Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12617000582358
Ethics application status
Approved
Date submitted
21/04/2017
Date registered
26/04/2017
Date last updated
26/04/2017
Type of registration
Retrospectively registered

Titles & IDs
Public title
The short- and medium-term effects of moderate-intensity continuous and high-intensity interval training on glucose control and diabetic complications in men with type 2 diabetes following 12 weeks of supervised exercise training
Scientific title
The short- and medium-term effects of moderate-intensity continuous (MICT) and high-intensity interval training (HIIT) on glucose control, macrovascular and microvascular complication markers in men with type 2 diabetes: A randomised controlled trial.
Secondary ID [1] 291749 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Diabetes 302969 0
Condition category
Condition code
Metabolic and Endocrine 302437 302437 0 0
Diabetes
Physical Medicine / Rehabilitation 302452 302452 0 0
Other physical medicine / rehabilitation

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
12 week intervention phase (Fully supervised by a clinical exercise physiologist with 15 years experience):
During a 3-week introductory stage for both groups the cardiovascular component will have moderate intensity (50% eWLmax [estimated maximal workload - personalized from a graded exercise test]) cycling of 10 min (flanked by a 2 min warm-up and 3 min cool-down of 40% eWLmax). The 4-week intermediate stage the MICT group will progress by increasing the training duration to 17:30 min (flanked by a 3 min warm-up and cool-down of 40% eWLmax) and increasing the training intensity to 55% eWLmax. During the same intermediate stage the HIIT group will progress by including 3 bouts of 3:30 min duration at 75% eWLmax, interspersed with similar duration recovery bouts at 45% eWLmax (flanked by a 1:30 min warm-up and 2 min cool-down of 30% and 45% eWLmax, respectively). For the final 5-week advanced stage, the 32 min MICT sessions will include a training duration of 26 min at 55% eWLmax (flanked by a 3 min warm-up and cool-down of 40% eWLmax). The advanced HIIT stage will apply one of two 28-min sprint interval training (SIT) variations every alternate session. The first includes twelve 1-min bouts at 95% eWLmax interspersed with 1 min recovery bouts at 40% eWLmax, (flanked by a 2:30 min warm-up and cool-down of 60% and 40% eWLmax, respectively). The second SIT variation included eight 30-sec bouts at 120% eWLmax interspersed with 2:15 min recovery bouts at 30% eWLmax, (flanked by a 2:30 min warm-up and cool-down of 40% and 25% eWLmax, respectively).
Immediately after the cardiovascular component a water break and three static stretches (triceps, hamstring and chest) will be performed, totaling 5 min, The resistance training component will contain equal exercises and training variables for both groups and maintained a general strength focus with minimal progression or variation during the study intervention. Four compound exercise (seated low row, horizontal leg press, seated chest press and seated hamstring curls) and abdominal crunches are to be completed by the participants using 2 sets of 15 repetitions at 66% of 1-repetition maximum (1RM) during the introductory stage, 3 sets of 10 repetitions at 75% of 1RM during the intermediate stage and 2 sets of 12 repetitions at 75% of 1RM during the advanced stage. All programmes are therefore personalized/progressed and all the one-hour sessions will be conducted individually, during office hours, within a tertiary institution's exercise clinic three times a week for a total of 12 weeks. Adherence to the sessions will be monitored by the lead researcher via a daily attendance and physiological monitoring sheet for all supervised sessions..

6 month independent training phase
On completion of the 12-week exercise intervention phase all participants will be encouraged to maintain their mode of training, independently at an external facility/environment of their choice, for a period of six months.
Intervention code [1] 297861 0
Treatment: Other
Intervention code [2] 297862 0
Rehabilitation
Intervention code [3] 297863 0
Lifestyle
Comparator / control treatment
During the monitoring-only 12-week phase each SP reports to the clinic once a week during which resting parameters of heart rate, blood pressure and blood glucose will be recorded and verbal feedback provided. Additionally, foot inspections will be conducted and body mass measurements graphically recorded on a weight-loss chart. Of note, during the monitoring-only phase participants will not receive any exercise interventions, but will subsequently be randomized to one of the two exercise groups on completion of the phase.
Control group
Active

Outcomes
Primary outcome [1] 301844 0
Glucose control as measured by absolute changes of glycated Haemoglobin (HbA1c) and macro- and micro-vascular complication markers (as described in the secondary outcome fields 2-7).
Timepoint [1] 301844 0
At randomisation, on completion of 12 week intervention phase and on completion of 6 month independent training phase.
Secondary outcome [1] 334016 0
The number of times precautionary respite (by reducing training duration and/or intensity) is provided during the 36 intervention sessions. Monitoring of exaggerated responses of blood pressure, heart rate, perceived extertion, chest pain, muscle/joint discomfort and blood glucose responses will be used to initiate respite.
Timepoint [1] 334016 0
Each of the 36 sessions during the intervention phase will be supervised
Secondary outcome [2] 334145 0
Resting Blood Pressure (a macro-vascular complication primary outcome)
Participants will lie supine on a plinth for 10 min after which BP will be measured at the brachial artery, using the auscultatory sphygmomanometer method, at vertical height of the heart. Bicep circumference will allow for correct selection of cuff size. The first Korotkoff sound registering the systolic BP (SBP) and the fifth Korotkoff sound will register the resting diastolic BP (DBP). The mean of 2 BP measurements obtained 2 min apart will be recorded. To enhance the reliability of this measurement, participants' BP will be measured again 48 h later using the same procedure, with the mean of the 4 recordings being reported. Additionally a standing BP will be taken immediately upon rising from the supine position to evaluate postural hypotension..
Timepoint [2] 334145 0
At randomisation, on completion of 12 week intervention phase and on completion of 6 month independent training phase.
Secondary outcome [3] 334146 0
Body Composition (a macro-vascular complication primary outcome)
Body mass index (BMI). Body mass will be measured using the pre-calibrated HUR-force platform (ALU4, HUR Labs Oy, Tampere, Finland) with participants standing, in short pants, motionless on the platform. Body mass will be recorded to the nearest 10 g. Height will be measured using a wall-mounted stadiometer and recorded to the nearest 1.0 mm. BMI will be calculated and reported as kg/m2.
Waist circumference will be measured according to the International Society for the Advancement of Kinanthropometry (ISAK) guidelines using a non-elastic measuring tape. With the participant standing in the anatomical zero position the waist circumference will be measured in a horizontal plane midway between the last rib and the iliac crest.
Body fat will be measured indirectly using skinfold thickness, according to ISAK at 7 marked skinfold sites (triceps, subscapula, biceps, supraspinale, abdominal, front thigh and medial calf) using a Harpenden skinfold calliper (Baty International, West Sussex, England) and recorded to the nearest 0.1 mm. Body fat will bereported as the sum of the 7 measurements.
Timepoint [3] 334146 0
At randomisation, on completion of 12 week intervention phase and on completion of 6 month independent training phase.
Secondary outcome [4] 334147 0
Lipid Profile (a macro-vascular complication primary outcome)
After the consultation and 48 hours before the initial physiological assessments, overnight fasted blood samples will be collected and analysed at the local hospital’s laboratory. Participants will need to report to the laboratory at 0800 h and a blood sample will be collected from each participant's antecubital vein. Triglycerides, high density lipoprotein cholesterol (HDL), low density lipoprotein cholesterol (LDL), and total cholesterol (TC) will be determined using the enzymatic colorimetric method measured on a cobas® 8000 (cobas c702 [AU1], Roche Diagnostics International Ltd, Rotkreuz, Switzerland) chemistry module.
Timepoint [4] 334147 0
At randomisation, on completion of 12 week intervention phase and on completion of 6 month independent training phase.
Secondary outcome [5] 334148 0
Static Balance (a micro-vascular primary outcome)
The balance assessment will be performed while the participant maintains a quiet barefoot stance on the HUR Labs iBalance+ platform (ALU4, HUR Labs Oy, Tampere, Finland). The software received information (sample rate: 100 Hz) about centre of pressure motion in the anterior-posterior and medio-lateral directions and the resultant Posturogram provided data on trace length (mm), C90 (90% confidence ellipse) area (mm2) and the standard deviation of the velocity (mm/s). Postural stability will be conducted, after calibration checks according to manufacturer’s guidelines, for an eyes open (familiarisation) and eyes closed (analysis) condition. For each condition participants will stand as stable as possible on the rigid platform , for 35-sec, with only the last 30-sec being recorded, with their feet in a joined parallel position and arms relaxed at their sides.
Timepoint [5] 334148 0
At randomisation, on completion of 12 week intervention phase and on completion of 6 month independent training phase.
Secondary outcome [6] 334149 0
Ankle Strength (a micro-vascular primary outcome)
Before the isokinetic assessment, participants will be instructed to warm-up with a 5-min cycle on an ergometer maintaining 60 rpm at a comfortable resistance. To conclude the warm-up 30-sec ankle plantar and dorsiflexion stretches will be performed. Strength assessments will be conducted on a Humac NORM (Computer Sports Medicine Inc., Stoughton, MA) isokinetic dynanometer. The dynanometer ill be pre-calibrated for speed, weight and position following the instructions of the manufacturer. Peak torque values, assessing the ankle joint (of the dominant leg) through full plantar-dorsiflexion range, for the concentric action will be obtained. Absolute isokinetic torque values (gravity-corrected) will be recorded as Newton-meters (Nm). The assessment protocol will be standardised with respect to patient set-up, familiarisation (two sets of three progressive repetitions for the 60°/s trials and rest intervals (30-sec after the familiarisation trial repetitions and 60-sec between the test repetitions) and test repetitions (two sets of three repetitions at 60°/s). The maximum values obtained during the two sets (reciprocal-contractions) will be recorded for analysis. Participants will be assessed in the supine position with a chair back angle of 20° and the knee joint fully extended. Thigh straps will be used for leg stabilisation and participants will be instructed to hold the handles while being verbally encouraged to exert maximal effort during the test.
Timepoint [6] 334149 0
At randomisation, on completion of 12 week intervention phase and on completion of 6 month independent training phase.
Secondary outcome [7] 334150 0
Heart Rate Variability -HRV (a micro-vascular primary outcome)

HRV using the inspiration-to-expiration ratio of the cardiac rhythm’s R-R interval will be used as a marker of autonomic function. To complete the testing procedure, participants (resting in the supine position) will be connected to the ECG and coached to perform deep breathing (six breaths per minute) for a full minute. HRV will be recorded using the longest R-R interval (in milliseconds) during expiration divided by the shortest R-R interval during inspiration. The mean of six of these individual ratios were recorded as the final ratio.
Timepoint [7] 334150 0
At randomisation, on completion of 12 week intervention phase and on completion of 6 month independent training phase.b

Eligibility
Key inclusion criteria
Male participants having type 2 diabetes with written clearance by their General practitioner for participation in supervised physical activity.
Minimum age
35 Years
Maximum age
59 Years
Sex
Males
Can healthy volunteers participate?
No
Key exclusion criteria
Serious recent cardiac, respiratory or musculoskeletal pathologies, neurological disorders, unstable proliferative retinopathy and/or end-stage renal disease. Due to a weight limitation of the cycle ergometer to be used in training, participants exceeding 170 kg are also excluded.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Initial random allocation of 5 paired participants (based on age, glucose control, insulin use, fitness, body mass index and ethnicity) will be administered by a clinician external to the study. Thereafter allocation will be done by using the method of minimization.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomization
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Sample size calculations were based on a predicted difference in HbA1c of 3.0 mmol/mol with a standard deviation of effect of 2.5 mmol/mol, alpha = 0.05, 1- beta = 0.80 with the calculation yielding 11.5 participants per group

Baseline characteristics of the groups will be compared using a one-way ANOVA or the Kruskal-Wallis test when data were not normally distributed with significance of P = 0.05 and post-hoc testing (Tukey) being used to determine significance of difference.
Training variables will be compared using unpaired, two-tailed student t test. A two-way between-groups ANOVA will be used to measure the impact of exercise training (time-effect), and whether the change differs between HIIT and MICT (time*group-effect). One-way ANOVA of change values (or the Kruskal-Wallis) was used to compare intervention-induced differences between groups. Changes in the follow-up groups will be tested with a paired two-tailed Student’s t-test (or the Wilcoxon test when data is not normally distributed).

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
12/01/2015
Date of last participant enrolment
Anticipated
Actual
21/03/2016
Date of last data collection
Anticipated
Actual
17/12/2016
Sample size
Target
24
Accrual to date
Final
23
Recruitment outside Australia
Country [1] 8833 0
New Zealand
State/province [1] 8833 0
Manawatu

Funding & Sponsors
Funding source category [1] 296243 0
University
Name [1] 296243 0
Universal College of Learning
Country [1] 296243 0
New Zealand
Funding source category [2] 296244 0
University
Name [2] 296244 0
Auckland University of Technology
Country [2] 296244 0
New Zealand
Primary sponsor type
Individual
Name
Shohn Wormgoor
Address
U-Kinetics, UCOL, 62 Grey Street, Palmerston North, 4412
Country
New Zealand
Secondary sponsor category [1] 295161 0
Individual
Name [1] 295161 0
Nigel Harris
Address [1] 295161 0
AUT Millennium Campus, 17 Antares Place, Rosedale, Auckland, 0632
Country [1] 295161 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 297483 0
Auckland University of Technology Ethics Committee
Ethics committee address [1] 297483 0
AUTEC, City Campus, AUT, Private Bag 92006, Auckland, 1142
Ethics committee country [1] 297483 0
New Zealand
Date submitted for ethics approval [1] 297483 0
05/11/2014
Approval date [1] 297483 0
08/12/2014
Ethics approval number [1] 297483 0
14/396

Summary
Brief summary
The overall purpose of the research is to assist people with type 2 diabetes mellitus (T2DM) by investigating if there are better ways of exercising so that diabetes and its complications are managed as best possible. One component of the supervised training that will be used is cycling on a stationary bike as this has shown to help people with diabetes (by lowering their blood sugar readings). The difficulty of the cycling is entirely based on the results of each participant's cycling test and is designed to be at a comfortable level of intensity. Another component of the training is resistance training (gym exercises) and this is also used to help people with T2DM. Both these exercise components are done under the safe supervision of Clinical Exercise Physiologists (CEPs) who will monitor you, your blood pressure and other responses to the exercises. Over the weeks as you get fitter and more confident the cycling will be made more challenging so that you continue to receive the benefits that this exercise has to offer. The main purpose of this research project is to determine which method of making it more challenging is better for people with T2DM. One option is to make the cycling last for a longer duration (known as moderate intensity continuous training [MICT]) or, alternatively, by inserting some bursts of high intensity cycling, followed by recovery period (known as high-intensity interval training [HIIT]). It is hypothesised the combined HIIT would be more effective than combined MICT in reducing glycated haemoglobin (HbA1c) and improving diabetic complications during a 12-week supervised intervention in men with T2DM.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 74186 0
Mr Shohn Wormgoor
Address 74186 0
UCOL, U-Kinetics, 62 Grey Street, Palmerston North, 4412
Country 74186 0
New Zealand
Phone 74186 0
+64(0)69527100
Fax 74186 0
Email 74186 0
[email protected]
Contact person for public queries
Name 74187 0
Mr Shohn Wormgoor
Address 74187 0
UCOL, U-Kinetics, 62 Grey Street, Palmerston North, 4412
Country 74187 0
New Zealand
Phone 74187 0
+64(0)69527100
Fax 74187 0
Email 74187 0
[email protected]
Contact person for scientific queries
Name 74188 0
Mr Shohn Wormgoor
Address 74188 0
UCOL, U-Kinetics, 62 Grey Street, Palmerston North, 4412
Country 74188 0
New Zealand
Phone 74188 0
+64(0)69527100
Fax 74188 0
Email 74188 0
[email protected]

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseHigh-intensity interval training is equivalent to moderate-intensity continuous training for short- and medium-term outcomes of glucose control, cardiometabolic risk, and microvascular complication markers in men with type 2 diabetes.2018https://dx.doi.org/10.3389/fendo.2018.00475
N.B. These documents automatically identified may not have been verified by the study sponsor.