The Effects of Repeated Moderate Overnight Normobaric Hypoxia on Glucose Homeostasis, Appetite, Body Weight, Inflammation and Oxidative Stress in Individuals With Type 2 Diabetes Mellitus
Phase: NA
Conditions: Type2 Diabetes
Sponsor: University of Portsmouth

 
 
 
 
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Study Title:  The effects of repeated moderate overnight normobaric hypoxia on glucose 
homeostasis, appetite, body weight, inflammation and oxidative stress in individuals with type 
2 diabetes mellitus. 
 
Internal Reference No: n/a 
Ethics Ref: 21/SC/0351 
Date and Version No: 14-07-2022 Version: 1.7      
              
Chief Investigator: 
Dr Anthony Shepherd 
Investigators:  
See protocol development team below 
Sponsor:  
University of Portsmouth 
Funder (if applicable): 
Leaders Development Institute  
Signatures:  
 
 
 
 
Protocol Development Team:   
 
Chief Investigator              - Dr Anthony Shepherd     (University of Portsmouth) 
Co-investigator 1                - Associate Prof Jo Corbett  (University of Portsmouth) 
Co- investigator 2               - Associate Prof Zoe Saynor (University of Portsmouth) 
Co-investigator 3                - Dr Rebecca Neal                (Bournemouth University) 
Co- investigator 4               - Dr Heather Massey            (University of Portsmouth) 
Co- investigator 5               - Dr Maria Perissiou       
(University of Portsmouth) 
Co- investigator 6               - Prof Michael Cummings    (Queen Alexandra Hospital) 
Co- investigator 7               - Prof Mike Tipton         
(University of Portsmouth) 
Co- investigator 8               - Prof Mike Grocott             (University of Southampton)       

 
 
 
 
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Co-investigator 9                - Prof Hugh Montgomery     (University College London) 
Co-investigator 10                - Associate Prof Andrew Murray (University of Cambridge) 
Co-investigator 11 
 
- Mrs Janet Rennell-Smyth (PPI member ) 
Co-investigator 12                - Mr Thomas James   
(University of Portsmouth) 
Co-investigator 13 
 
- Dr Janine Makaronidis  
 (University College London) 
              
 
TABLE OF CONTENTS 
 
1. 
AMENDMENT HISTORY 
6 
2. 
SYNOPSIS 
7 
3. 
ABBREVIATIONS 
8 
4. 
BACKGROUND AND RATIONALE 
9 
5. 
PRELIMINARY STUDIES AND EXPERIENCE OF INVESTIGATORS 
9 
6. 
AIMS AND OBJECTIVES 
9 
6.1 
Primary Objective 
9 
6.2 
Secondary Objectives 
9 
7. 
STUDY DESIGN 
10 
7.1 
Summary of Study Design 
10 
7.2 
Primary and Secondary Endpoints/Outcome Measures 
10 
8. 
STUDY PARTICIPANTS 
10 
8.1 
Study Setting 
10 
8.2 
Overall Description of Study Participants 
10 
8.3 
Eligibility Criteria 
10 
9. 
SAMPLING 
11 
10. 
STUDY PROCEDURES 
11 

 
 
 
 
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10.1    Recruitment 
11 
10.2   Screening and Enrolment 
11 
10.3 Randomisation 
11 
10.4 Study Assessments 
12 
10.5 
Discontinuation/Withdrawal of Participants from Study Treatment 
12 
10.6 
Definition of End of Study 
12 
11. 
INTERVENTIONS 
13 
11.1 
Description of Study Intervention / Treatment 
13 
11.2     Adherence to Study Treatment 
13 
11.3     Accountability of the Study Treatment 
13 
11.4     Concomitant Medication / Therapies 
13 
12. 
ASSESSMENT OF SAFETY (if applicable) 
13 
12.1 
Definitions 
13 
12.2 
Reporting Procedures for Serious Adverse Events 
13 
12.3 
Recording and Reporting Procedures for All Adverse Events 
14 
13. 
Data Handling and Record Keeping 
14 
13.1 
Data Collection Forms 
14 
13.2     Data Management 
14 
14. 
DATA ANALYSIS 
14 
14.1      Description of Analysis Populations 
14 
14.2      Analysis of Endpoints 
14 
14.3     Procedure for Dealing with Missing, Unused and Spurious Data 
14 
14.4     Procedures for Reporting any Deviation(s) from the Original Statistical Analysis Plan 
14 
14.5      Interim analysis and criteria for early study termination 
15 
15. 
ETHICS 
15 
15.1 
Participant Confidentiality 
15 

 
 
 
 
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15.2     Other Ethical Considerations 
15 
15.3     Declaration of Helsinki 
15 
15.4     ICH Guidelines for Good Clinical Practice 
15 
16. 
PATIENT PUBLIC INVOLVEMENT (PPI) 
15 
16.1    Study design 
16 
16.2    Study implementation 
16 
16.3    Dissemination 
16 
17. 
FINANCING AND INSURANCE 
16 
17.1    Research Costs 
16 
17.2    Service Support Costs 
16 
17.3    Excess Treatment Costs 
16 
17.4    Study Sponsorship 
16 
18. 
TIMETABLE AND ORGANISATIONAL CHART 
16 
19. 
RESOURCES, EQUIPMENT AND PHYSICAL FACILITIES 
17 
20. 
DISSEMINATION AND OUTCOME 
17 
21. 
REFERENCES 
17 
22. 
APPENDIX 1     SCHEDULE OF PROCEDURES 
17 
23. 
APPENDIX 2    STUDY FLOW CHART 
17 
24. 
APPENDIX 3    PARTICIPANT INFORMATION SHEET 
17 
25. 
APPENDIX 4    INFORMED CONSENT FORM 
17 
26. 
APPENDIX 5    SAMPLE QUESTIONNAIRES 
17 
27. 
APPENDIX 6    SAMPLE DATA COLLECTION FORMS 
17 
28. 
APPENDIX 7    DRUG INFORMATION (SUMMARY OF PRODUCT CHARACTERISTICS)
 
17 
29. 
APPENDIX 8 MANUFACTURERS BROCHURE FOR NOVEL EQUIPMENT 
17 

 
 
 
 
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30. 
APPENDIX 9 CONTRACTUAL AGREEMENTS WITH OUTSIDE CONSULTANTS / 
COLLABORATORS 
/ 
INSTITUTIONS 
(E.G. 
INDUSTRY, 
CONTRACT 
RESEARCH 
ORGANISATIONS) 
17 

 
 
 
 
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1. 
AMENDMENT HISTORY 
Amendment 
No. 
Protocol 
Version No. 
Date issued Author(s) of changes 
Details of Changes made 
1 
1.2 
22-12-21 
Dr A Shepherd 
1) 
Added Dr Janine 
Makaronidis to the 
protocol team 
2) 
Added details of 
stabilisers to blood 
collection tubes for specific 
analysis (i.e. incretins, 
ghrelin and leptin).  
2 
1.3 
26-01-22 
Dr A Shepherd 
1) 
Added details on 
additional faecal analysis  
 
3 
1.4 
16-03-22 
Mr T James 
1) 
Changed threshold 
for FEV1:FVC ratio lung 
function test in screening 
visit. 
4 
1.5 
26-04-22 
Mr T James 
1) 
Added GP text 
messages for recruitment. 
5 
1.6 
23-06-22 
Mr T James 
1) 
Increase 
recruitment  capacity from 
15 to 20 individuals. 
6 
1.7 
14-07-22 
Dr A Shepherd 
1) Increase recruitment  
capacity from 20 to 23 
individuals. 

 
 
 
 
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2. 
SYNOPSIS 
Study Title 
The effects of repeated moderate overnight normobaric hypoxia on glucose 
homeostasis, appetite, body weight, inflammation and oxidative stress in 
individuals with type 2 diabetes mellitus. 
Internal ref. no. 
n/a  
Problem statement 
The number of people with type 2 diabetes mellitus (T2DM) continuing to 
rise, this pandemic is expected to reach 700 million people by 2045. T2DM 
is a metabolic condition characterized by progressive insulin resistance and 
chronic 
hyperglycemia 
(high 
blood 
glucose 
concentrations). 
Hyperglycaemia increases the risk of both micro- and macrovascular 
damage, whilst interventions that reduce blood glucose mitigate this risk. 
Weight loss, achieved through exercise and dietary modification, is 
effective at reducing hyperglycaemia. However, despite the clear benefits 
of exercise and weight loss, diverse psychological, sociological and 
logistical factors can make it difficult for some individuals with T2DM to 
initiate, or adhere to, these lifestyle interventions.  Alternative approaches 
to treatment are therefore required.   
The purpose of this research project is to investigate whether 10-days of 
overnight exposure to moderate hypoxia is effective at improving blood 
glucose control in individuals with T2DM and to provide insight into the 
physiological mechanisms responsible for any beneficial effects. 
Research question / 
hypothesis 
Aims: 
The primary aim of this research project is to investigate whether a 10-days 
of overnight moderate hypoxia can improve blood glucose control in 
individuals with T2DM. 
Objectives: 
Specifically, our objective is to assess a novel therapeutic intervention for 
the treatment and management of T2DM which overcomes many of the 
barriers to uptake and adherence that are associated with some lifestyle 
interventions such as exercise and weight loss.  
Hypothesis  
We hypothesise that 10-days of overnight moderate hypoxia will:  
1. 
Improve glucose control   
2. 
Improve insulin sensitivity  
3. 
Reduce appetite / food intake 
4. 
Reduce body mass 
5. 
Improve inflammatory status  
6. 
Improve redox balance 
7. 
Increase gut anaerobe content   
 
8. 
Maintain habitual physical activity  
9. 
Have no effect on sleep quality 

 
 
 
 
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Study Design 
Single blind, randomized, balanced, crossover design study (i.e. participants 
will undergo both the hypoxia and sham conditions and will be blinded to 
the conditions in which they are in).  
Study Participants 
Individuals with type 2 diabetes  
Planned Sample Size 
The study of 23      subjects provides adequate power (including a 15% drop-
out rate typically seen in our clinical trials): 13 subjects are required to 
detect a 1 standard deviation change [30] in venous blood [glucose] during 
a 2 hour oral glucose tolerance test (OGTT (alpha = 0.05; power = 80%)).  
Follow-up duration 
1 months washout – 10 day intervention  
Planned Study Period 
1 year  
Primary Objective 
Post-intervention (sham vs hypoxia) area under curve for venous blood 
[glucose] during a 2 hour OGTT.  
Secondary Objectives 
Fasting venous blood [glucose], peak venous blood [glucose] during OGTT, 
Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), daily 
glucose excursions (continuous glucose monitoring), and untargeted 
metabolomics, body mass / composition change, hormonal markers of 
appetite (e.g. leptin and ghrelin), food intake, gut microbiome, markers of 
inflammatory status (e.g. interleukin-6; nitrite), redox balance (TNFɑ; 
SOD), HIF-1α, extracellular HSP70, physical activity and sleep quality.  
Primary Endpoint 
Post-intervention (sham vs hypoxia) area under curve for venous blood 
[glucose] during a 2 hour OGTT. 
Secondary Endpoints 
See secondary objectives.  
Intervention (s) 
10 days of moderate home-based overnight normobaric hypoxia (FIO2 = 
~0.155, or sham hypoxia intervention (FIO2= 0.2093) using hypoxic 
‘pillow tents’.  

 
 
 
 
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3. 
ABBREVIATIONS 
 
CHaRT 
Clinical, Health and Rehabilitation Team  
CRF 
 
Clinical record folder  
FIO2 
 
Fraction of inspired oxygen  
HOMA-IR 
Homeostatic Model Assessment for Insulin Resistance  
NHS             National Health Service 
T2DM  
Type 2 diabetes mellitus  
 

 
 
 
 
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4. 
BACKGROUND AND RATIONALE 
 
Type 2 diabetes mellitus (T2DM) is a metabolic condition characterized by progressive insulin 
resistance and chronic hyperglycemia (high blood glucose concentrations) (10).  
Hyperglycaemia increases the risk of both micro- and macrovascular damage, whilst 
interventions that reduce blood glucose mitigate this risk (32). Weight loss, achieved through 
exercise and dietary modification, is effective at reducing hyperglycaemia (22). However, 
despite the clear benefits of exercise and weight loss, diverse psychological, sociological and 
logistical factors can make it difficult for some individuals with T2DM to initiate, or adhere to, 
these lifestyle interventions (1, 9). With the number of people with T2DM continuing to rise, 
this  pandemic is expected to reach 700 million people by 2045 (24). Thus, there is a clear need 
for cost-effective interventions that can effectively improve glycaemic control in people with 
T2DM and which people will adhere to. 
 
A simple exposure to a lowered concentration of inspired oxygen (i.e. hypoxia) may represent 
such an intervention. In addition to the beneficial effects on glucose homeostasis that have been 
reported following a single acute hypoxic exposure, repeated intermittent, or continuous, 
hypoxic exposure may also have therapeutic potential in individuals with T2DM. In rodent 
models, daily hypoxic exposures returned fasting blood [glucose] to normal levels and 
increased glucose transporter 4 translocation in mice with T2DM (6, 35). Similar effects on 
glucose homeostasis have been shown in overweight humans (17) and those with insulin 
resistance, (during intermittent hypoxic training) which was explained, at least in part, by 
reduction in body mass (~ 1.2 kg) (27).  
 
Another mechanism for hypoxia induced weight loss could be a shift in the gut microbiome. 
The gut is a hypoxic environment and as the body becomes systemically hypoxic, anaerobes 
are likely to become more dominant (11). Some anaerobes are fermenters which not only 
produce alcohol but also short and medium chain fatty acids which can be metabolised (2, 25). 
Specifically, the hypoxia-inducible factor (HIF) pathway is attenuated with upregulation of the 
pyruvate kinase 1 and subsequent inhibition of pyruvate dehydrogenase (21). Moreover, the 
gene encoding PPAR is selected for during high altitude which leads to a shift in fatty acid 

 
 
 
 
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oxidation to glycolytic pathways (19) which in turn will lead to reduction in oxidative 
phosphorylation and thus oxygen demand, with more efficient oxygen utilisation. 
 
Although hypoxia has received little attention in this kind of clinical context, sleeping in 
hypoxic environments is already common practice in competitive endurance athletes who 
attempt to gain an ergogenic benefit through up-regulating erythropoiesis (23). Our own recent 
work has also demonstrated a significant reduction in body mass in athletes following 10-days 
of overnight sleeping in a moderate normobaric hypoxic environment (FIO2 = 0.156) combined 
with moderate daily exercise in a hot environment (23), an effect which did not appear to be 
due to diuresis. The mechanisms underpinning the improved glycaemic control in response to 
hypoxia are likely multifactorial. Animal data and in vitro human skeletal muscle work (8) 
suggest that hypoxia may function as an exercise mimetic (i.e the physiological response to 
exercise without moving) by acting on the same (insulin independent) signalling pathway as 
that stimulated by muscle contraction, although improved insulin sensitivity in some studies 
(e.g. (18)) implies that insulin-dependent glucose transport may also have been favourably 
influenced. Hypoxic stress also activates the hypoxia inducible factor (HIF) pathway, which 
increases basal metabolic rate, suppresses appetite (20) and promotes a substrate shift towards 
glucose (15) (i.e. larger anaerobic contribution which is less efficient). HIF activation also 
induces the heat shock response and increases heat shock protein (HSP) expression which 
improves insulin resistance and glucose homeostasis in rodents and humans (16). Any 
reduction in appetite and associated body weight-loss is also likely to be important given that 
body mass reduction is linked to improved glycaemic control in individuals with T2DM (36).  
 
In summary, T2DM is a condition that affects a significant proportion of the global population, 
with unsustainable health care implications. This project has the potential to deliver a novel, 
home based, non-invasive therapeutic intervention for individuals with T2DM. However, there 
is a dearth of evidence in people with T2DM to show the mechanisms for any beneficial effects. 
Importantly, the proposed intervention may overcome a number of barriers to uptake and 
adherence that are associated with these lifestyle interventions, which we anticipate will 
facilitate higher levels of uptake and compliance. As a consequence, this intervention has the 
potential to improve outcomes in individuals with T2DM, and to deliver significant financial 

 
 
 
 
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savings in terms of the clinical care costs associated with the treatment of type 2 diabetes 
mellitus.  
 

 
 
 
 
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5. 
PRELIMINARY STUDIES AND EXPERIENCE OF INVESTIGATORS 
Dr Ant Shepherd’s research focuses on using novel interventions (for example; extreme 
environments or nutrition) to improve metabolic and cardiovascular health, quality of life and 
physical function. Ultimately, his research revolves around patient benefit. In the past 3 years 
he has been the principal investigator or co-investigator on over £1,300,000 of funded projects 
related to understanding chronic diseases and/or assessing simple, low cost interventions which 
might improve health. He primarily works with individuals with type 2 diabetes mellitus (and 
different forms of insulin resistance) (3, 13, 26, 29, 31) but has also worked with a number of 
different clinical conditions (including obesity, end stage renal disease, cystic fibrosis, 
Raynaud’s phenomenon, chronic obstructive pulmonary disease and stroke). He recently led a 
randomised  controlled trial  examining the effect of passive heating in individuals with type 2 
diabetes (12). He is currently examining the effect of acute periods of hypoxia on appetite, 
substrate utilisation and glycaemic control in overweight and obese individuals. 
 
Associate Prof Corbett’s research examines the impact of environmental stressors (heat, cold 
and hypoxia) on performance, health and disease. His recent work has included a range of 
clinical groups including individuals with cystic fibrosis, type 2 diabetes, overweight and 
obesity. His recent work has shown the utility of an acute passive heating intervention in 
elevating heat shock protein in individuals with type 2 diabetes (12) important because 
decreased levels of heat shock protein correlate with insulin resistance. His current research 
addresses the role of chronic heat exposure in regulating heat shock protein expression, and 
glucose tolerance, in individuals with type 2 diabetes. Also recently, he has studied the utility 
of using oxygen saturation variability (entropy) (4) and network physiology approaches (14) to 
identify the negative sequelae of hypoxemia, and to develop non-invasive methods by which 
to assess the engagement of the respiratory control system in health and disease. He leads an 
ongoing program of work that builds from previous research demonstrating significant body 
mass reductions in athletes with 10 days of overnight hypoxic exposure (23), and is examining 
the role of hypoxia on appetite, substrate utilisation and glycaemic control in overweight and 
obese individuals. 
 
Professor Cummings is Consultant Physician in Diabetes and Endocrinology at Portsmouth 
National Health Service Trust and Honorary Professor of Diabetes and Endocrinology at 
University of Portsmouth. He is Clinical Lead (Diabetes) for the Comprehensive Local 
Research Network for the National Institute for Health Research), Wessex. He is also Head of 
the DOVE (Dysglycaemia, Oxidative stress and the Vascular Endothelium) research 
programme and associate Editor for the journal Practical Diabetes and Sub-Editor for Diabetes 
Digest. His responsibilities will be to help with participant recruitment, screening of 
electrocardiograms (ECGs) and blood profiles. He will also help monitor the occurrence of 
adverse events.  
 
Professor Tipton is a Professor of Human & Applied Physiology, director of our world leading 
Extreme Environments Laboratory at the University of Portsmouth and Editor in Chief of 
Experimental Physiology (a flagship journal of the physiological society). He is a world leader 
in extreme environmental physiology, and in the effect of hypoxia on human physiology. His 
responsibilities will involve helping with conceptualising the study, data interpretation and 

 
 
 
 
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reviewing of reports and manuscripts. He will act in a senior advisory role, and will mentor 
other members of the team.  
 
Professor Montgomery is a Professor of Intensive Care Medicine at University College London, 
where he directs the Centre for Human Health and Performance. He is also a consultant in 
intensive care at the Whittington Hospital in North London. He has published over 500 papers, 
and has a 25-year history of studying the physiological response to hypoxia in sickness and in 
health. He was research lead for the 2007 Caudwell Xtreme Everest research programme. He 
has also run a large number of clinical investigations, and large scale randomised human trials. 
He has contributed to conceptualising the study and will assist in data monitoring, interpretation 
and analysis, and will review and co-author reports and manuscripts as may be sought. 
 
Professor Grocott is Professor of Anaesthesia and Critical Care at the University of 
Southampton and Consultant in Critical Care Medicine at University Hospital Southampton 
NHS Foundation Trust. He leads the Critical Care Research Area within the Southampton 
NIHR Respiratory Biomedical Research Centre, is Head of the Integrative Physiology and 
Critical Illness Group at the University of Southampton and is Director of the Xtreme Everest 
Hypoxia Research Consortium. His responsibilities involve conceptualising the study, helping 
with data interpretation, reviewing of reports and manuscripts. 
 
Associate Prof Zoe Saynor is a Senior Lecturer in Physical Activity, Exercise and Health at the 
University of Portsmouth and lead for the Physical Activity, Health and Rehabilitation 
Thematic Research Group and the Clinical, Health and Rehabilitation Team (CHaRT). She is 
also an honorary researcher at several NHS Trusts (Portsmouth Hospitals University NHS 
Trust; University Hospitals Southampton NHS Foundation Trust) and has a varied profile of 
national and international clinical research studies. She is experienced in the running of clinical 
trials and is an expert member of several clinical exercise committees, e.g. the European Cystic 
Fibrosis Society Exercise Working Group; UK Exercise and Lifestyle Clinical Studies Group 
as well as being a National Institute for Health Research (NIHR) Applied Research 
Collaboration (ARC) Wessex faculty member. Her responsibilities will involve helping with 
data interpretation, reviewing of reports and manuscripts. 
 
Dr Rebecca Neal (Rendell) is a Senior Lecturer in Exercise Physiology and is an experienced 
environmental physiologist with extensive experience at employing home based hypoxic trials. 
Her responsibilities will involve helping with data interpretation, reviewing of reports and 
manuscripts. She will also help with the logistics of conducting home-based trials having 
published successful at-home hypoxic interventions using the proposed techniques. 
 
Dr Heather Massey is a Senior Lecturer in Sport, Health and Exercise Science. Her main 
research interests are with in Environmental Physiology and has been IRMER trained, with 
recent experience of using the School of Sport, Health and Exercise Sciences DEXA scanning 
equipment. Her responsibilities will involve conducting and interpreting DEXA scans and 
reviewing reports and manuscripts. 
 
Dr Maria Perissiou is a Lecturer in Clinical Exercise Physiology at the University of 
Portsmouth and is an experienced cardiovascular physiologist with experience in running 

 
 
 
 
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research trials in clinical population and people with T2DM. Her responsibilities will involve 
helping with data interpretation, reviewing of reports and manuscripts. 
 

 
 
 
 
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6. 
AIMS AND OBJECTIVES 
Aims: 
The primary aim of this research project is to investigate whether a 10-day overnight moderate 
hypoxia intervention can improve blood glucose control in individuals with T2DM. 
Hypothesis  
We hypothesise that 10-days of overnight moderate hypoxia will:  
1. 
Improve glucose control   
2. 
Improve insulin sensitivity  
3. 
Reduce appetite / food intake 
4. 
Reduce body mass 
5. 
Improve inflammatory status  
6. 
Improve redox balance 
7. 
Increase gut anaerobe content   
 
8. 
Maintain habitual physical activity  
9. 
Have no effect on sleep quality 
 
6.1 
Primary Objective 
Specifically, our objective is to assess a novel therapeutic intervention (hypoxia) on glucose 
AUC during an OGTT.  
6.2 
Secondary Objectives 
Secondary objectives include fasting venous blood [glucose] peak venous blood [glucose] during 
OGTT, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), daily glucose 
excursions (continuous glucose monitoring), body mass / composition change, gut microbiome, 
hormonal markers of appetite (e.g. leptin and ghrelin), food intake, markers of inflammatory 
status (e.g. interleukin-6; nitrite), redox balance (TNFa; SOD), HIF-1α, extracellular HSP70, 
physical activity and sleep quality (accelerometery).  
 

 
 
 
 
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7. 
STUDY DESIGN 
7.1 
Summary of Study Design 
Single blind, randomized, balanced, crossover design study (i.e. participants will undergo 
both the hypoxia and sham conditions and will be blinded to the conditions in which they are 
in). 
7.2 
Primary and Secondary Endpoints/Outcome Measures 
Primary outcome measure 
Post-intervention (sham vs hypoxia) area under curve for venous blood [glucose] during a 2 
hour OGTT. 
 
Secondary outcome measures 
Fasting venous blood [glucose] peak venous blood [glucose] during OGTT, Homeostatic 
Model Assessment for Insulin Resistance (HOMA-IR), daily glucose excursions (continuous 
glucose monitoring), and untargeted metabolomics, body mass / composition change, hormonal 
markers of appetite (e.g. leptin and ghrelin), food intake, gut microbiome, markers of 
inflammatory status (e.g. interleukin-6; nitrite), redox balance (TNFɑ; SOD), HIF-1α, 
extracellular HSP70, physical activity and sleep quality.  
 
 

 
 
 
 
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8. 
STUDY PARTICIPANTS 
8.1 
Study Setting 
The primary and secondary outcomes will be assessed in the Spinnaker building at the 
University of Portsmouth. The Clinical Exercise Physiology Laboratory at the University of 
Portsmouth has a successful history of conducting studies in clinical populations. The 
laboratory contains state of the art equipment that is required for conducting this study and a 
research group involving over 20 academics and researchers. Screening bloods will be assessed 
at Queen Alexandra Hospital, Portsmouth pathology lab or a commercial laboratory. Leptin, 
ghrelin, interleukin-6, TNFa, SOD, HIF-1α and extracellular HSP70 concentrations will be 
quantified using commercially available ELISA assays at UoP (or at UCL with Dr Janine 
Makaronidis). Profiling of the gut microbiome will be analysed between UoP (in Dr Sam 
Robson's Laboratory) and the University of Southampton. Nitrite will be analysed at 
Loughborough University using a Sievers nitric oxide analyser (Sievers NOA 280i, Analytix 
Ltd, Durham, UK) with our established technique (5, 28-31). Metabolomics will be analysed 
at the University of Liverpool (in Professor Warwick Dunn’s laboratory). 
8.2 
Overall Description of Study Participants 
We will recruit 23      participants with T2DM as defined by the World Health Organization to 
take part in our simulated altitude exposure study (i.e. normobaric decreased FiO2).  
8.3 
Eligibility Criteria 
Note: Altitudes < 2,500m (~0.15 FIO2) are similar to those in a commercial aircraft and are 
considered safe for individuals with stable coronary artery disease (Bonadie et al., 2016). 
Inclusion Criteria 
1) 
Males and females with T2DM (as diagnosed with the WHO criteria).  
2) 
Ability to understand the study and provide informed consent.  
 
Exclusion Criteria 
Individuals with contraindications to hypoxic exposure such as; 
1) 
 obstructive sleep apnoea,  
2) 
extant cardiac conditions  
3) 
on medications such as SGLT2 inhibitors or PPAR antagonists  
4) 
glycated haemoglobin < 48  
5) 
sickle anemia,  
6) 
thalassemia,  
7) 
haemoglobinopathy  
8) 
FVC < 80% of predicted FVC 
9) 
FEV1:FVC ratio < 5th percentile for age and sex (as according to the Eurpoean Repiratory 
Society and American Thoracic Society guidelines) (37) .  
 
,  

 
 
 
 
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9. 
SAMPLING 
The study of 20      subjects provides adequate power (including a 15% drop-out rate typically 
seen in our clinical trials): 13 subjects are required to detect a 1 standard deviation change [30] 
in venous blood [glucose] during a 3 hour oral glucose tolerance test (OGTT (alpha = 0.05; 
power = 80%)). Seasonal changes will be recorded and corrected for as a covariate.   
 

 
 
 
 
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10. 
STUDY PROCEDURES 
Consent, screening and familiarisation (visit 1): fam and hypoxic screen 
Once participants have provided fully informed written consent, they will complete a health 
history questionnaire including additional questions specific to exercise in a hypoxic 
environment. This form will be signed off by the Principal Investigator following each 
participants’ responses to the questionnaires to assess eligibility. If there are ANY questionable 
responses, these will be check by our independent medical officers (medcis whose expertise 
are in extreme environments) or our diabetes consultant (depending on the nature of the 
response). Further to this, all participants are required to undertake a spirometry tests and blood 
pressure assessment, provide a venous blood sample and have a 12 lead ECG carried out. Blood 
will be sent for analysis and screened for any health complications that may affect their 
participation in this study including, glycated hemoglobin, sickle anemia, thalassemia, and 
haemoglobinopathy. Results from the 12 lead ECG will be examined by a clinician as will any 
health history questionnaires that demonstrate questionable responses.  
Hypoxic screening and familiarisation  
Participants will be assessed for lung function (FVC and FEV1/FVC ratio, PEF). Participants 
will undergo a one hour, supine exposure to hypoxia (FIO2 = ~0.155, adjusted based upon 
oxyhaemoglobin saturation during pilot hypoxic exposure to ensure target SpO2 of ~88-92 %). 
Participants’ desaturation will be recorded. Anyone who desaturates to below 65 % SpO2 or in 
whom end tidal CO2 or O2 of less than 25 mmHg or 45 mmHg respectfully is recorded. Eligible 
participants will then be randomly allocated (using randomizer.org) to start in either the 
hypoxia or sham condition (see details below). Participants will be sent home with a SpO2 
(Equivital EQ02, Hidalgo, UK) monitor that will record oxygen saturation for 2 nights so that 
we can screen for undiagnosed sleep apnoea. Finally, a time will be scheduled within the next 
two days to set up the hypoxic generator, and the hood at the participant’s home.  
 
Intervention  
Participants will undertake 10 days of moderate home-based overnight normobaric hypoxia 
(FIO2 = ~0.155), and a sham hypoxia intervention (FIO2= 0.2093) using hypoxic ‘pillow tents’ 
in a random order. The use of pillow tents rather than whole body tents was based on patient 
and public involvement (PPI) consultations. Participants will wear an SpO2 monitor at all times 
within the tent that will sound an alarm if SpO2 falls too low. If it sounds, participants will 
remove the hood (so that they breathe ambient air) and leave it off for the remainder of the 
night. An independent medical officer will decide if the participants can remain in the trial. The 
O2 fraction will be set by the researcher and participants instructed not to change the settings. 
Finally participants will be asked to maintain a diary of the time spent in the tent. Finally, 
participants will be asked to record a dietary diary and photograph meals in order to try and 
replicate it in both conditions. Participants will then undertake the alternative condition. The 
cross-over conditions will be separated by a minimum 4 week wash out period. During the 
intervention, as well as recording safety information (ie. SpO2) we will ask participants to wear 
a continuous glucose monitor (CGM) sensor (Abbott Diabetes Care Inc., Alameda, CA, USA) 
on the anterior portion of the upper arm with a small adhesive patch. These sensors will be 
worn for 14 days to determine free-living glycaemic control, in addition to a wrist-worn 
accelerometer (GENEActiv, Activinsights, Kimbolton, Cambridge, UK) to assess baseline 
habitual physical activity (PA) and sleep [32] (see details below in section 10.4).  

 
 
 
 
Page 21 of 44 
 
 
 
 
 
Visit 2, 3, 4 and 5 (approx 2.5 per visit) 
Visits 2-5 are identical in nature. Visits 2 and 4 are baseline visits before each arm of the 
crossover (i.e. the intervention). Visits 3 and 5 are following the 10 day hypoxic or sham 
exposures to assess the outcomes. An OGTT, body composition and venous blood samples and 
a stool collection will occur on each visit. After visit 3 there will be a 4 week washout out 
period. Visit 4 is necessary to ensure participants are back to baseline. During this visit, if 
anyone has had a respiratory tract infection or infectious disease in between visits, the hypoxic 
screening and lung function tests will be repeated. During visit 3, a new CGM sensor will be 
secured and accelerometer worn and a home visit for set-up will be re-booked. At the end of 
visit 5, another CGM and accelerometer will be affixed to the participants to check how long 
the effects of the intervention take to decay.  
Urine collection is critical for our metabolomics analysis.  In order to look for trends across time 
and between conditions we will need to collect urine before, during and after the intervention.  
Participants will be asked to collect a small urine sample for 2 days before the intervention starts, 
for each day of the intervention and for 2 days following the intervention. Participants will be 
provided with instructions on how to collect a mid-flow urine sample and how to safely store 
the samples until they are collected. 

 
 
 
 
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Page 23 of 44 
 
 
 
10.1    Recruitment 
Our typical recruitment rates via GP practices is approximately one in ten people with T2DM. 
GP recruitment will be executed via mail outs and text messages (e.g. We are looking for people 
with type 2 diabetes to sleep at home in slightly reduced oxygen for 10 nights which may help 
manage their diabetes and help them lose weight - click the link to find out more). Recruitment 
via the local DESMOND course (T2DM education clinic) is approximately one in five people 
with T2DM. We will need to approach between 90 and 113 people with T2DM to ensure we 
recruit enough (n = 23) people to account for drop outs.  
10.2   Screening and Enrolment 
For word of mouth recruits, the research team will provide interested parties with an invitation 
letter and the PIS. Our local GP collaborators will send our PIS and a letter which will include 
a free post return slip for potential participants who are interested. A member of the UoP 
research team will attend the DESMOND meeting 3 times a month to advertise, discuss and 
disperse information about the study. 
For actual participant screening following consent, please see part 10 (one page above).  
10.3 Randomisation 
Eligible participants will be randomly allocated (using randomizer.org) to start in either the 
hypoxia or sham condition (see details below). 
10.4 Study Assessments 
 
OGTT 
Fasted blood samples will then be taken for the measurement of plasma glucose and insulin 
concentrations ([glucose] and [insulin], respectively), and these data will be used to calculate 
β-cell function via the HOMA-%B model. Following this, participants will consume 75 g of 
glucose, and blood samples will be taken at 0 and 120 minutes post-glucose ingestion for the 
assessment of plasma [glucose] and [insulin]. Utilising the data from the OGTT protocol, 
insulin sensitivity of those not on insulin will be estimated using Stumvoll’s insulin sensitivity 
index [31].  
 
Dual-energy X-ray absorptiometry (DEXA) scanner 
The scan will be carried out using a DEXA scanner (Holologic, Vertec, UK) operated by a 
trained and qualified researcher (Dr Heather Massey). A whole body scan will be conducted 
on each participant and a post-collection segmental analysis will be conducted afterwards. 
Variables that will be calculated from the scan data are fat density, muscle density and bone 
density; the scan will produce a density value measured in g.cm-3. This will give us a baseline 
analysis of body composition and will allow us to identify if the expected weight loss of the 
intervention is fat or fat free mass.  
 
Continuous glucose monitoring (CGM)  

 
 
 
 
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The sensors (Abbott Diabetes Care Inc., Alameda, CA, USA) will be fixed to the anterior 
portion of the upper arm with a small adhesive patch. These sensors will be worn for 14 days 
to determine free-living glycaemic control.  
Habitual Physical Activity and Sleep (accelerometry) 
Physical activity (PA) and sleep will be assessed using wrist-worn accelerometers 
(GENEActiv, Activinsights, Kimbolton, Cambridge, UK). These devices have previously been 
validated for use in healthy adult populations (7) and are extensively used in clinical studies. 
The GENEActiv accelerometers will measure triaxial movement acceleration in gravity (g) 
units (1 g = 9.81 m/s2) at a frequency of 100Hz continuously over a period of 7 days. The 
Euclidean norm (magnitude) of signals from the three axes minus 1 g (with negative numbers 
rounded zero) will be used to quantify acceleration due to movement in mg (1 mg = 0.00981 
m/s2) (33). Following the measurement periods, data will be downloaded using manufacturers 
software and processed in R (R Core Team, Vienna, Austria) using the open source GGIR 
software package (http://cran.r-project.org) following completion of the study. Previously 
validated acceleration threshold values (in healthy adults) will be used to quantify the time 
(minutes/day) spent on average in each intensity category: total PA, and separately for light, 
moderate, vigorous intensities and the composite category moderate-vigorous PA (MVPA). To 
facilitate comparison with current national PA guidelines PA, average MVPA accumulated in 
bouts of at least 10 minutes will also be calculated.    
 
Sleep variables will be determined from accelerometer data using an open source sleep 
detection algorithm in GGIR software. Sleep metrics derived using this method have 
demonstrated good levels of agreement with both self-report measures of sleep and 
polysomnography (the gold standard). The method of accelerometer based sleep quantification 
used in this study is described in detail elsewhere (34). Briefly, wrist-worn triaxial 
accelerometers allow approximation of the angle of orientation of the arm relative to the 
horizontal plane. Periods of sleep are defined as nocturnal periods characterised by minimal 
movement frequency and magnitude of changes to the angle of the arm which does not include 
day time sleep. Time in bed will be defined as the onset of the first period of sustained inactivity 
(as measured by changes of less than 5 degrees in a rolling 5 minute window) to the end of the 
last period of inactivity. Sleep duration is the sum of all recorded periods of sleep. Sleep 
efficiency can then be calculated as the sleep duration as a proportion of time in bed.  
 
Periods of accelerometer non-wearing will be identified using the range and standard deviation 
(SD) of acceleration values at each axis, calculated for rolling 60 minute windows. Non-
wearing will be indicated if the SD is <13.0 mg or if the range of values is <50 mg for two of 
the three axes. A full explanation of this method can be found elsewhere (33). To allow effective 
assessment of habitual PA and sleep, measurement days when the accelerometer is worn for 
less than 16 hours will be excluded from the final analyses (33). Participants who recorded less 
than 4 days of 16 hours will also be excluded. 
 
Oxygen saturation  

 
 
 
 
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An SpO2 monitor (Equivital EQ02, Hidalgo, UK) will be set up at the participant’s home. 
Participants will wear the monitor at all times during exposure to hypoxia. If saturation falls 
below (65%) an alarm will be sounded. This system also records beat to beat heart rate and will 
store the data on the device until it is collected. Participants will also be asked to maintain a 
diary of the time spent in the tent.  
 
Diet diary  
Participants will be asked to record a dietary diary and photograph meals for all 10 days of the 
intervention in order to try and replicate it in both conditions. This is an important step to enable 
us to assess any changes in the gut microbiome. We appreciate that this is a significant 
participant burden and it will be discussed in the section below.  
 
Biochemistry 
Fasting venous blood [glucose] peak venous blood [glucose] during OGTT, Homeostatic 
Model Assessment for Insulin Resistance (HOMA-IR), hormonal markers of appetite (e.g. 
incretins, leptin and ghrelin*), food intake, markers of inflammatory status (e.g. interleukin-6; 
nitrite), redox balance (TNFa; SOD), HIF-1α and extracellular HSP70. We will also include an 
untargeted metabolomics strategy using two ultra performance liquid chromatography-mass 
spectrometry assays to measure the relative concentration of up to 2000 metabolites (plasma 
and urine). * For analysis of gut hormones, sample collection tubes need to be treated in specific 
ways. For incretin analysis (i.e. GLP-1 and PYY) we will prime the EDTA tubes with a 10 µl 
of DDP-IV inhibitor per mL of whole blood and 100 µl of aprotinin. The tubes are chilled on 
ice, and remain on ice until centrifuged. For analysis of leptin and Desacyl-Ghrelin 100 µl of 
aprotinin is added to an EDTA tube and for Acyl-Ghrelin and additional 20 µl of Pefabloc is 
added. Following centrifugation, both Ghrelin samples will be treated again (475µl of plasma 
to 25µl of Pefabloc). 
 
Gut microbiota 
Stool samples will be frozen at -80°C within 12 hours of collection. Bacterial DNA will be 
extracted using the QIAamp PowerFecal Pro DNA kit according to the manufacturer’s 
instructions (51804, Qiagen, USA) at the end of data collection. The purified extracted DNA 
will be frozen at -80°C. The extracted DNA will be delivered to the University of Southampton, 
National Oceanography Centre, for PCR amplification of the 300 bp reads, V3-4 region of the 
16S rRNA gene. DNA samples will be depleted for host DNA and enriched for bacterial DNA 
using primers spanning the full-length prokaryote-specific 16S rRNA amplicon. In this way, 
host DNA from the individuals will not be analysed, preventing any issues with personal 
identification. 16S rRNA sequencing libraries will be generated for the Illumina MiSeq 
sequencer. Sequenced 16S rDNA sequences will be compared against the SILVA database of 
known 16S rDNA sequences for taxonomic classification. 
 
Comparisons of the gut microbiome will be made using the Alpha (α) diversity levels on basis 
of the observed diversity, Chao1 diversity and Shannon diversity metrics. Variability between 
the cohorts will be identified based on principal coordinates analysis. Significantly 
differentially abundant taxa will be identified between each cohorts’ sample based on the use 
of generalised linear models using the DESeq2 package in R, using a fold change threshold of 

 
 
 
 
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2-fold difference between the cohorts with a p value (adjusted for multiple testing using 
Benjamini and Hochberg correction) <0.05. 
 
Faecal samples will also be analysed (in collaboration with UCL) for short-chain fatty acids 
(acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, hexanoate), alcohols (ethanol, 
1-propanol, 2-propanol, butanol, isobutanol, pentanol)  and indoles (bacterial metabolites of 
tryptophan that have immunomodulatory effects). 
 
10.5 
Discontinuation/Withdrawal of Participants from Study Treatment 
Participants may be withdrawn from treatment, or from the study as a whole; if they ask to 
withdraw, if participant safety is in question or if the study is stopped early.   
10.6 
Definition of End of Study  
The end of study will be the date of the last visit of the last participant.  
 

 
 
 
 
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11. 
INTERVENTIONS 
11.1 
Description of Study Intervention / Treatment 
10 days of moderate home-based overnight normobaric hypoxia (FIO2 = ~0.155, or sham 
hypoxia intervention (FIO2= 0.2093) using hypoxic ‘pillow tents’.  
11.2     Adherence to Study Treatment 
Participants will be asked to confirm compliance and complete a diary confirming the exposure. SpO2 
will be recorded and used as confirmation.  
11.3     Accountability of the Study Treatment 
Ultimately, the chief investigator (Dr Ant Shepherd) is responsible for all aspects of the study. However, 
the appointed post-doctoral researcher will be responsible for installing the hypoxic generators and 
monitoring adherence.   
11.4     Concomitant Medication / Therapies 
Participant involvement is anticipated to be ~2 months. Medication will be recorded on enrolment and 
updated throughout their time in the study. 

 
 
 
 
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12. 
ASSESSMENT OF SAFETY (IF APPLICABLE) 
A serious adverse event is any untoward medical occurrence that: 
·         Results in death, 
·         Is life-threatening, 
NOTE: The term "life-threatening" in the definition of "serious" refers to an event in which 
the participant was at risk of death at the time of the event; it does not refer to an event which 
hypothetically might have caused death if it were more severe. 
·         Requires inpatient hospitalisation or prolongation of existing hospitalisation, 
·         Results in persistent or significant disability/incapacity, or 
·         Is a congenital anomaly/birth defect. 
·         Other important medical events* 
  *Other events that may not result in death, are not life threatening, or do not require 
hospitalisation, may be considered a serious adverse event when, based upon appropriate 
medical judgement, the event may jeopardise the participant and may require medical or 
surgical intervention to prevent one of the outcomes listed above. 
12.2  Reporting Procedures for Serious Adverse Events 
A serious adverse event (SAE) occurring to participant should be reported to the REC that gave 
a favourable opinion of the study where in the opinion of the Chief Investigator the event was: 
‘related’ – that is, it resulted from administration of any of the research procedures; and 
‘unexpected’ – that is, the type of event is not listed in the protocol as an expected occurrence. 
Reports of related and unexpected SAEs should be submitted within 15 days of the Chief 
Investigator becoming aware of the event, using the NRES report of serious adverse event form 
(see NRES website).  
12.3 
Recording and Reporting Procedures for All Adverse Events 
All adverse events will be recorded in participant file notes. Distinction between SAE and AE will be 
made by an independent medical officer. All SAE will be reported to the sponsor and the REC regardless 
of if it is related or not.  
   

 
 
 
 
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13. 
DATA HANDLING AND RECORD KEEPING 
13.1 
Data Collection Forms 
Visit 1 will act as a consent, screening and hypoxic screening to allow for medical clearance. 
All data for these visits will be stored in the clinical record folder (CRF). Separate forms will 
be prepared for; anthropometrics, medical history, screening (i.e. blood pressures etc) and blood 
markers. All paper copies will be stored in the CRF’s.  
13.2     Data Management 
All study data (excluding electronic files) will be entered on paper copies and stored in participant 
CRF’s. Electronic files will be stored on a shared (with access restricted to only the research team) 
google drive. All data will be double data entered into excel. Macro’s will be used to check for anomalies 
and corrected. The participants will be identified by a study specific participants number and/or code in 
any database.  The name and any other identifying detail will NOT be included in any study data 
electronic file. The chief investigator (Dr Ant Shepherd) is responsible for database maintenance and 
management. 

 
 
 
 
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14. 
DATA ANALYSIS 
14.1      Description of Analysis Populations  
All participants who complete all visits will be entered into the analysis as per protocol.  
14.2      Analysis of Endpoints  
All data will be tested for normality using the Shapiro-Wilk test. For normally distributed data, 
paired samples t-tests will be used to assess differences pre and post hypoxic exposures for; 
blood [glucose] (AUC and peak), insulin sensitivity, eHSP70, IL-6, leptin, ghrelin, TNFa, SOD,  
HIF-1α HR, PA and sleep efficiency. For non-parametric data Wilcoxon-Signed rank test will 
be used for pairwise comparisons. Repeated measures one-way analysis of variance (ANOVA) 
will be used to identify differences between conditions for SpO2 and [glucose] across time from 
the CGMs. Mauchly’s test of sphericity will used to determine if any data violated the 
assumption of spherical data. If violated, sphericity will be accounted for using the Greehouse-
Geisser correction. Where significant differences are observed (P < 0.05), post-hoc tests will 
be performed using LSD pairwise comparisons. Effect sizes will be reported as partial eta 
squared (η2p) (small = 0.01; medium = 0.06; large = 0.14) [33]. 
14.3     Procedure for Dealing with Missing, Unused and Spurious Data  
Outliers will remain within the data. Within the data analysis software missing data will be 
coded 9999 and the data point missed during analysis.   
14.4     Procedures for Reporting any Deviation(s) from the Original Statistical Analysis Plan 
For this pilot a SAP is not required (excluding the above).  
14.5      Interim analysis and criteria for early study termination  
Given the small samples size and time frame, no interim analysis will be performed. Early termination 
will only occur if the safety of participants is in question. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
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15. 
THICS 
NHS Local Research Ethics Committee (REC) approval will be obtained prior to 
commencement of the study. The REC, local NHS, research and development department and 
all site specific forms and patient identification centre forms will be forwarded to the funder 
prior to recruitment of participants. Written informed consent will be obtained from all 
participants. Insurance indemnity will be provided by the Sponsor for this study. 
Every effort has been made to keep the risks and discomforts to a minimum but there are some 
risks associated to taking part. Not all volunteers will experience any or all of the risks stated 
below, but participants will be made aware of them. 
1. 
The main burden to you will be a lifestyle alteration because you will be asked to sleep 
in a tent for 2, 10 day periods whilst wear smart monitors. During these periods you will also 
be collecting urine samples and recording your food consumption in diaries.  
2. 
We will also take small blood samples which can cause pain for a short period. 
Likewise, putting the glucose monitors on can cause mild discomfit.  
3. 
The body composition scan involves a mild dose of radiation. All scans in this study 
(per participant) would be equivalent to 3 day of natural background radiation. It is, however, 
the most accurate and appropriate way of assessing the changes in your body across the 
intervention.  
 
15.1 
Participant Confidentiality 
The study staff will ensure that the participants’ anonymity is maintained.  The participants will be 
identified only by initials and a participants ID number on the CRF and any electronic database.  All 
documents will be stored securely and only accessible by study staff and authorised personnel. The study 
will comply with the Data Protection Act which requires data to be anonymised as soon as it is practical 
to do so. 
15.2     Other Ethical Considerations 
N/A 
15.3     Declaration of Helsinki 
The study protocol will be carried out in accordance with the declaration of Helsinki.  
15.4     ICH Guidelines for Good Clinical Practice 
All staff will be GCP trained and will be monitored by the sponsor to ensure adherence to GCP. 

 
 
 
 
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16. 
PATIENT PUBLIC INVOLVEMENT (PPI) 
 
16.1    Study design 
Evidence of patient, carer and public involvement (PCPI): 
The chief investigator has a strong track record of PCPI work having been involved in PCPI 
award winning projects from the UK Stroke Forum (2016) for an acceptability and feasibility 
trial. We have a PCPI co-applicant (Mrs Janet Rennell-Smyth) who has been instrumental in 
the design and development of this study and will continue to be involved in the reporting, 
dissemination and future NIHR funding bids. Other individuals with T2DM have been 
consulted and have stated that they would prefer hoods rather than full tent coverings. Questions 
surrounding the smart technology were made following reviewing the PIS and pictures of the 
technology have been added. The lay summary and patient facing documentation has been 
reviewed by our PCPI co-applicant.   
16.2    Study implementation 
This is a pilot study and as such we do not have a TSC or DMC. Issues will be managed by the senior 
members of the research team. We will endeavor to involve the PCPI member where possible on 
decisions regarding the study and data. 
16.3    Dissemination 
Our PCPI member will help disseminate findings through local groups, local/national media, and co-
authoring the paper. Our PCPI involvement has developed the protocol to this stage and will continue 
to play a large role in this project and the larger definitive trial to come. 

 
 
 
 
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17. 
FINANCING AND INSURANCE 
Total funds are $120,000. The full economic cost for this study is $170,166. Public liability 
and indemnity insurance is covered by the University of Portsmouth.  
17.1    Research Costs  
Total cost ($120,000) 
Total funds funded are $120,000. In order to keep the cost within the maximum budget the 
University of Portsmouth have only requested 11% ($13,013) of the available 15% overhead 
costs. The full economic cost for this study is $170166. Please see table 1 for the overview and 
text below for the detailed justification.  
Table 1. Shows the breakdown of the study costs.  
Breakdown of costs  
Full economic costing 
($) 
Funded ($) 
Research Associate 0.7fte 
41402 
41402 
Recruitment 
725 
725 
Consumables and Analysis 
40933 
40933 
Small equipment 
12843 
12843 
Participant travel 
653 
653 
Publication Costs 
2175 
2175 
PI A Shepherd 2 hrs p/w (88 hrs) 
5406 
5388 
CoI Z Saynor 0.34 hrs p/w (2 days) 922 
919 
CoI J Corbett 0.34 hrs p/w (2 days) 1103 
1099 
CoI M Tipton 0.17 hrs p/w (1 day) 853 
850 
Infrastructure technician 
2024 
0 
Estates Costs 
15408 
0 
Indirect Costs 
45719 
13013 

 
 
 
 
Page 34 of 44 
 
 
 
Total ($) 
170166 
120000 
$ displayed are USD.  
Value added to the project  
The Extreme Environments Laboratory at the University of Portsmouth has a 30 year history 
of conducting innovative human research trials. The laboratory contains some of the world’s 
leading facilities for conducting environmental research including three bespoke environmental 
chambers, with temperature, humidity, solar, wind and hypoxia control, and a research group 
involving over 20 academics and researchers. The Institute of Biological and Biomedical 
Sciences at the University of Portsmouth has state of the art laboratories to enable us to analyse 
our biological samples. As well as the bespoke chambers, it hosts portable kit essential for this 
study such as two hypoxic generators (cloud 9), SpO2 monitors (Equivital EQ02, Hidalgo, UK) 
and accelerometers.  
Researcher time (total = $80,536)  
We request funds for an experienced researcher (senior research associate) in order to achieve 
the timeline goals (12 months, full-time = $71,555). They will assist with the day to day running 
of the project, including participant recruitment, study logistics, data collection, inputting and 
analysis (including biochemistry). We will need $725 for recruitment purposes (to ensure we 
get the correct candidate and advertise to the largest audience). Academic staff time for this 
grant totals $8,256. 
Equipment (total = $12,843) 
We will buy two hypoxic systems (cloud 9), and individual pillow tents (tents are not 
transferable between individuals for hygiene reasons and are considered a consumable) from 
Sporting Edge UK Ltd. These units will ensure we can complete this project in the time scale 
of the grant. Total = $12,843 
Consumables (total = $12,956)  
We require $12,956 for consumables so that we can take perform the experiment. Oral glucose 
tolerance tests, blood sampling kits and ELISA kits to analyse the hormones and proteins within 
the blood (including: insulin, HIF, HSP70, nitrate, nitrite, ghrelin, leptin, IL6, IL10, SOD and 
TNFa). Continuous glucose monitors will also be utilised to assess glucose concentrations. We 
have access to GENEActiv accelerometers, as such we are not asking for funds.  
Participant travel (total = $652)  
Our patient and public involvement group (PPI) were clear that funds for travel needed to be 
supported. In line with our other trials we will provide £10 per visit to cover the costs of 
transport (£10 x 3 visits x 15 people = £450 or $652).  
 
 

 
 
 
 
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17.2    Service Support Costs 
17.3    Excess Treatment Costs 
17.4    Study Sponsorship 
 This study is being sponsored by the UoP.

 
 
 
 
Page 1 of 44 
 
 
 
18. 
 
TIMETABLE AND ORGANISATIONAL CHART 
 
 
Figure 1 shows the suggested timeline for the project.

 
 
 
 
Page 1 of 44 
 
 
 
19. 
RESOURCES, EQUIPMENT AND PHYSICAL FACILITIES 
The Extreme Environments Laboratory at the University of Portsmouth has a 30 year history 
of conducting innovative human research trials. The laboratory contains some of the world’s 
leading facilities for conducting environmental research including three bespoke environmental 
chambers, with temperature, humidity, solar, wind and hypoxia control, and a research group 
involving over 20 academics and researchers. The Institute of Biological and Biomedical 
Sciences at the University of Portsmouth has state of the art laboratories to enable us to analyse 
our biological samples. As well as the bespoke chambers, it hosts portable kit essential for this 
study such as two hypoxic generators (cloud 9), SpO2 monitors (Equivital EQ02, Hidalgo, UK) 
and accelerometers. 

 
 
 
 
Page 2 of 44 
 
 
 

 
 
 
 
Page 3 of 44 
 
 
 
20. 
DISSEMINATION AND OUTCOME 
Results (estimates of effect sizes and confidence intervals) from this pilot study will be utilised to define 
our primary outcome and to power a larger, definitive multi-centre randomised control trial with our co-
applicants and collaborators around Europe. Once our final report has been submitted to the funder, we 
will apply for NIHR funding via a researcher-led Research for Patient Benefit (RfPB) or an Efficacy 
and Mechanism Evaluation (EME) bid (depending on the effect size and sample size). The results will 
be disseminated through publication in peer-reviewed scientific and clinical journals and via 
presentations, local, national and international meetings. A summary of the results will be sent to all the 
participants. Finally, an open day and presentation will be carried out where the participants will be 
informed of the study findings and have the opportunity to ask any pertinent questions and/or provide 
feedback. 
 

 
 
 
 
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Page 5 of 44 
 
 
 
21. 
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Eglin CM, Costello JT, Bailey SJ, Gilchrist M, Massey H, and Shepherd AI. 
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Eslinger D, Rowlands AV, Hurst TL, Catt M, Murray P, and Eston RG. Validation 
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Glasgow RE, Hampson SE, Strycker LA, and Ruggiero L. Personal-model beliefs 
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James TJ, Corbett J, Cummings M, Allard S, Young JS, Towse J, Carey-Jones 
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K, Eglin CM, Hopkins B, and Morgan C. TIMING OF ACUTE PASSIVE HEATING ON 
GLUCOSE TOLERANCE AND BLOOD PRESSURE IN PEOPLE WITH TYPE 2 DIABETES: 
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14. 
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shock response regulates insulin sensitivity and glucose homeostasis: pathophysiological 
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