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Trial registered on ANZCTR


Registration number
ACTRN12617000894392
Ethics application status
Approved
Date submitted
14/06/2017
Date registered
19/06/2017
Date last updated
19/06/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Effects of resistance, endurance and high intensity interval training in middle-aged overweight and obese men.
Scientific title
Metabolic and anabolic effects of resistance, endurance and high intensity interval training in middle-aged overweight and obese men and the subsequent effects of detraining.
Secondary ID [1] 292198 0
Nil known.
Universal Trial Number (UTN)
U1111-1197-9525
Trial acronym
REHIIT
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Sarcopenia 303678 0
Overweight and Obesity 303679 0
Condition category
Condition code
Diet and Nutrition 303058 303058 0 0
Obesity
Musculoskeletal 303065 303065 0 0
Other muscular and skeletal disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Brief name:
The metabolic and anabolic effects of 6 weeks of resistance (REX), endurance (END) and high intensity interval training (HIIT) with protein supplementation and the subsequent effects of 2.5 weeks of detraining.

Materials:
All people who wish to participate in the study will be provided with a copy of the Letter to Participants and a letter to their GP. Clearance from a GP is necessary as participants will perform maximal exercise testing. All participants will be provided with a copy of the signed study consent form.

Procedures:
Participants will be asked to record their diet using a phone App to meet individual energy and protein (1.3-1.5 g/kg) targets as estimated from the baseline resting metabolic rate test. To assist with diet recording compliance, participants will be provided with a document stating their targets and will receive ongoing feedback in person once every 3 weeks from the study dietitian to ensure they are consuming enough food to assist with expected responses (e.g. increased lean mass) following the exercise interventions. One-on-one diet consults throughout the study will run for 15-20 min each. Participants will also receive high protein supplements (e.g. protein powder, yoghurt, energy bars) to improve adherence to the dietary protocol. On training days, participants will consume a protein shake containing 25-30 g of whey protein following all exercise sessions. On all days of the study, participants will be instructed to spread their protein intake across the day. Further, participants will be instructed not to drink alcohol on training days and restrict alcohol intake to two standard drinks on all days of the study.

All exercise groups described will complete 3 sessions per week for 6 weeks with at least 1 day of recovery separating each session. Exercise sessions will be administered one-on-one or in small groups (2-3 people) depending on the time that each participants chooses to train. To monitor participation adherence, a register of attendance will be completed at every session and participants will be provided with electronic appointments to avoid scheduling conflicts. Participants will be stratified to one of the exercise interventions by lean muscle mass determined from the baseline body composition (DXA) scan. The principal investigator will be responsible for stratification. As the primary outcome of the study is change in muscle cross sectional area, similar baseline muscle masses between each of the groups is essential to avoid biased results post intervention.

HIIT: After warming up at a light intensity for 3 minutes on an exercise bike, participants will perform 10 x 1 min cycling work efforts at 90% of peak power output (PPO) separated by 1 min recovery at 30 W. To finish the session, you will complete a light warm down for 3 min. The efforts will be increased in intensity progressively throughout the program. All exercise sessions will be take place in an exercise physiology laboratory supervised by a qualified exercise scientist.

Detraining: No structured exercise will be allowed for 2.5 weeks following the exercise programs.
Intervention code [1] 298355 0
Prevention
Intervention code [2] 298356 0
Lifestyle
Intervention code [3] 298361 0
Treatment: Other
Comparator / control treatment
REX and END groups will receive identical protein supplementation and dietary support to that of the HIIT group.

REX: The resistance exercise protocol will consist of a whole-body routine using machines and free weights. Exercises will be started at 60-65% of 1 repetition maximum (1RM) at rep ranges of 9-12 to elicit RPE scores of 8-10 (with 10 being maximum effort). Resistance exercise will progressively increase in weight to account for increases in muscle size and strength throughout the program. By week 3 of the program, participants will lift loads at 70-75% of 1RM with rep ranges and predicted RPE scores remaining the same. Mid intervention 1RM testing will take place at the start of week 4 to establish new training loads for the remaining 3 weeks of the intervention. Following week 4 1RM testing, participants will continue to lift loads at 70-77.5% of 1RM with rep ranges and predicted RPE scores remaining the same. All exercise sessions will be take place in a gymnasium supervised by a qualified exercise scientist.

END: Training will vary in intensity and duration however intensities will range between 50-65% of VO2 max and duration between 30-60 min. All exercise will be performed on an exercise bike. All exercise sessions will be take place in an exercise physiology laboratory supervised by a qualified exercise scientist.
Control group
Active

Outcomes
Primary outcome [1] 302437 0
Changes in muscle fibre cross-sectional area (Type I and II) obtained by muscle biopsy and measured by immunohistochemistry following each of the exercise interventions.
Timepoint [1] 302437 0
Baseline, at 7 weeks and 10 weeks after commencement of the intervention.
Primary outcome [2] 302438 0
Changes in whole muscle transcriptome, obtained by muscle biopsy and assessed by microarray analysis.
Timepoint [2] 302438 0
Baseline, at 7 weeks and 10 weeks after commencement of the intervention.
Primary outcome [3] 302447 0
Changes in muscle architecture (muscle thickness, fascicle length, pennantion angle) by 2D ultrasound.
Timepoint [3] 302447 0
Baseline, at 4 weeks, 7 weeks and 10 weeks after commencement of the intervention.
Secondary outcome [1] 336004 0
(PRIMARY OUTCOME)
Changes in blood glucose regulation obtained from venous blood samples by oral glucose tolerance test.
Timepoint [1] 336004 0
Baseline, at 7 weeks and 10 weeks after commencement of the intervention.
Secondary outcome [2] 336031 0
(PRIMARY OUTCOME)
Changes in resting metabolic rate by indirect calorimetry.
Timepoint [2] 336031 0
Baseline, at 7 weeks and 10 weeks after commencement of the intervention.
Secondary outcome [3] 336036 0
(PRIMARY OUTCOME)
Changes in body composition by dual-energy x-ray absorptiometry.
Timepoint [3] 336036 0
Baseline, at 7 weeks and 10 weeks after commencement of the intervention.
Secondary outcome [4] 336039 0
(PRIMARY OUTCOME)
Aerobic capacity by VO2 max testing.
Timepoint [4] 336039 0
Baseline, at 4 weeks, 7 weeks and 10 weeks after commencement of the intervention.
Secondary outcome [5] 336041 0
(PRIMARY OUTCOME)
Maximal strength by 1 repetition maximum testing.
Timepoint [5] 336041 0
Baseline, at 4 weeks, 7 weeks and 10 weeks after commencement of the intervention.
Secondary outcome [6] 336046 0
(PRIMARY OUTCOME)
Physical activity monitoring by accelerometry and inclinometry.
Timepoint [6] 336046 0
Baseline, at weeks 1, 4, and 7-10 after commencement of the intervention.
Secondary outcome [7] 336048 0
(COMPOSITE PRIMARY OUTCOME)
Changes in mood, behaviour and attitude towards physical activity by cognitive testing (i.e. visual analog scale)
Timepoint [7] 336048 0
Baseline, at 7 weeks and 10 weeks after commencement of the intervention.
Secondary outcome [8] 336049 0
Changes in satellite cell activity obtained from muscle biopsy by immunohistochemsitry.
Timepoint [8] 336049 0
Baseline, at 7 weeks and 10 weeks after commencement of the intervention.

Eligibility
Key inclusion criteria
Overweight or obese (BMI 25-35)
Sedentary - less than 150 min of moderate intensity physical activity or 75 min of vigorous intensity physical activity per week.
No type 2 diabetes
Pass the Exercise and Sports Science Australia pre-exercise screening tool and obtain GP clearance to exercise
No injuries preventing exercise


Minimum age
35 Years
Maximum age
45 Years
Gender
Males
Can healthy volunteers participate?
No
Key exclusion criteria
Identified as high risk by GP despite passing all other inclusion criteria
Currently losing weight
Smoker
Participation in structured exercise in the past 6 months
Not willing to use phone App to record diet
Had bariatric surgery in the past
Vegan

Study design
Purpose of the study
Prevention
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
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
Recruitment postcode(s) [1] 16445 0
3065 - Fitzroy

Funding & Sponsors
Funding source category [1] 296734 0
University
Name [1] 296734 0
Australian Catholic University
Address [1] 296734 0
115 Victoria Parade, Fitzroy VIC 3065
Country [1] 296734 0
Australia
Primary sponsor type
Individual
Name
Dr Donny Camera
Address
Level 5
215 Spring St, Melbourne VIC 3000
Mary MacKillop Institute for Health Research
Country
Australia
Secondary sponsor category [1] 295705 0
Individual
Name [1] 295705 0
Professor John Hawley
Address [1] 295705 0
Level 5
215 Spring St, Melbourne VIC 3000
Mary MacKillop Institute for Health Research
Country [1] 295705 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 297963 0
Australian Catholic University Human Resarch Ethics Committee
Ethics committee address [1] 297963 0
Australian Catholic University
North Sydney Campus
NORTH SYDNEY, NSW 2059
Ethics committee country [1] 297963 0
Australia
Date submitted for ethics approval [1] 297963 0
11/05/2017
Approval date [1] 297963 0
15/06/2017
Ethics approval number [1] 297963 0
2017-104H

Summary
Brief summary
High-intensity interval training (HIIT) is becoming more widely recognized as a time-efficient alternative to traditional endurance exercise for improving markers of cardiopulmonary and metabolic health. A major benefit of HIIT is the time-efficiency of a single exercise session which can be completed in under 30 minutes. HIIT involves short, repeated periods of work at or above maximal aerobic capacity interspersed with rest intervals (e.g. 1 min work, 1 min rest repeated 10 times). Given that HIIT requires rapid contraction of type 2 skeletal muscle fibres, as seen with resistance exercise, it is possible that HIIT may also be able to precipitate muscle mass gains. Whether HIIT with protein supplementation can facilitate similar skeletal muscle adaptations reported following resistance exercise, such as hypertrophy, remains understudied in the literature. When an individual stops training (i.e. detraining), loss of adaptation from exercise can occur. However, no study to date has investigated the effects of a short-term (i.e. 2½ weeks) detraining period on measures of strength and aerobic fitness between resistance, endurance and HIIT training.

The purpose of this study is to investigate the metabolic and anabolic effects of 6 weeks of HIIT with protein supplementation on measures of muscle cross sectional area, body composition, resting metabolic rate, blood glucose control, muscle architecture, maximal strength and aerobic capacity in overweight and obese adults.

Study aims:
1. Compare the anabolic/muscle growth effects of six weeks of HIIT with protein supplementation vs resistance exercise with protein supplementation
2. Compare the metabolic effects of six weeks of HIIT with protein supplementation vs endurance exercise with protein supplementation
3. Investigate the metabolic and anabolic effects of a 2½-week detraining period following each of the exercise interventions

Study hypotheses:
1. HIIT with protein supplementation will induce comparable increases in muscle fibre cross-sectional area, lean body mass, whole muscle transcriptome responses, muscle architecture, compared to resistance exercise with protein supplementation
2. HIIT with protein supplementation will induce comparable increases in insulin sensitivity, resting metabolic rate and mitochondrial protein content compared to endurance exercise with protein supplementation
3. Following a 2½-week detraining period, HIIT with protein supplementation will result in comparable losses in muscle cross sectional area, lean body mass, muscle thickness and muscle transcriptome responses compared to resistance exercise with protein supplementation
4. Following a 2½-week detraining period, greater losses in muscle cross sectional area, lean body mass, muscle thickness and muscle transcriptome responses will occur with endurance compared to HIIT exercise
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 75594 0
Dr Donny Camera
Address 75594 0
Level 5
215 Spring St, Melbourne VIC 3000
Mary MacKillop Institute for Health Research
Country 75594 0
Australia
Phone 75594 0
+61 3 9953 3527
Fax 75594 0
Email 75594 0
donny.camera@acu.edu.au
Contact person for public queries
Name 75595 0
Dr Donny Camera
Address 75595 0
Level 5
215 Spring St, Melbourne VIC 3000
Mary MacKillop Institute for Health Research
Country 75595 0
Australia
Phone 75595 0
+61 3 9953 3527
Fax 75595 0
Email 75595 0
donny.camera@acu.edu.au
Contact person for scientific queries
Name 75596 0
Dr Donny Camera
Address 75596 0
Level 5
215 Spring St, Melbourne VIC 3000
Mary MacKillop Institute for Health Research
Country 75596 0
Australia
Phone 75596 0
+61 3 9953 3527
Fax 75596 0
Email 75596 0
donny.camera@acu.edu.au

No data has been provided for results reporting
Summary results
Not applicable