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Trial registered on ANZCTR


Registration number
ACTRN12616000444482
Ethics application status
Approved
Date submitted
4/04/2016
Date registered
6/04/2016
Date last updated
27/04/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Vascular adaptations to 8 weeks of different types of cycling in healthy older adults.
Scientific title
Vascular adaptations to 8 weeks of different types of cycling in healthy older adults.
Secondary ID [1] 288927 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Vascular health 298266 0
Vascular function 298267 0
Condition category
Condition code
Cardiovascular 298409 298409 0 0
Normal development and function of the cardiovascular system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants will be randomly assigned to one of three 8 week training interventions. All training sessions will be completed at the Murdoch University Exercise Physiology laboratories and will last approximately 40-75 minutes per session (depending on group allocation).

Irrespective of the participant’s group allocation, all exercise sessions will be conducted with groups of up to six participants on a cycle ergometer (WattBike Pro or Trainer, Wattbike Australia, AUS). All exercise intensities will be prescribed according to a predetermined level of perceived exertion, using the Borg 6-20 rating of perceived exertion (RPE) scale, which is associated with a desired percent of aerobic capacity (VO2peak). Each session will begin and end with a 5 minute double-leg cycling based warm-up (intensity; RPE 11-13, 40-60% VO2peak) and cool down (intensity; RPE 8-10, 20-40% VO2peak). The moderate intensity double-leg continuous group will cycle continuously for 40 minutes at an RPE 11-13 (40-60% VO2peak) using normal double-leg cycling. The high intensity double-leg interval cycling group will complete twenty 30 second double-leg efforts at an RPE 15-17 (60-85% VO2peak) with each effort separated by 60 seconds of passive rest (RPE 6; <20% VO2peak). The high intensity single-leg interval cycling group will complete twenty 30 second single-leg efforts at an RPE of 15-17 with each effort separated by 60 seconds of passive rest (RPE 6). At the completion of the first twenty efforts, a short break will be provided (~5 minutes) prior to the participants completing another twenty efforts with the opposite leg.

3 sessions per week will be prescribed and monitored by Miss Nicole Gordon, an ESSA Accredited Exercise Physiologist. Program adherence will be monitored through exercise logs.
Intervention code [1] 294392 0
Treatment: Other
Comparator / control treatment
The moderate intensity double-leg continuous group will be used as the control treatment group as the exercise to be undertaken is recommended by leading sport and exercise groups, such as Exercise and Sports Science Australia and the American College of Sports Medicine, for the improvement and/or maintanence of general health and wellbeing.
Control group
Active

Outcomes
Primary outcome [1] 297881 0
Change in brachial artery flow-mediated dilation will be assessed by noninvasive ultrasound analysis of change in blood vessel size prior to and following occlusion of blood flow using a blood pressure cuff for five minutes.
Timepoint [1] 297881 0
Baseline and 4, 9 and 16 weeks after commencement of intervention.
Primary outcome [2] 297886 0
Change in biomarkers of vascular health and function will be assessed by analysis of a single blood sample for endothelial nitric oxide synthase and vascular endothelial growth factor.
Timepoint [2] 297886 0
Baseline and 4, 9 and 16 weeks after commencement of intervention.
Secondary outcome [1] 322519 0
Changes in maximal aerobic capacity will be assessed through analysis of expired air during a graded exercise test to volitional exhaustion on a Velotron cycle ergometer (RacerMate, USA). Expired air will be analysed by a Parvo TrueOne metabolic cart (ParvoMedics, USA) .
Timepoint [1] 322519 0
Baseline, 9 and 16 weeks after commencement of intervention.
Secondary outcome [2] 322520 0
Changes in maximal cardiac output will be assessed by an automated impedance cardiograph system (Q-Link,PhysioFlow, France) during the graded exercise test to volitional exhaustion on a Velotron cycle ergometer (RacerMate, USA).
Timepoint [2] 322520 0
Baseline, 9 and 16 weeks after commencement of intevention.
Secondary outcome [3] 322521 0
Body composition will be assessed by waist and hip circumference as well as a dual energy xray absorptiometry (DEXA) scan (Discovery Series W, Hologic, USA) for determination of body fat, muscle and bone mineral content.
Timepoint [3] 322521 0
Baseline, 9 and 16 weeks after commencement of intevention.
Secondary outcome [4] 322522 0
Changes in heart structure (left ventricular mass and volumes) will be assessed by a magnetic resonance imaging scan of the heart.
Timepoint [4] 322522 0
Baseline and 9 weeks after commencement of intervention.
Secondary outcome [5] 322526 0
Changes in biomarkers of cardiovascular disease risk will be assessed as a composite outcome by a single fasting blood sample analysing total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, triglycerides, insulin and glucose.
Timepoint [5] 322526 0
Baseline and 4, 9 and 16 weeks after commencement of intervention.
Secondary outcome [6] 323849 0
Changes in physical activity levels outside the structured exercise program being delivered will be assessed by the International Physical Activity Questionnaire.
Timepoint [6] 323849 0
Baseline and 4, 9 and 16 weeks after commencement of intervention.

Eligibility
Key inclusion criteria
1. Healthy older adults between 45 and 75 years old
2. Able to attend Murdoch University Exercise Physiology Laboratory or Curtin University Exercise Physiology Laboratory 3 times per week for 8 weeks for approximately 16 to 30 hours in total (depending on group allocation).
3. Able to attend Murdoch University Exercise Physiology Laboratory for testing sessions at baseline, 4 weeks, 9 weeks and 16 weeks after commencement of the intervention (approximately 7 hours in total).
Minimum age
45 Years
Maximum age
75 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
1. Previously diagnosed with a cardiovascular or metabolic disorder
2. Pregnancy
3. Individuals who smoke regularly or have quit in the last 6 months
4. Must answer “no” the first seven questions in the Exercise and Sports Science Australia pre-screening tool or have a medical clearance from their general practitioner
5. Currently participating in a structured exercise training program, defined as >90 minutes per week of planned exercise for the purpose of improving health and fitness and/or performance

Study design
Purpose of the study
Educational / counselling / training
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Randomisation by computer, and then placed into sequentially numbered, opaque, sealed envelopes.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Safety/efficacy
Statistical methods / analysis
Sample size calculation based on changes in flow-mediated dilation prior to and following 12 weeks of either moderate intensity continuous cycling or increased intensity short duration cycling in older individuals with coronary artery disease [Currie KD et al. (2013). Low-volume, high-intensity interval training in patients with CAD. Med Sci Sports Exerc. 45 (8): 1436-1442.]. We used the mean group change for our calculation (effect size = 0.45, a = 0.05 and power = 0.8). Initial results indicate 14 participants per group was necessary; however we will aim to recruit an additional 20% (i.e. 17 per group) to account for possible drop outs.

All analyses will be conducted on an intention-to-treat basis. Linear mixed modelling will be used to assess differences between interventions for vascular function, endothelial nitric oxide synthase, vascular endothelial growth factor, maximal aerobic capacity, heart strucutre and function, cardiovascular disease risk factors and body composition. Significant main effects or interactions will be analysed using Tukey’s post hoc analysis. Statistical analysis will be performed using SPSS v21.0 data analysis software (SPSS, Chicago, IL) with significance set at p < 0.05.

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)
WA

Funding & Sponsors
Funding source category [1] 293277 0
University
Name [1] 293277 0
School of Psychology and Exercise Science, Murdoch University
Address [1] 293277 0
90 South Street
Murdoch WA 6150
Country [1] 293277 0
Australia
Funding source category [2] 293279 0
University
Name [2] 293279 0
Edith Cowan University
Address [2] 293279 0
270 Joondalup Drive
Joondalup WA 6027
Country [2] 293279 0
Australia
Funding source category [3] 293280 0
University
Name [3] 293280 0
School of Physiotherapy and Exercise Science, Curtin University
Address [3] 293280 0
Kent Street
Bentley WA 6102
Country [3] 293280 0
Australia
Primary sponsor type
University
Name
Murdoch University
Address
90 South Street
Murdoch WA 6150
Country
Australia
Secondary sponsor category [1] 292082 0
None
Name [1] 292082 0
Address [1] 292082 0
Country [1] 292082 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 294755 0
Murdoch University Human Research Ethics Committee
Ethics committee address [1] 294755 0
Room 1.006, Chancellery
Murdoch University
90 South Street
Murdoch WA 6150
Ethics committee country [1] 294755 0
Australia
Date submitted for ethics approval [1] 294755 0
29/01/2016
Approval date [1] 294755 0
14/03/2016
Ethics approval number [1] 294755 0
2016/013

Summary
Brief summary
Exercise training is commonly used for the treatment and prevention of many chronic diseases. Of particular interest are the effects of exercise training to prevent many age-related changes, including reduction in blood vessel health and whole body fitness. Healthy older adults will be recruited to participate in an 8 week exercise training program where they will be randomised to one of three different cycle training groups: moderate intensity double-leg continuous cycling, high intensity double-leg interval cycling, or high intensity single-leg interval cycling. Measures of blood vessel function, heart structure and function, fitness and body composition will be obtained at baseline, 4 weeks (blood sample and vessel function only), 9 weeks and 16 weeks.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 64938 0
Miss Nicole Gordon
Address 64938 0
Room 3.006, Refrectory
Murdoch University
90 South Street
Murdoch WA 6150
Country 64938 0
Australia
Phone 64938 0
+61 448 098 227
Fax 64938 0
Email 64938 0
N.Gordon@murdoch.edu.au
Contact person for public queries
Name 64939 0
Miss Nicole Gordon
Address 64939 0
Room 3.006, Refrectory
Murdoch University
90 South Street
Murdoch WA 6150
Country 64939 0
Australia
Phone 64939 0
+61 448 098 227
Fax 64939 0
Email 64939 0
N.Gordon@murdoch.edu.au
Contact person for scientific queries
Name 64940 0
Miss Nicole Gordon
Address 64940 0
Room 3.006, Refrectory
Murdoch University
90 South Street
Murdoch WA 6150
Country 64940 0
Australia
Phone 64940 0
+61 448 098 227
Fax 64940 0
Email 64940 0
N.Gordon@murdoch.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary