Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12619001113145
Ethics application status
Approved
Date submitted
23/07/2019
Date registered
12/08/2019
Date last updated
22/10/2021
Date data sharing statement initially provided
12/08/2019
Date results information initially provided
22/10/2021
Type of registration
Retrospectively registered

Titles & IDs
Public title
How hot do your muscles get during intense exercise?
Scientific title
Human muscle, core and skin temperature responses to high-intensity interval and resistance exercise
Secondary ID [1] 298803 0
None
Universal Trial Number (UTN)
U1111-1237-3618
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Exercise-mediated adaptations 313754 0
Condition category
Condition code
Physical Medicine / Rehabilitation 312159 312159 0 0
Other physical medicine / rehabilitation

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Each participant is to attend 1 familiarisation and 3 sessions consisting of combined resistance exercise (RE) and high-intensity interval exercise (HIIE). Sessions to be 1 to 4 weeks apart per participant, and standardised for time of day within participants, and no strenuous exercise beforehand on each day.

The intervention consists of measuring muscle, core (oesophageal and rectal) and skin temperature responses to 3 different profiles each of unilateral RE and HIIE. RE and HIIE to occur in the same session, with RE first because it has the least thermal effect so baseline oesophageal temperature is reattained more quickly (15-30 min between finishing RE and starting HIIE).

RE:
3 unilateral bicep curl RE sessions each with a different protocol: strength, hypertrophy and endurance. Order of sessions for each participant at investigators' discretion but will attempt to randomise.

Strength (1RM) to be determined in a familiarisation session, and used to allocate the intensity for each RE session as follows:
A. Strength: 6 sets of 6 repetitions @ 85% 1RM
B. Hypertrophy: 3 sets of 10 repetitions @ 70% 1RM
C. Endurance: 3 sets of 30 repetitions @ 35% 1RM
Rest between all sets will be approximately 2 min.

HIIE:
3 HIIE single-leg cycle sessions using electromagnetically-braked cycle ergometry of the ipsilateral lower limb. Order of sessions for each participant at investigators' discretion but will attempt to randomise.

Peak power output (PPO) will be determined in a familiarisation session using incremental exercise to exhaustion. The intensity for each HIIE as follows:
A. 10 x 1 min intervals @ 95% PPO with 1 min recovery between intervals
B. 3 x 4 min intervals @ 80% PPO (or maximum sustainable intensity if unachievable), with 3 min recovery between intervals
C. 15 min continuous exercise at 65% PPO (or maximum sustainable work rate if this becomes too high).

Measurements:
Muscle temperature with needle and in-dwelling thermocouples administered by supervisors (Drs Kate Thomas and Jim Cotter) who are experienced in these measurement procedures.
Core (rectal and oesophageal) and skin temperatures with thermistors administered by two MSc students (Tom de Hamel and Ben Smith).

These trials will be undertaken on each of 4-5 participants (dependent on availability of volunteers, as this is only a pilot study for a training study).
Intervention code [1] 315083 0
Treatment: Other
Comparator / control treatment
For RE, strength and endurance are to be compared against hypertrophy resistance exercise.
For HIIE, the two interval protocols are to be compared against 15 min continuous cycling.
Control group
Active

Outcomes
Primary outcome [1] 320809 0
Muscle temperature response to each session of bicep curls and HIIE; muscles to be measured are biceps brachii and vastus lateralis for RE and HIIE, respectively, measured at 2.5 cm using flexible, indwelling T-type thermocouples continuously, and solid needle probe thermocouples intermittently throughout rest periods. Outcomes to be described, and subjected to modelling (for determining parameters of exponential responses to each form of exercise) if data quality is sufficient.
Timepoint [1] 320809 0
Muscle temperatures (indwelling thermocouples) measured continuously (every second) for duration of exercise protocol and for up to 15 min after completion of both RE and HIIE for respective muscles.

Solid needle probe thermocouples intermittently throughout rest periods (every second for 1-3 min). Specifically, at baseline, then after 1 set (of RE) or bout (of HIIE), and for 15-min continuously following completion of all sets.
Primary outcome [2] 320973 0
Mean skin temperature response to each session of RE and HIIE via skin thermistors.

Timepoint [2] 320973 0
Skin temperature measured continuously (every second) for the duration of each exercise protocol and for up to 15 min after completion of exercise.
Secondary outcome [1] 372921 0
Core temperature (oesophageal and rectal) response to exercise, as assessed by 400-series thermistors.
Timepoint [1] 372921 0
Core temperature measured continuously (every second) for the duration of each exercise protocol and for up to 15 min after completion of exercise.

Eligibility
Key inclusion criteria
Volunteers willing to have muscle temperature measured using flexible thermocouples during exercise
Minimum age
18 Years
Maximum age
55 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Contraindication to exercise, as identified from PARQ(+)

Study design
Purpose of the study
Educational / counselling / training
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Nil
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
Crossover
Other design features
Standardised for prior activity level (24 h)
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Mixed models analysis, using raw parameters (esp. amplitude of temperature response to each form of exercise) or modelled parameters (esp. asymptote and time constant of response), as mentioned in Step 4.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
26/07/2019
Date of last participant enrolment
Anticipated
26/08/2019
Actual
13/10/2020
Date of last data collection
Anticipated
26/09/2019
Actual
15/12/2020
Sample size
Target
4
Accrual to date
Final
6
Recruitment outside Australia
Country [1] 21709 0
New Zealand
State/province [1] 21709 0
Otago

Funding & Sponsors
Funding source category [1] 303360 0
University
Name [1] 303360 0
University of Otago
Country [1] 303360 0
New Zealand
Primary sponsor type
Individual
Name
Prof Jim Cotter
Address
School of Physical Education, Sport and Exercise Science,
University of Otago
PO Box 56
Dunedin 9056
Country
New Zealand
Secondary sponsor category [1] 303390 0
Individual
Name [1] 303390 0
Dr Kate Thomas
Address [1] 303390 0
Department of Surgical Sciences
Dunedin School of Medicine
University of Otago
PO Box 56
Dunedin 9054
Country [1] 303390 0
New Zealand
Other collaborator category [1] 280866 0
Individual
Name [1] 280866 0
Dr Ashley Akerman
Address [1] 280866 0
Montpetit Hall,
University of Ottawa,
125 Universite Pvt,
Ottawa,
Ontario K1N 6N5,
Canada
Country [1] 280866 0
Canada

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 303890 0
University of Otago Human Research Ethics Committee (Health)
Ethics committee address [1] 303890 0
University of Otago
PO Box 56
Dunedin 9056
Ethics committee country [1] 303890 0
New Zealand
Date submitted for ethics approval [1] 303890 0
06/05/2019
Approval date [1] 303890 0
21/05/2019
Ethics approval number [1] 303890 0
H19/056

Summary
Brief summary
This study is the first of two approved within this ethics application. This is a pilot study, aimed at determining the muscle, core and skin temperature responses arising from resistance and high-intensity interval exercise. This information is necessary to then inform the main study, specifically to know how what temperatures are elicited and therefore how to prevent such rises occurring during exercise.
Trial website
Nil
Trial related presentations / publications
N/A
Public notes
This is a pilot study, but has become increasingly important as we realise that the muscle temperature responses to different forms of high intensity exercise appear to be mostly unknown. We are interested in the role that muscle temperature has in driving exercise adaptations, so this pilot study is an important part of that research.

Contacts
Principal investigator
Name 95142 0
Prof Jim Cotter
Address 95142 0
School of Physical Education, Sport and Exercise Science
University of Otago
PO Box 56
Dunedin 9056
Country 95142 0
New Zealand
Phone 95142 0
+64 3 479 9109
Fax 95142 0
+64 3 479 8309
Email 95142 0
[email protected]
Contact person for public queries
Name 95143 0
Prof Jim Cotter
Address 95143 0
School of Physical Education, Sport and Exercise Science
University of Otago
PO Box 56
Dunedin 9056
Country 95143 0
New Zealand
Phone 95143 0
+64 3 479 9109
Fax 95143 0
+64 3 479 8309
Email 95143 0
[email protected]
Contact person for scientific queries
Name 95144 0
Prof Jim Cotter
Address 95144 0
School of Physical Education, Sport and Exercise Science
University of Otago
PO Box 56
Dunedin 9056
Country 95144 0
New Zealand
Phone 95144 0
+64 3 479 9109
Fax 95144 0
+64 3 479 8309
Email 95144 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Pilot trial, and small sample size, so difficult to protect individual confidentiality if shared.


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.