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Trial registered on ANZCTR


Registration number
ACTRN12619000819123
Ethics application status
Approved
Date submitted
22/05/2019
Date registered
6/06/2019
Date last updated
7/01/2020
Date data sharing statement initially provided
6/06/2019
Date results information initially provided
7/01/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
Effects of exercise mode on human skeletal muscle and circulating biological networks
Scientific title
Effects of high intensity interval training versus endurance exercise on skeletal muscle and circulating biological networks in healthy adults
Secondary ID [1] 297802 0
None
Universal Trial Number (UTN)
Trial acronym
HIITome
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Metabolic disorders 312163 0
Obesity 313010 0
Condition category
Condition code
Metabolic and Endocrine 310712 310712 0 0
Metabolic disorders
Diet and Nutrition 311516 311516 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The effects of a single bout of high intensity interval training (HIIT) versus a single bout of work-matched continuous endurance exercise on skeletal muscle and circulating biological networks will be investigated in healthy young males.
Overview of design:
Ten healthy sedentary males aged between 18 – 30 years old with a body mass index (BMI) of 18.5 – 24.9 kg/m2 will be recruited to participate in a randomised cross-over study. All participants will complete the HIIT (vigorous intensity; Borg RPE scale 15-16; 5 x 1 minute of cycling at 85% of maximal Watts [Wmax] with 1 minute break in between each interval) and endurance exercise (moderate to vigorous intensity; Borg RPE scale 13-14; 10 minutes of continuous cycling at 50-55% Wmax) protocols in random order on two separate occasions with a minimum 10-day washout between trial days. Baseline testing (body composition data, resting metabolic rate and aerobic capacity) and exercise protocol familiarisation will precede the first trial day. Aerobic capacity, familiarisation and exercise testing sessions will all be conducted one-on-one with a trained exercise scientist, who will also monitor session attendance and adherence to exercise protocols. Rating of perceived exhaustion (RPE) and heart rate will be monitored during aerobic capacity, familiarisation and exercise testing sessions.
Trial days will involve skeletal muscle biopsy and blood sampling before, during, immediately following, 1 hour post and 3 hour post exercise.
Procedures:
Baseline testing and trial days will take place at the Exercise Science laboratory within the Daniel Mannix Building at Australian Catholic University, Melbourne. Participants will attend the laboratory for 5 visits outlined below. Visits 1-3 will occur over a total period of 1-2 weeks. Following these visits, a minimum of 10 days will separate the two trial days (Visits 4 and 5).
Visit 1: Participant meets with researchers to have the study procedures explained prior to obtaining written consent. Additional paperwork including exercise and muscle biopsy screening tools are completed.
Visit 2: Baseline measurements visit: Resting metabolic rate (RMR), Dual-Energy X-Ray Absorptiometry (DXA) and maximal effort cycling (VO2peak) test.
Visit 3: Exercise familiarisation and collection of standardised meal to consume prior to each trial day. During this exercise familiarisation visit, the participant will complete both exercise protocols with each exercise protocol lasting a total of 8-12 minutes (approximately 30 minutes total including warm up and warm down). The two exercise protocols will be separated by a rest period of 15-30 minutes.
Visit 4: Trial day 1: Participants will attend the lab in the morning following consumption of a provided standardised meal the night prior to the trial day and following an overnight fast. A cannula will be inserted and the first muscle biopsy will be obtained. Participants will complete the first randomly assigned exercise protocol (8-12 minutes; approximately 30 minutes total including warm up and warm down), including muscle biopsy and blood sampling.
Visit 5: Trial day 2: Participants will attend the lab in the morning following consumption of a provided standardised meal the night prior to the trial day and following an overnight fast. A cannula will be inserted and the first muscle biopsy will be obtained. Participants will complete the second randomly assigned exercise protocol (8-12 minutes; approximately 30 minutes total including warm up and warm down), including muscle biopsy and blood sampling.

Description of study procedures:
Resting Metabolic Rate test: Participants will lie down in a quiet, dim-lit room for 25 minutes where RMR will be measured using an automated gas analyser. A hood (clear) will be placed over the participants head and connected to the gas analyser. The 25 minutes includes a 10 minute rest period, followed by a 15 minute period of data collection. This test requires the participant to be fasted with no food, fluid or exercise/activity prior to the test.
Body composition assessment: Participants will undergo a whole body DXA scan. Participants will lay supine on the scanning bed for the duration of the 7-15 minute scan (depending on scanning mode; thick or standard; according to weight of the participant). The machine uses small doses (< 1% of the yearly radiation dose) of radiation to estimate tissue density. The total effective dose of radiation has been calculated for the machine and scans to be used in this study by a Medical Physicist. This test requires the participant to be fasted with no food, fluid or exercise/ activity prior to the test. Light clothing with no metal items (i.e. zips, domes, clips, underwire etc.) should be worn (gowns are available if needed), and all jewelry must be removed. All measures will be obtained by trained researchers who hold radiation licences with Victorian Government and comply to the Code of Practice set out by the Australian Radiation Protection and Nuclear Safety Agency.

Aerobic capacity [VO2 peak] test: Aerobic capacity will be assessed by measuring the maximum volume of oxygen (VO2) participants can breathe in and transport to the working muscles while exercising at maximal intensity. After a light 10-minute warm-up on a cycling ergometer (exercise bike), participants will pedal at a fixed intensity (watts) that will increase every 1-2.5 minutes until volitional fatigue. During this test participants will wear a mouthpiece and headpiece that is connected to a tube for the collection of expired air. Following the warm-up, the test will last for 10-15 minutes where the last few minutes should be perceived as exhaustive. A warm-down will be completed after the test finishes. The aerobic capacity test is a vigorous intensity exercise protocol with intensity assessed by RPE, heart rate and oxygen uptake. The total duration of the aerobic capacity test including the warm up, testing and warm down will be approximately 30 minutes.

Muscle biopsy sampling: All muscle biopsy sampling is conducted by an experienced sports medicine physician. In preparation for a biopsy, a small amount of local anesthetic is injected under the skin, which may result in a mild burning sensation while the fluid is injected. A small, 4-5 mm incision is then made into the skin to create an opening for the biopsy needle. There is often a small amount of bleeding from the incision; however, this bleeding is generally minimal. The biopsy needle is then inserted through the incision site.
A small amount of muscle (100-200 mg) is collected and frozen immediately in liquid nitrogen. After each biopsy, the incision will be closed with sterile tape and wrapped with a bandage. Across the 2 trials, a total of 10 muscle biopsy samples will be taken (5 per trial day).

Blood sampling: An in-dwelling venous cannula will be inserted by the doctor performing the muscle biopsies to collect a total of 10 blood samples (12 mL each) equating to a total volume of 120 mL across the entire study period.
Intervention code [1] 314043 0
Lifestyle
Comparator / control treatment
The continuous endurance exercise protocol (moderate to vigorous intensity; Borg RPE scale 13-14; 10 minutes of continuous cycling at 50-55% Wmax) will serve as the comparator/control treatment for this study. In this randomised crossover design, each participant will complete both exercise protocols. Aerobic capacity testing, familiarisation and exercise testing sessions will all be conducted one-on-one with a trained exercise scientist, who will also monitor session attendance and adherence to exercise protocols. Rating of perceived exhaustion (RPE) and heart rate will be monitored during aerobic capacity testing (30 minutes total including warm up, test and warm down; vigorous intensity), familiarisation and exercise testing sessions.

Control group
Active

Outcomes
Primary outcome [1] 319560 0
Determine the effects of a single bout of HIIT versus continuous endurance exercise on skeletal muscle protein post-translational modifications (i.e. phosphorylation status).
Timepoint [1] 319560 0
Skeletal muscle biopsy samples will be obtained before, during, immediately following, 1 hour post and 3 hour post HIIT and endurance exercise protocols to measure skeletal muscle protein post-translational modifications (i.e. phosphorylation status). Each participant will complete the two exercise protocols on two trial days separated by a minimum of 10 days.
Primary outcome [2] 320220 0
Determine the effects of a single bout of HIIT versus continuous endurance exercise on skeletal muscle protein content.
Timepoint [2] 320220 0
Skeletal muscle biopsy samples will be obtained before, during, immediately following, 1 hour post and 3 hour post HIIT and endurance exercise protocols to measure skeletal muscle protein content. Each participant will complete the two exercise protocols on two trial days separated by a minimum of 10 days.
Secondary outcome [1] 368674 0
Determine the effects of a single bout of HIIT versus continuous endurance exercise on regulation of skeletal muscle gene expression (i.e. transcription).
Timepoint [1] 368674 0
Skeletal muscle biopsy samples will be obtained before, during, immediately following, 1 hour post and 3 hour post HIIT and endurance exercise protocols to measure skeletal muscle gene expression and regulation of transcription. Each participant will complete the two exercise protocols on two trial days separated by a minimum of 10 days.
Secondary outcome [2] 369660 0
Determine the effects of a single bout of HIIT versus continuous endurance exercise on plasma hormone and metabolite concentrations. This is a composite and exploratory secondary outcome.
Timepoint [2] 369660 0
Blood samples will be obtained before, during, immediately following, 1 hour post and 3 hour post HIIT and endurance exercise protocols to measure plasma hormone and metabolites. Each participant will complete the two exercise protocols on two trial days separated by a minimum of 10 days.

Eligibility
Key inclusion criteria
Males; 18­ - 30 years; BMI 18.5 - ­24.9 kg/m2; sedentary and have not performed structured physical activity for 6 months prior to recruitment; no cardiopulmonary abnormalities; no injuries; apparently healthy; ability to pass the ESSA pre-exercise screening tool and/or obtain general practitioner clearance to exercise; able to ride a stationary cycle ergometer at high intensity
Minimum age
18 Years
Maximum age
30 Years
Gender
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
Known cardiovascular disease or diabetes mellitus; known gastrointestinal disorder; previous bariatric surgery; major or chronic illness that impairs mobility or eating/digestion; known transmissible disease [e.g. hepatitis, HIV]; known bleeding disorder (i.e. hemophilia A [factor VIII deficiency], hemophilia B [factor IX deficiency], von Willebrand disease, or other rare factor deficiencies including I, II, V, VII, X, XI, XII and XIII); taking prescription medications (i.e. beta-blockers, anti-arrhythmic drugs, statins, insulin sensitising drugs, or drugs that increase the risk of bleeding [i.e. anticoagulants, antiplatelets, novel oral anticoagulants [NOAs], nonsteroidal anti-inflammatory drugs [NSAIDs], selective norepinephrine reuptake inhibitors [SNRI], or selective serotonin reuptake inhibitors [SSRIs]]); habitual physical activity of greater than or equal to 150 minutes per week of moderate-intensity exercise; previous bariatric surgery; smokers; current restriction of dietary intake (i.e. actively trying to diet and lose weight); not being weight stable (+/- 5 kg) for the last 3 months.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sealed opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using computer-generated, randomised sequence. An independent third party will prepare the computer-generated randomisation lists and sealed envelopes for randomisation. Once informed consent is obtained, the sealed randomisation envelope will be opened revealing the trial-condition order.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
Statistical analysis:
Data from the two exercise trials will be analysed using Generalised Linear Mixed Models. Statistics will analyse factor (time: pre-exercise, immediately post-exercise, 1 hr post-exercise, and 3 hr post-exercise) and group (exercise mode: HIIT versus continuous endurance exercise). Statistical significance will be set at p<0.05.

Power calculations:
Power calculations based on primary outcome measures of skeletal muscle protein and post-translational modification responses comparing pre- versus post-exercise from previously published work (Hoffman et al. 2015 Cell Metabolism) has estimated that a sample size of 8 participants is needed to detect a protein or post-translational modification difference of 125% between exercise mode (HIIT versus continuous endurance exercise protocol) with a minimum power of 80% and a probability of 0.05 (2 dependent means (matched pairs), 2-tailed test). Using our experience from previous interventions, we will over-recruit to cover an estimated attrition rate of 20%, thus 10 participants in total will be recruited.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 302584 0
University
Name [1] 302584 0
Australian Catholic University
Address [1] 302584 0
Exercise and Nutrition Research Program
Mary MacKillop Institute for Health Research
Level 5, 215 Spring Street
Melbourne, Victoria 3000
Country [1] 302584 0
Australia
Funding source category [2] 302850 0
Charities/Societies/Foundations
Name [2] 302850 0
Novo Nordisk Foundation
Address [2] 302850 0
Tuborg Havnevej 19
2900 Hellerup
Country [2] 302850 0
Denmark
Primary sponsor type
Individual
Name
Professor John Hawley
Address
Exercise and Nutrition Research Program
Mary MacKillop Institute for Health Research
Level 5, 215 Spring Street
Melbourne, Victoria 3000
Country
Australia
Secondary sponsor category [1] 302208 0
Individual
Name [1] 302208 0
Dr Nolan Hoffman
Address [1] 302208 0
Exercise and Nutrition Research Program
Mary MacKillop Institute for Health Research
Level 5, 215 Spring Street
Melbourne, Victoria 3000
Country [1] 302208 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 302999 0
Australian Catholic University Human Research Ethics Committee
Ethics committee address [1] 302999 0
Manager, Ethics
c/o Office of the Deputy Vice Chancellor (Research)
Australian Catholic University
North Sydney Campus
PO Box 968
NORTH SYDNEY, NSW 2059
Ethics committee country [1] 302999 0
Australia
Date submitted for ethics approval [1] 302999 0
15/11/2017
Approval date [1] 302999 0
11/04/2018
Ethics approval number [1] 302999 0
2017-311H

Summary
Brief summary
The health benefits of exercise in preventing, delaying and treating obesity and metabolic disorders is widely appreciated. In response to endurance exercise, a series of biological networks (i.e. protein, protein post-translational modification, metabolite and gene networks) are engaged in skeletal muscle and the bloodstream to manage the metabolic and mechanical demands of exercise. However, the breadth of biological networks engaged by a single bout of exercise and how these networks differ between modes of exercise (e.g. high intensity interval training [HIIT] versus continuous endurance exercise) is not known. In this randomised crossover trial, healthy sedentary males aged 18-30 will complete a single bout of HIIT and continuous endurance exercise, with at least 10 days between the two trials. Muscle biopsy and blood samples will be collected before, during and after exercise.

The primary purpose of this study is to determine the effects of a single bout of HIIT versus continuous endurance exercise on skeletal muscle protein content and protein post-translational modifications. The secondary purposes of this study are to determine the effects of a single bout of HIIT versus continuous endurance exercise on skeletal muscle gene expression, as well as plasma hormone and metabolite responses. We hypothesise that a single bout of HIIT or continuous endurance exercise will result in comparable changes in exercise and post-exercise skeletal muscle protein content. In addition, we hypothesise that HIIT will result in greater increases in exercise and post-exercise whole skeletal muscle protein post-translational modifications (i.e. phosphorylation), gene expression (i.e. transcription), and hormone and metabolite responses compared to continuous endurance exercise.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 92126 0
Dr Nolan Hoffman
Address 92126 0
Exercise and Nutrition Research Program
Mary MacKillop Institute for Health Research
Level 5, 215 Spring Street
Melbourne, Victoria 3000
Country 92126 0
Australia
Phone 92126 0
+61 3 9230 8277
Fax 92126 0
Email 92126 0
nolan.hoffman@acu.edu.au
Contact person for public queries
Name 92127 0
Miss Bridget Radford
Address 92127 0
Exercise and Nutrition Research Program
Mary MacKillop Institute for Health Research
Level 5, 215 Spring Street
Melbourne, Victoria 3000
Country 92127 0
Australia
Phone 92127 0
+61 3 9230 8284
Fax 92127 0
Email 92127 0
bridget.radford@acu.edu.au
Contact person for scientific queries
Name 92128 0
Dr Nolan Hoffman
Address 92128 0
Exercise and Nutrition Research Program
Mary MacKillop Institute for Health Research
Level 5, 215 Spring Street
Melbourne, Victoria 3000
Country 92128 0
Australia
Phone 92128 0
+61 3 9230 8277
Fax 92128 0
Email 92128 0
nolan.hoffman@acu.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
Study protocol
Ethical approval
How or where can supporting documents be obtained?
Type [1] 6311 0
Study protocol
Citation [1] 6311 0
Link [1] 6311 0
Email [1] 6311 0
nolan.hoffman@acu.edu.au
Other [1] 6311 0
Attachment [1] 6311 0
Type [2] 6312 0
Ethical approval
Citation [2] 6312 0
Link [2] 6312 0
Email [2] 6312 0
nolan.hoffman@acu.edu.au
Other [2] 6312 0
Attachment [2] 6312 0
Summary results
Have study results been published in a peer-reviewed journal?
No
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary