The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12617000123347
Ethics application status
Approved
Date submitted
6/12/2016
Date registered
24/01/2017
Date last updated
24/01/2017
Type of registration
Retrospectively registered

Titles & IDs
Public title
Cardiovascular Benefits of Commuter Cycling
Scientific title
Effects of Commuter Cycling on Cardiovascular Fitness in Healthy Adults
Secondary ID [1] 290692 0
nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
cardiovascular disease 301234 0
hypertension 301235 0
adiposity 301236 0
Condition category
Condition code
Cardiovascular 300994 300994 0 0
Hypertension
Public Health 301015 301015 0 0
Health promotion/education

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
A 10-week intervention will be conducted in which participants will be asked to ride 20+ min/day 3-5 days/week at a self-selected intensity. A minimum ride time of 100 min a week, accumulated over at least 3 days will be necessary to remain in the project. Participants will be allowed one week of less than 100 minutes of cycling (e.g. illness, travel) but must be made up by adding an extra week to the intervention. Bikes, riding accessories and guidelines will be provided. Two 1 h “training and support” sessions will be held by the Master's student (who is also a bike mechanic) to familiarise participants with bike handling, basic maintenance, road rules and a discussion of routes in and around Dunedin (where the trial will take place). These will occur at baseline and in week 3 of the intervention.
Attendance at these sessions (and all required measures) will be mandatory to participate/remain in the trial and keep the bikes. Attendance will be registered.
In addition to activity logbooks which will be collected weekly, participants will be given a downloadable HR monitor to be worn during all waking hours for 3 consecutive days at baseline, in week 4 and in week 8. Heart rate data in weeks 4 and 8 will be used to corroborate cycle commute information from activity logs, including intensity of commute. (Accelerometers are notoriously poor for identifying cycling.)
Intervention code [1] 296573 0
Lifestyle
Comparator / control treatment
Control group (CON)
Control subjects will be asked to maintain their present physical activity levels and dietary habits during the same intervention period to provide comparison for any seasonal and individual variation. They will be provided with $150 worth of petrol vouchers or public transport vouchers for completion of all measures.
Control group
Active

Outcomes
Primary outcome [1] 300413 0
Maximal oxygen consumption (VO2max)
This measure is indicative of aerobic fitness and inversely correlated with cardiovascular disease and all cause mortality.
An incremental exercise test to exhaustion will be performed on a Velotron Elite cycle ergometer (RacerMate Inc., Seattle, Washington, USA) to determine VO2max and maximum power achieved. Respiratory gas exchange will be measured, breath-by-breath, with open circuit spirometry (Cosmed Cardio Pulmonary Exercise Testing, CosmedSrl, Rome, Italy) and averaged into 30 s blocks.
The protocol for the cycle test will start with a five minute warm up at 75 w with a pedalling cadence between 80-95 revolutions·min-1 (rpm). Visual and verbal feedback will be used to assist with maintaining pedalling cadence . The protocol starts at 100 w and increases in 50 w increments every three minutes until a heart rate (HR) of 165 beats·min-1 (bpm) is achieved. Above 165 bpm, stages increases in 25 w increments until exhaustion, defined by plateau in VO2 with increased workload. If no plateau is observed, exhaustion will be defined as inability to pedal greater than 60 rpm in addition to one of the following criteria: RER equal to or greater than 1.1 or maximal age-predicated HR (+/- 10 bpm).
If participants are unable to complete the VO2max protocol, a second attempt will be permitted prior to exclusion from the study. In this case, the resistance on the cycle ergometer will be reduced to a 50 w warm up, with the first stage at 75 w and 25 w increase every three minutes until exhaustion, as defined above.
Timepoint [1] 300413 0
Prior to (baseline) and upon completion of intervention
Testing sessions performed by participants prior to the intervention will be repeated upon completion, with replication of the procedures and in chronological order that that all baseline tests were implemented.
Primary outcome [2] 300414 0
HDL cholesterol
Plasma samples analysed with a COBAS Mira Plus analyser (Roche Diagnostic, Basel, Switzerland).
Timepoint [2] 300414 0
Prior to (baseline) and upon completion of intervention
In the morning, at least 48 hours after their last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages.
Primary outcome [3] 300415 0
Resting blood pressure- by manual sphygmomanometry
Timepoint [3] 300415 0
Prior to (baseline) and upon completion of intervention
In the morning, after resting supine for 15 min, at least 48 hours after the last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages, and before blood sampling.
Secondary outcome [1] 329916 0
Heart rate sampling (continuous except showering and sleeping).
Portable heart rate monitors (wrist "watch" with chest strap). to measure the impact of cycle commuting on physical activity levels and to validate and quantify diary data.
Timepoint [1] 329916 0
Over 3 day periods, Prior to intervention (baseline), and during weeks 4 and 8 of the intervention,
Secondary outcome [2] 329917 0
HOMA-IR
Fasting plasma insulin and glucose concentrations will be used to predict insulin sensitivity (HOMA-IR).
Glucose will be analysed in duplicate with a Cobas c 111 (Roche Instrument Centre, Rotkreuz, Switzerland) and insulin with the electrochemiluminescence method using an Elecsys2010 (Roche/Hitachi, Tokyo, Japan). The homeostatic model assessment for insulin resistance (HOMA-IR) will be calculated using Matthews et al. (1985):
HOMA(IR) =(Insulin (uU/ml) ×Glucose(mmol/L))/22.5


Timepoint [2] 329917 0
Prior to (baseline) and upon completion of intervention
In the morning, at least 48 hours after their last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages.
Secondary outcome [3] 329919 0
Body composition (DXA scan (in CYC only), sum of skinfolds, body mass, BMI, waist:hip ratio).
[DXA will only be performed in intervention group due to financial constraints.]
Timepoint [3] 329919 0
Prior to (baseline) and upon completion of intervention
Secondary outcome [4] 329920 0
Physical activity (logbooks and International physical activity questionnaire -(IPAQ))
Activity logbooks will be provided for daily logs to record all leisure time physical activities and commuting activities > 5 min and will be include Ainsworth’s Compendium of Physical Activities to improve reliability of perceived intensity.


Timepoint [4] 329920 0
The logbooks are to be kept daily from baseline throughout the intervention, with weekly collection.
IPAQ to be administered at baseline (week 0) and on weeks four and eight.
Secondary outcome [5] 329958 0
Resting heart rate- with a recordable Polar RS400 (Polar Electro Inc., Kempele, Finland) heart rate monitor (comprising a wrist band and chest strap)
Timepoint [5] 329958 0
Prior to (baseline) and upon completion of intervention
In the morning, after resting supine for 15 min, at least 48 hours after the last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages, and before blood sampling
Secondary outcome [6] 329960 0
C-reactive protein, to be analysed in plasma with COBAS Mira Plus analyser (Roche Diagnostic, Basel, Switzerland).
Timepoint [6] 329960 0
Prior to (baseline) and upon completion of intervention
In the morning, after resting supine for 15 min, at least 48 hours after the last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages,
Secondary outcome [7] 329973 0
Health related quality of life
Assessed by the Short form 36 questionnaire (SF-36 survey, Ware & Sherbourne, 1992).
Timepoint [7] 329973 0
Prior to (baseline) and upon completion of intervention
Secondary outcome [8] 330322 0
Total cholesterol analysed with COBAS Mira Plus analyser (Roche Diagnostic, Basel, Switzerland)
Timepoint [8] 330322 0
Prior to (baseline) and upon completion of intervention
In the morning, at least 48 hours after their last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages.
Secondary outcome [9] 330323 0
Triglycerides analysed with COBAS Mira Plus analyser (Roche Diagnostic, Basel, Switzerland)
Timepoint [9] 330323 0
Prior to (baseline) and upon completion of intervention
In the morning, at least 48 hours after their last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages.
Secondary outcome [10] 330324 0
LDL cholesterol determined by Friedewald equation, where cholesterol values are expressed as mmol/L (Friedewald et al., 1972):
LDL Chol.=Total Chol. – (Triglycerides/ 2.18) - HDL Chol.
Timepoint [10] 330324 0
Prior to (baseline) and upon completion of intervention
In the morning, at least 48 hours after their last bout of moderate or high intensity exercise, at least 24 hours from any exercise, at least a 24 hour fast from alcohol and 12 hour fast from food and caffeinated beverages.

Eligibility
Key inclusion criteria
Pass Physical Activity Readiness Questionnaire (PARQ)
Not currently actively commuting and have neither contraindications to exercise nor cardiovascular disease or diabetes.
Minimum age
20 Years
Maximum age
55 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Exclusion criteria includes smoking, active commuting, unemployed or working from home, a BMI > 30, or participating in a structured training program or contraindications to exercise as defined in the Physical Activity Readiness Questionnaire.

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)
allocation not concealed
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
From volunteers, 14 males, 14 females will be quasi-randomised into cycling (CYC) or control (CON) groups. To control for varying levels of fitness, each participant will be paired with one other participant with a similar VO2max and randomly split in to CYC and CON. Randomisation process will be performed separately for males and females to ensure equal representation of sex in each group.
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Repeated measures ANOVA will be used to detect any time-by-group interactions with measures collected in both groups at three or more time points (e.g. physical activity). One-way ANOVA will be performed on the percentage change between pre- and post-intervention measures for data collected at two time points (e.g. body composition, cardiovascular and metabolic parameters). Measures only taken in CYC intervention group (pre- post- DXA) will be compared paired, with 2-tailed T-test.

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 outside Australia
Country [1] 8464 0
New Zealand
State/province [1] 8464 0
Otago

Funding & Sponsors
Funding source category [1] 295117 0
Charities/Societies/Foundations
Name [1] 295117 0
National Heart Foundation
Address [1] 295117 0
9 Kalmia Street
Ellerslie
Auckland, 1051
Postal Address
PO Box 17-160
Greenlane
Auckland 1546
Country [1] 295117 0
New Zealand
Primary sponsor type
University
Name
University of Otago; School of Physical Education
Address
46 Union St West,
PO Box 56
Dunedin 9054
Country
New Zealand
Secondary sponsor category [1] 293937 0
None
Name [1] 293937 0
Address [1] 293937 0
Country [1] 293937 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 296469 0
University of Otago Human Health Ethics Committee
Ethics committee address [1] 296469 0
Manager Academic Committees
Registry PO Box 56
Dunedin 9054
Ethics committee country [1] 296469 0
New Zealand
Date submitted for ethics approval [1] 296469 0
12/07/2010
Approval date [1] 296469 0
27/10/2010
Ethics approval number [1] 296469 0
10/153

Summary
Brief summary
Governmental and other health agencies are encouraging active commuting (e.g. walking or bicycling), which may bring environmental and fiscal benefits, yet knowledge of the effects on overall physical activity levels and health are lacking.
Although walking is practical for short distances, its role in improving cardiovascular health may be limited to older and sedentary populations. Bicycling, on the other hand, is generally performed at an intensity that improves cardiovascular fitness among young and healthy populations. However, few studies have examined bicycle commuting from the perspective of health gains, which have yielded limited and mixed findings. Additionally, whether initiation of a bicycle commuting routine will increase energy expenditure is currently unknown; as energy compensation from other physical activities may occur.
The purpose of this study is to provide quantitative evidence of the contribution (or lack thereof) a daily routine of cycle commuting makes to enhancing physical activity, increasing energy expenditure, and altering physical and mental health parameters among New Zealanders. If changes are observed, these data will give an indication of the magnitude of change that may be expected in these criterion measures with a given increase in activity/energy expenditure, i.e. the relationship between load and response.
Trial website
Trial related presentations / publications
Conference presentations ( & abstracts):
Novis, B.J., Rehrer, N.J. and Hargreaves, E. The effects of commuter cycling
for 10 weeks on fitness, health, and body composition. Sports Medicine
New Zealand Annual Conference Abstracts 37(3):101(2011).
2014 Conference “2 Walk and Cycle 2014” Nelson
http://www.2walkandcycle.org.nz/images/2014_Conference/Rehrer_Nancy_-_Cardiovascular_Benfits_of_Commuter_Cycing.pdf
Public notes

Contacts
Principal investigator
Name 70962 0
A/Prof Nancy J Rehrer
Address 70962 0
School of Physical Education, Sport & Exercise Sciences
Otago University
46 Union St West, PO Box 56
Dunedin 9054
Country 70962 0
New Zealand
Phone 70962 0
+6434799128
Fax 70962 0
Email 70962 0
nancy.rehrer@otago.ac.nz
Contact person for public queries
Name 70963 0
A/Prof Nancy J Rehrer
Address 70963 0
School of Physical Education, Sport & Exercise Sciences
Otago University
46 Union St West, PO Box 56
Dunedin 9054
Country 70963 0
New Zealand
Phone 70963 0
+6434799128
Fax 70963 0
Email 70963 0
nancy.rehrer@otago.ac.nz
Contact person for scientific queries
Name 70964 0
A/Prof Nancy J Rehrer
Address 70964 0
School of Physical Education, Sport & Exercise Sciences
Otago University
46 Union St West, PO Box 56
Dunedin 9054
Country 70964 0
New Zealand
Phone 70964 0
+6434799128
Fax 70964 0
Email 70964 0
nancy.rehrer@otago.ac.nz

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