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Trial registered on ANZCTR


Registration number
ACTRN12619001418167
Ethics application status
Approved
Date submitted
25/09/2019
Date registered
15/10/2019
Date last updated
3/05/2021
Date data sharing statement initially provided
15/10/2019
Type of registration
Prospectively registered

Titles & IDs
Public title
Endurance training characteristics and Cardiac Arrhythmias in Cycling
Scientific title
The Effect of Different Aerobic Exercise Characteristics on Cardiac Arrhythmia Rates in Recreational and Elite Cyclists.
Secondary ID [1] 299149 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Cardiac arrhythmias 314232 0
Condition category
Condition code
Cardiovascular 312594 312594 0 0
Other cardiovascular diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
All intervention periods in this study will occur over a period of three weeks each. The number of cycling training session that each individual will undertake is dependent on their habitual training levels. These training sessions will be self-administered by the participants, with their progress and adherence being monitored by researchers via an online training tracker. The training sessions for each participant will be prescribed by an Exercise Scientist with 8 years experience at the beginning of each three week intervention period, and individualised based on their existing habitual training.

High Frequency Intervention
In this intervention participants will undertake training at 33% greater frequency (number of sessions per week) than their habitual exercise. In order to maintain the same volume (total energy expenditure) as their habitual training, this increased frequency will be offset by a 13% decrease in both the average intensity and duration of each session.

High intensity Intervention
In this intervention participants will undertake training at 33% greater average intensity than their habitual exercise. In order to maintain the same volume as their habitual training, this increased intensity will be offset by a 13% decrease in both the frequency and duration of training sessions.

High Duration Intervention
In this intervention participants will undertake training with a 33% greater session duration than their habitual exercise. In order to maintain the same volume as their habitual training, this increased duration will be offset by a 13% decrease in both the frequency and average intensity of training sessions.
Intervention code [1] 315442 0
Early detection / Screening
Intervention code [2] 315443 0
Lifestyle
Comparator / control treatment
As this is a crossover design study, each intervention will serve as the control for each of the others.
Control group
Active

Outcomes
Primary outcome [1] 321382 0
Frequency of cardiac arrhythmia events, ascertained by 24 hour ambulatory holter ECG recording.
Timepoint [1] 321382 0
Post-intervention (after 3 weeks of exercise training)
Secondary outcome [1] 374832 0
Aerobic capacity, ass assessed via a cycling-based graded exercise test to exhaustion with expired gas analysis.
Timepoint [1] 374832 0
Pre-intervention (one day prior to the beginning of the intervention period)

Eligibility
Key inclusion criteria
Participants must be regular cyclists (1 or more bouts of cycling of >30 min per week).
-Participants must be 18 years or older
-Understand both spoken and written English
-Participants must be currently cycling at least 1 session of 1 hour of cycling per week
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
-Any existing cardiac abnormalities or conditions.
-Any musculoskeltal conditions that would impact adherence or completion of the training.

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)
Given the nature of the intervention (exercise prescription), concealment of allocation is not feasible.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Participants will be batch randomised to intervention groups to ensure that equal numbers of individuals complete each sequence of interventions.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
Power analysis was conducted to determine the sample size required for the observation phase of the study (as the observational study design has a higher required sample size than the crossover phase), so used Pearson's R as the assumed statistical test, with a large effect size (d=0.8), significance set at 0.05 and statistical power set at 0.8. This returned a required sample size of 56. Assuming ~30% drop-out rate brings the final participant number for recruitment to 75.

Recruitment
Recruitment status
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

Funding & Sponsors
Funding source category [1] 303688 0
University
Name [1] 303688 0
La Trobe University
Country [1] 303688 0
Australia
Primary sponsor type
University
Name
La Trobe University
Address
Edwards Road, Flora Hill, 3552, Victoria.
Country
Australia
Secondary sponsor category [1] 303795 0
None
Name [1] 303795 0
Address [1] 303795 0
Country [1] 303795 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 304213 0
La Trobe University Human Research Ethics Committee
Ethics committee address [1] 304213 0
Edwards Road, Flora Hill, 3552, Victoria
Ethics committee country [1] 304213 0
Australia
Date submitted for ethics approval [1] 304213 0
21/05/2019
Approval date [1] 304213 0
15/07/2019
Ethics approval number [1] 304213 0
HEC19233

Summary
Brief summary
The aim of the proposed research is to identify the influence of endurance exercise training on rates of cardiac arrhythmia, and how the manipulation of training variables can modify this relationship. Competitive and recreational cyclists will undergo monitoring of exercise and periodic screening for cardiac arrhythmia burden. This study will be run as a randomised, counterbalanced crossover trial with four intervention periods, those being: habitual training levels, high intensity, high frequency and high duration of exercise. Participants will attend laboratorial testing sessions at the beginning and end of each intervention period, where they will be tested for cardiac arrhythmia burden, aerobic fitness and for biochemical markers. During each observation/intervention period their daily exercise training and physical activity will be monitored.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 96162 0
A/Prof Michael Kingsley
Address 96162 0
La Trobe Rural Health School, Edwards Road, Flora Hill, 3552, Victoria
Country 96162 0
Australia
Phone 96162 0
+61354447589
Fax 96162 0
Email 96162 0
Contact person for public queries
Name 96163 0
Mr Luke Daly
Address 96163 0
La Trobe Rural Health School, Edwards Road, Flora Hill, 3552, Victoria
Country 96163 0
Australia
Phone 96163 0
+61354447501
Fax 96163 0
Email 96163 0
Contact person for scientific queries
Name 96164 0
Mr Luke Daly
Address 96164 0
La Trobe Rural Health School, Edwards Road, Flora Hill, 3552, Victoria
Country 96164 0
Australia
Phone 96164 0
+61354447501
Fax 96164 0
Email 96164 0

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?

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
No additional documents have been identified.