants will undergo all three conditions. Participants 
will be randomised into two groups at enrolment using a computer-based statistical 
program. Both groups will start with sedentary period where after the first group will 
start with the active morning first followed by the active evening. For the second group, 
the order of the two activity interventions will be reversed (sedentary period- active 
evening- active morning). Blinding will not be possible in this study. However, we will 
minimise the interference of the researchers that will perform the analyses during the 
study by hiring a research nurse to lead the study. If necessary, the research nurse will 
be assisted by medical students. 
 
8.3 Study procedures 
Appendix A shows a snapshot of the study and a schematic overview of its 
procedures. Appendix B shows the frequency and estimated duration of all study 
procedures. The table distinguishes between active and passive procedures and in this 
way also indicates the burden of all procedures (passive procedure=less burdensome). 
For example, filling out the ecological momentary assessments is marked as active 
study procedures (more burdensome) while heart rate measurement is marked as a 
passive procedure (participants wearing the wrist-worn heart rate monitor).Intervention 
procedures 
 
Sedentary behaviour 

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During the sedentary period, participants are asked to attain their inactive/sedentary 
lifestyle. This means that they have to refrain from all moderate to vigorous (social) physical 
activities.  
 
Physical activity interventions 
During the active morning and active evening interventions, participants are expected to 
exercise on the set hour of the corresponding intervention. Chapter 5.1.1 contains a full 
description of the interventions  
8.3.1 
Questionnaires 
Screening questionnaire 
Questionnaire containing all screening questions to assess whether an individual might be 
eligible for participation, will be distributed prior to the study as part of the screening.  
  
General Questionnaire 
General questionnaire on age, sex, marital status, education, diet, alcohol use, smoking, self-
rated health, current and previous disease, emotional health, and family members will be 
distributed and filled out at baseline. 
 
Daily functioning 
Daily (physical) functioning will be assessed by two questionnaires on performing daily 
activities. Katz Activities of Daily Living (ADL)(36) includes activities such as bathing and 
feeding, while the Lawson Instrumental Activities of Daily Living (IADL)(37) questionnaire 
includes mainly household activities such as cooking and doing laundry. 
 
Quality of life 
The EQ-5D-3L(38), self-reported measure of functional health and well-being will be distributed 
and filled out. It consists of 5 questions on different domains. Additionally, participants will fill 
out the EQ-VAS.(38) 
 
Comorbidities 
From the medical records, we will derive the number of medications used and the co-
morbidities, from which we can constitute the Charlson Comorbidity Index.(39) 
 
Frailty 
Frailty will be measured by the clinical frailty scale.(40) Participants will be categorized on a 
scale from 1 (very fit) to 9 (terminally ill). Additionally, participants will fill in the G8(41), a short 
multidimensional assessment of 8 dimensions. The score ranges from 0-17 at which a score 
of 14 or lower suggests a full geriatric screening is necessary. Filling out the G8 takes 
approximately 3-5 minutes. 
 
Medication use 

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At baseline, we will ask the participants to hand in a list of medications that they are currently 
using retrieved from their pharmacy or GP which will be checked by the research nurse 
together with the participant on the baseline measurement day in the research center. 
 
Medical history 
At baseline, we will ask participants to hand in a list of medical history and current medical 
diagnoses requested and retrieved from their GP which will be checked by the research nurse 
together with the participant on the baseline measurement day in the research center. 
 
Subjective sleep quality 
Sleep quality will be assessed by the Pittsburgh Sleep Quality Index (PSQI) which is a 
questionnaire with different questions on sleep quality in the past month. The questionnaire 
consist of 19 questions on 7 different domains of sleep problems; Subjective sleep quality, 
sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleep 
medication, and daytime dysfunction. Each of the sleep components yields a score ranging 
from 0 tot 3, with 3 indicating the greatest dysfunction. 
 
Sleep chronotype 
Participants will fill out the MCTQ about their sleep behaviour at baseline to assess their 
chronotype.(42) Individuals are also asked to subjectively rate themselves as one of seven 
possible chronotypes ranging from extreme early (preferring to rise much earlier than others) 
to extreme late. This information is combined to determine the time of day at which the 
respondent is likely to feel most alert, placing them objectively in a chronotype category. The 
scale is scored electronically by the Web site at which it is available. Total scores can range 
from 16 to 86, with the lowest values representing extreme-late chronotypes. 
 
Insomnia Severity Index 
Participants will be asked to fill out the ISI questionnaire (Dutch version) a total of 5 times; first 
time before the start of the study to assess if participants are eligible for the study (sleep 
problem yes/no), the second time on the baseline measurement day which we will use as 
baseline, and finally, they will fill out the ISI questionnaire on the last day of each intervention. 
The ISI questionnaire consists of 7 questions and outcomes include: ‘No clinically significant 
insomnia (0-7 points)’, ‘Subthreshold insomnia (8-14 points)’, ‘Moderate severity clinical 
insomnia (15-21 point), and ‘Severe clinical insomnia (22-28 points)’. According to the 
literature, a score of 10 points is and appropriate threshold when detecting insomnia cases in 
a community sample.(35) Therefore, we will include participants with a score of ≥10 in our 
study. 
 
 
8.3.2 
Mental health investigations 
Ecological momentary assessment 

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During the measurement week, participants will be asked to fill out the eEMA questionnaire in 
the Leuven mPath app (or a similar platform meeting European privacy standards) 5 times a 
day on set times. Participants will receive a pop-up on their smartphones and will have a 
window of 1 hour to fill in the questionnaire. During this 1-hour window, participants will get 
multiple reminders to fill in the questionnaire. The questionnaire consists of multiple questions 
that gather information on current mood/feelings divided into multiple dimensions: positive 
affectivity, negative affectivity, energetic arousal and cognition. A 7-point rating scale will be 
used to answer the questions. To minimize the burden of this repeated questionnaire, the time 
needed to fill out the questionnaire is minimised/limited to approximately 4 minutes. 
 
Subjective sleep quality 
As an addition to the eEMA, two questions will be added to the morning questionnaire, one 
about general sleep satisfaction and one about the participants rested feeling.   
 
Emography 
Objective emotional arousal and stress will continuously be measured by the Cardiowatch 287- 
2 (Corsano Health, The Hague, the Netherlands) through electrodermal activity (measured by 
EDA and GSR). 
8.3.3 
Clinical test/procedures 
Anthropometric measurements 
Weight, height, and waist and hip circumference will be measured with a scale and measure 
in the research center which will be the same for all participants. Weight will be measured with 
the person dressed in light clothing and without shoes. Height will be measured with the person 
in standing position and wearing no shoes. Waist circumference will be measured at the 
midpoint between the lowest rib and the top of the iliac crest with a non-elastic tape and in 
standing position. Hip circumference will be measured at the widest part of the hip with a non-
elastic tape and in standing position. 
 
Body composition 
Body composition will be assessed with bioelectrical impedance analysis (BIA, Omron BF508, 
Omron Healthcare Inc., Kyoto, Japan, or a similar device). This device can measure total body 
water, extracellular water, and intracellular water. The subject should be in a supine position 
for four minutes before the start of the measurement. Throughout the measurement the 
participants’ arms and legs should be slightly apart and the subject should remain motionless. 
The measurement will last approximately one minute. 
 
Hand grip strength 
The handgrip strength measurement will be performed three times with the left hand and 
three times with the right hand using a hand dynamometer. This test will be performed with 
the participants sitting in a chair with armrests in an upright position with arms by their sides 
and the elbows at a 90-degree angle. 
 

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4 meter walking test 
This test assesses gait speed. Participants are instructed to walk a distance of four meters at 
their normal pace. The time the individual needs to cover 4 meters is measured. Gait speed of 
longer than 5 seconds to walk 4 meters (0.8 m/s) suggests an increased risk of frailty and the 
need of further clinical review. 
 
Resting blood pressure  
After a 10-minute rest, systolic and diastolic blood pressure will be measured two times with a 
2-minute interval on the dominant arm by trained staff members using a validated blood 
pressure device. 
 
Continuous heart rate monitoring and heart rate variability 
Participants will wear the Corsano Cardiowatch 287-2 (Corsano Health, The Hague, the 
Netherlands) wrist band on their right wrist continuously during the study period. The wristband 
is multifunctional and is waterproof. Participants will wear the wrist band 24 hours a day. The 
HR is measured using a PPG (photoplethysmogram, i.e., optically obtained volumetric 
measurement) and ECG. The manufacturer supplies the algorithm for converting the 
PPG/ECG signals into a set of HR values. All data from the Cardiowatch is available real time 
and is transferred from the watch to the smartphone using a clinical trial app, developed by the 
provider, which allows the researcher to retrieve live vital sign data while conducting a blinded 
study. From the app, it will be uploaded to the output server through a HIPAA/AVG compliant 
cloud service.  
 
Core body temperature 
Core body temperature will be continuously measured by the Cardiowatch 287-2. This 
parameter will be derived through an algorhythm of combined data from Heatflux sensor and 
PPG signal. Diurnal patterns of core body temperature as well as the time of lowest daily 
temperature will be derived from this data. 
 
Breathing rate and oxygen saturation 
Breaths per minute count and oxygen saturation (%SpO2) will also be derived from the 
Cardiowatch 287-2. Data will continuously be measured throughout the study period. 
 
Objective sleep quality 
Objective sleep quality will be monitored with the Withings Sleep Analyzer (Withings, Issy-les-
Moulineaux, France) and an accelerometer (Corsano Cardiowatch 287-2 (Corsano Health, 
The Hague, the Netherlands)., see text below). Prior to the study, the Withings Sleep Analyzer 
will be installed in the participants bed. A smart phone is required to set-up the device and the 
devices must be connected to a Wi-Fi to be able to send data to the cloud. After set-up no link 
to the smartphone is required. The device must be connected to power. 
 
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To monitor objective physical activity, Raw accelerometery will be derived from the Corsano 
Cardiowatch 287-2 (Corsano Health, The Hague, the Netherlands) on their right wrist during 
the entire study period. Raw data will be collected at 32Hz and will be derived from the 
wristband similar to the variable heart rate monitoring and HRV.   
 
Food capturing 
Participants will log their daily food intake during each measurement week by using a food 
diary that will be distributed prior to the start of the study. Frequency and timing of food intake 
will be assessed. 
 
8.3.4 
Invasive procedures 
Melatonin assessment 
On day 13 of all interventions (second-last day of the measurement week), participants will be 
asked to perform/collect 7 buccal swabs in a time range of 5 hours prior to bedtime to 1 hour 
after bedtime to measure the melatonin pattern DLMO. This measurement will be done 
according to the standard protocol from Chron@Work (Groningen, The Netherlands) in dim 
light conditions. (43) Participants will be carefully instructed beforehand on the procedure 
 
Blood samples 
A total of 62 ml blood will be sampled during the total study period (see Table 8.2). For 
screening purpose, we will sample 3.5 ml (nonfasting) blood for direct measurements of thyroid 
function (TSH, fT4), electrolytes (sodium, potassium), kidney function (eGRF/creatinin), liver 
function (AST, ALT, gammaGT by the Central Clinical Haematology Laboratory (CKHL) of the 
Leiden University Medical Center. At screening and baseline (and subsequently also after each 
intervention) will collect one 2 ml sample of venous blood in a vacutainer on EDTA. This sample 
will be used for direct measurement of haemoglobin, hematocrite, erythrocytes, MCV, MCH, 
MCHV,  thrombocytes, leukocytes (neutrofile granulocytes, lymfocytes, eosinofile 
granulocytes, basofile granulocytes, monocytes)  by the Central Clinical Haematology 
Laboratory (CKHL) of the Leiden University Medical Center, as well as for direct measurement 
of HbA1c the Department of Clinical Chemistry and Laboratory Medicine (CKCL) of the Leiden 
University Medical Center. For each participant, at baseline, and after each of the three 
interventions, we sample 3.5 ml (fasted) blood for batch measurements after completion of the 
study of: Insulin, glucose, eGRF/creatinin, Hs-CRP, Gamma GT, ASAT, ALAT, TSH, and ft4. 
In addition, for each participant, we will also collect after each of the three interventions: 1 x 
2.5 ml Paxgen tubes (for isolation of RNA and measurement of clock gene expression)and 1x 
2 ml EDTA (for metabolomics and proteomics). In addition, for each participant, after each of 
the three interventions, we will collect 2x 3.5 ml serum for Biobanking purposes. Moreover, 
residual biomaterial from this study that has not been used in above stated analysis will be 
transferred to the LUMC Biobank if permission is given by the participant. The regulations of 
the LUMC Biobank will be applicable.  
 
 

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8.5 Replacement of individual subjects after withdrawal 
If a subject withdraws from the study, the participant will not be replaced; the logistics of this 
study make it impossible to enter the study once it has started. We have taken this into account 
with the 10% drop-out rate.  
 
8.6 Follow-up of subjects withdrawn from treatment 
Not applicable 
 
8.7 Premature termination of the study 
Due to the COVID-19 pandemic and the consequential measures, this study could be 
postponed or temporally suspended. We aim to continue when possible and finish the study 
when all participants are included. To minimise the chance of premature termination of the 
study, the study duration will be relatively short. 

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9. SAFETY REPORTING 
9.1 Temporary halt for reasons of subject safety 
In accordance to section 10, subsection 4, of the WMO, the sponsor will suspend the study if 
there is sufficient ground that continuation of the study will jeopardise subject health or safety.  
The sponsor will notify the accredited METC without undue delay of a temporary halt including 
the reason for such an action. The study will be suspended pending a further positive decision 
by the accredited METC. The investigator will take care that all subjects are kept informed. 
 
9.2 AEs, SAEs and SUSARs 
9.2.1 Adverse events (AEs) 
Adverse events are defined as any undesirable experience occurring to a subject 
during the study, whether or not considered related to [the investigational product / trial 
procedure/ the experimental intervention]. All adverse events reported spontaneously 
by the subject or observed by the investigator or his staff will be recorded with an 
exception for minor bruising due to the blood draw. 
 
9.2.2 Serious adverse events (SAEs) 
A serious adverse event is any untoward medical occurrence or effect that  
- 
results in death; 
- 
is life threatening (at the time of the event); 
- 
requires hospitalisation or prolongation of existing inpatients’ hospitalisation; 
- 
results in persistent or significant disability or incapacity; 
- 
is a congenital anomaly or birth defect; or 
- 
any other important medical event that did not result in any of the outcomes listed 
above due to medical or surgical intervention but could have been based upon 
appropriate judgement by the investigator. 
An elective hospital admission will not be considered as a serious adverse event. 
 
The investigator will report all SAEs to the sponsor without undue delay after obtaining 
knowledge of the events.   
 
 
The sponsor will report the SAEs through the web portal ToetsingOnline to the 
accredited METC that approved the protocol, within 7 days of first knowledge for SAEs 
that result in death or are life threatening followed by a period of maximum of 8 days to 
complete the initial preliminary report. All other SAEs will be reported within a period of 
maximum 15 days after the sponsor has first knowledge of the serious adverse events. 
 
9.2.3 Suspected unexpected serious adverse reactions (SUSARs) 
Not Applicable 

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9.3 Annual safety report 
 Not applicable 
 
9.4 Follow-up of adverse events 
All AEs will be followed until they have abated, or until a stable situation has been reached. 
Depending on the event, follow up may require additional tests or medical procedures as 
indicated, and/or referral to the general physician or a medical specialist. 
SAEs need to be reported till end of study within the Netherlands, as defined in the protocol. 
 
9.5 Data Safety Monitoring Board (DSMB)  
According the risk classification (K6.), this study has a negligible risk. Therefore we will not be 
appointing a DSMB. 
 

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10. STATISTICAL ANALYSIS 
All data that will be collected in this study will result in (or be transformed into) quantitative data 
and will either be categorical or continuous. Normal distributions will be checked by visual 
inspection of histograms and QQ plots. Normally distributed variables will be described as 
mean with standard deviation (SD) and non-normally distributed variables will be described as 
median with interquartile range (IQR). Categorical variables will be described as numbers (N) 
and percentages. As we collect data on patterns, we will descriptively present all patterns 
derived in line graphs to visually inspect pattern differences between interventions. Missing 
data will be interpolated/imputed with a standard algorithm in SPSS/ R Software. 
 
10.1 Primary study parameter 
The primary study endpoint will be change in insomnia severity measured by the ISI. We 
will perform a paired t-test (assuming normally distributed data) to examine the difference 
between active morning and active evening. Data will be shown as mean difference, SD 
(or 95% confidence interval), and p-value. A p-value lower than 0.05 will be considered as 
statistically significant. 
  
10.2 Secondary study parameter(s)  
Secondary endpoints include changes in: 
Biological clock function  
• 
Clockgene expression 
• 
Core body temperature (°C) 
o Diurnal pattern 
o Time of lowest temperature 
• 
Melatonin 
o 
Dim light melatonin onset (DLMO) 
 
Physiological parameters 
• 
Heart rate 
o Diurnal pattern 
o Average 
o Resting heart rate 
o Minimum/peak heart rate (5 and 95 percentile) 
• 
Heart rate variability (HRV) 
• 
Breathing rate 
• 
Oxygen saturation (SpO2) 
 
Mental health 
• 
Subjective mood 
o Diurnal pattern of: 
▪ 
Positive affectivity 
▪ 
Negative affectivity 
▪ 
Energy 
▪ 
Fatigue  

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▪ 
Cognition  
• 
(objective) Electrodermal activity (emotional arousal and stress) 
 
Behavioural factors 
• 
Food intake 
o Frequency  
o Timing  
• 
Habitual sleep (Table 8.1) 
o Sleep latency (min) 
o Duration (min) 
o Efficiency (%) 
o Sleep phases (%, min) 
o Awakenings at night (x, min) 
o Rested feeling (subjective, 0-7) 
o General satisfaction with sleep (subjective, 0-7)  
 
Biochemistry 
• 
Glucose metabolism 
• 
Inflammatory markers 
• 
Liver function 
• 
Kidney function 
• 
Thyroid function 
• 
Bone metabolism markers 
• 
White blood cell count 
 
Changes between active morning and active evening will be assessed. Diurnal patterns 
will be calculated through the hourly mean level of for example glucose and will be 
displayed for each condition. Additionally, we will perform sensitivity analysis for both the 
primary endpoint as all secondary endpoints by analyse the changes between the 
sedentary period & active morning, and the sedentary period & active evening. Assuming 
the data is normally distributed, a paired t-test will be used for all analyses and data will be 
shown in as mean difference, SD, and p-value.  
 
10.3 Other study parameters 
Not applicable 
 
10.4 Interim analysis  
Not applicable 

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11. ETHICAL CONSIDERATIONS 
11.1 Regulation statement 
This study will be conducted according to the principles of the Declaration of Helsinki 
(version October 2013 as emended by the 64th WMA General Assembly, Fortaleza, Brazil) 
and in accordance with the Medical Research Involving Human Subjects Act (WMO). 
 
11.2 Recruitment and consent 
This protocol will be submitted to the Medical Ethics Committee of Leiden Delft and The 
Hague and will not commence before formal approval has been granted. 
Subjects will be recruited from the general population through advertisement in local media 
(e.g. newspapers and radio) and at community centres and local initiatives for older adults 
in Leiden and surroundings. After a subject has expressed interest and has met all inclusion 
criteria, subjects will be given oral and written explanation about the study after which they 
give written acknowledgement of informed consent to participate (E2.). Only hereafter, the 
study procedures will start. 
 
11.3 Objection by minors or incapacitated subjects (if applicable) 
Not applicable 
 
11.4 Benefits and risks assessment, group relatedness 
All study components are minimally or non-invasive. Appendix B shows the frequency and 
duration of all study procedures. We include (repeated) questionnaires on well-being and 
mood and we ask the participants to repeatedly perform buccal swabs which can might be 
experienced as burdensome for some participants. Additionally, we ask participants to 
adhere to the different aspects regarding sedentary behaviour and exercise timing thus 
controlling and restricting their daily schedule to some extent. Further, blood withdrawal will 
be performed, which is a minimally invasive procedure which may cause a small 
hematoma. 
 
Benefits of participation in the current study include free of costs training sessions guided 
by a professional that may lead to health benefits related to increased physical activity 
level, and in beneficial long-term behavioural changes.  
 
 

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11.5 Compensation for injury 
The sponsor/investigator has a liability insurance which is in accordance with article 7 of 
the WMO. 
  
The sponsor (also) has an insurance which is in accordance with the legal requirements in 
the Netherlands (Article 7 WMO). This insurance provides cover for damage to research 
subjects through injury or death caused by the study. 
The insurance applies to the damage that becomes apparent during the study or within 4 
years after the end of the study. 
 
11.6 Incentives (if applicable) 
Participants will get a financial compensation of €250,- including compensation of possible 
travel costs for completing the total study. During the centre visits participants will be 
provided with some refreshments. 
 
12. ADMINISTRATIVE ASPECTS, MONITORING AND PUBLICATION 
12.1 Handling and storage of data and documents 
Prerequisite is the voluntary approval of the participants by signing the informed consent 
prior to inclusion. For all participating subjects, a Case Record Form (CRF) will be 
completed in CASTOR. All subjects will be identified by a study ID-number, in a coded form 
(OPTID00). We will ensure that the privacy of the participants will be protected. The 
participant personal information (name, address) in CASTOR will be encrypted and only 
the principal investigator, dr. 
, and the main researcher, 
, will 
have access. During the study, the research nurses who are in contact with the participants 
will have access to this personal information in order to make the research schedule. The 
research data will be stored in a digital, protected, CASTOR database that is only 
accessible to the researchers of this study. After exporting the data from CASTOR, the 
databases will be stored on a secured local network drive of the LUMC with access by 
authorized persons. The collected data and biomaterials will be stored for 15 years. 
Residual biomaterial that has not been used for this study and data collected in this study 
will be transferred to the LUMC Biobank if permission is given. The regulations of the LUMC 
Biobank  will be applicable. Data and biomaterials will be stored in the biobank indefinitely. 
Participants can at any moment withdraw from the study. Data that has been collected and 
measurements that has been performed in biomaterials can still be used, but residual 
biomaterials will be destroyed. 
 
Data collected by the Withings Sleep is sent directly to the Withings server. Data will be 
stored on Withings servers and will subsequently be transferred to CHDR servers via 

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application programming interface (API). After data collection, CHDR creates an export of 
the data and shares it with LUMC. All data collected from the Corsano Cardiowatch will be 
exported through encryption (according to AVG regulation). No third party will have access 
to participant data. A data processor agreement (or joint controllership agreement) will be 
signed by all parties handling participant data. All data at the CHDR and Corsano servers 
will be deleted at the end of the study once all data is safely stored at a protected drive in 
the LUMC. 
12.2 Monitoring and Quality Assurance  
Intensity of monitoring depends on the risk classification of this study, which will be 
determined in consultation with the monitoring coordinator of LUMC after approval of this 
research protocol. Monitoring will be executed by (internal) monitors of the LUMC according 
to the monitor plan 
12.3 Amendments  
Amendments are changes made to the research after a favourable opinion by the 
accredited METC has been given. All amendments will be notified to the METC that gave 
a favourable opinion.  
 
12.4 Annual progress report 
The sponsor/investigator will submit a summary of the progress of the trial to the accredited 
METC once a year. Information will be provided on the date of inclusion of the first subject, 
numbers of subjects included and numbers of subjects that have completed the trial, 
serious adverse events/ serious adverse reactions, other problems, and amendments.  
 
12.5 Temporary halt and (prematurely) end of study report 
The investigator/sponsor will notify the accredited METC of the end of the study within a 
period of 8 weeks. The end of the study is defined as the last patient’s last visit.  
 
The sponsor will notify the METC immediately of a temporary halt of the study, including 
the reason of such an action.  
    
In case the study is ended prematurely, the sponsor will notify the accredited METC within 
15 days, including the reasons for the premature termination. 
 
 Within one year after the end of the study, the investigator/sponsor will submit a final study 

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report with the results of the study, including any publications/abstracts of the study, to the 
accredited METC. 
 
12.6 Public disclosure and publication policy 
journals and (inter)national conferences, according to the CCMO statement of publication 
policy. An overview of general results will also be communicated to the participants via 
newsletters. In accordance to the ICMJ guidelines, parties that have contributed 
significantly to the study, will be included as co-authors in publications when applicable. 

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13. STRUCTURED RISK ANALYSIS  
Not applicable 
 
 
 

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14. REFERENCES 
 
1. Liu F, Chang HC. Physiological links of circadian clock and biological clock of aging. 
Protein Cell. 2017;8(7):477-88. 
2. Benjamin EJ, Blaha MJ, Chiuve SE, Cushman M, Das SR, Deo R, et al. Heart Disease 
and Stroke Statistics-2017 Update: A Report From the American Heart Association. 
Circulation. 2017;135(10):e146-e603. 
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15. Appendix 
15.1 Appendix A 
 
 
Example of study schedule during an intervention 

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15.2 Appendix B 
Overview of the frequency and duration of all study procedures  
 
Study procedure 
How many 
times/days 
Duration  
(+/- min, p/x) 
Questionnaires Screening questionnaire (by phone) 
1x 
10 
General questionnaire 
1x 
10 
Katz-ADL 
1x 
10 
Lawton IADL 
1x 
10 
EQ-5D-3L 
1x 
15 
EQ-VAS 
1x 
2 
CCI 
1x 
- 
CFS 
1x 
5 
G8 
1x 
3-5 
Medication use 
1x 
- 
Medical history 
1x 
- 
Pittsburgh Sleep Quality Index 
 
 
Munich Chronotype Questionnaire 
1x 
10 
Insomnia severity index 
5x 
5-10 
Mental health 
Ecological momentary assessment 
5x p/d, 21 days 
3-5 
Emography 
42 days 
- 
Clinical 
procedures 
Anthropometric measurements 
2x 
15 
Body composition 
2x 
15 
Hand grip strength 
1x 
5 
4 meter walking test 
1x 
3 
Resting blood pressure 
1x 
5-10 
Heart rate variability  
42 days 
- 
Continuous heart rate monitoring 
42 days 
- 
Breathing rate 
42 days 
- 
Oxygen saturation 
42 
- 
Objective sleep quality 
42 days 
- 
Objective physical activity 
42 days 
- 
Food capturing 
+/- 5x p/d, 21 
days 
3 
Melatonin assessment 
7x p/d, 3 days 
2 

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Core body temperature 
42 days 
- 
Blood sampling 
4x 
10