Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12618001765213
Ethics application status
Approved
Date submitted
9/10/2018
Date registered
26/10/2018
Date last updated
21/02/2020
Date data sharing statement initially provided
26/10/2018
Date results information initially provided
21/02/2020
Type of registration
Retrospectively registered

Titles & IDs
Public title
Optimising the exercise experience to facilitate healthy food choices: the role of exercise format and exercise instructors' communication style
Scientific title
Optimising the exercise experience to facilitate healthy food choices: the role of high-intensity intermittent exercise and basic psychological need-support
Secondary ID [1] 296142 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Metabolic-related disease 309729 0
Physical inactivity 310188 0
Condition category
Condition code
Diet and Nutrition 308538 308538 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Using a mixed-subjects yoked 2 (need-support) x 2 (exercise format) factorial design, participants will be allocated to one of two conditions: need-support or no need-support. Within each condition, participants will complete two types of exercise on separate visits: high-intensity intermittent exercise and moderate-intensity continuous exercise.

Need-support will be provided to participants randomised to the support group through the experimenter who holds a bachelor's degree with Honours and has experience conducting research experiments which involve psychological manipulations to the delivery of exercise (e.g., Beer et al., 2017, Medicine & Science in Sports & Exercise, 49, 10, 2110-2118). Training in delivery of need-support has also been provided by members of the research team who are well-versed in the field of exercise motivation (which includes delivery of need-supportive exercise conditions). For example, autonomy-support will be facilitated by providing clear rationales and benefits of the particular type of exercise, acknowledging the feelings of participants towards the exercise, offering choices where possible, such as of the music accompaniment and the order in which participants complete the two exercise conditions (i.e., whether they complete the moderate-intensity continuous exercise or high-intensity intermittent exercise session first) , and using language which is indicative of choice (e.g., “you’re in charge today”). Competence will be supported by providing clear instructions and expectations, offering positive feedback, guidance, and support, and encouraging goal setting. Relatedness will be provided by interacting with warmth and care, offering empathy where appropriate, and displaying appreciation and concern for participants’ well-being. To ensure fidelity of the need-support delivery, participants will complete a questionnaire to assess the instructor's delivery of need-support. Additionally, a modified version of this questionnaire will be completed by two independent observers, who are blind to the experimental conditions, at a number of the experimental sessions.

The high-intensity intermittent exercise will consist of a one-off bout of 30 minutes of cycling alternating very high-intensity efforts performed at a ratio of 1:4 (15 s at a power output equivalent to ~170% peak oxygen consumption; VO2peak) with an active recovery period (60 s at a power output of ~32% VO2peak) between efforts. All sessions will be directly supervised with heart rate and power output monitored to ensure adherence to the prescribed workload.

Following the exercise bout, participants will be provided with an ad libitum test meal to assess post-exercise energy intake. Details of this meal are provided in section 4 (Primary outcome 1).
Intervention code [1] 312471 0
Behaviour
Comparator / control treatment
Participants randomised to the no-support condition will not receive intentional support of autonomy, competence, and relatedness; however, no attempts will be made to purposely undermine participants’ experiences (i.e., participants in the no-support condition will receive ‘typical’ exercise class instructions). That is, instructions will be presented as matter-of-fact in order to create a neutral exercise condition (i.e., not need-supportive or controlling. For instance, participants will not experience choices over their exercise session; however, they will also not be aware that other participants were offered aspects of choice.

The moderate-intensity continuous exercise will consist of a one-off bout of 30 minutes of cycling performed at an intensity equivalent to 60% VO2peak. All sessions will be directly supervised with heart rate and power output monitored to ensure adherence to the prescribed workload.
Control group
Active

Outcomes
Primary outcome [1] 307515 0
Post-exercise energy intake will be assessed using a laboratory test meal consisting of products of known and differing macronutrient composition, including an assortment of typical breakfast foods and treats such as bread, spreads, cereal, milk, fruit, muffins, and biscuits. All food provided will be weighed before participants’ arrival and re-weighed after consumption. In addition to energy intake at the immediate post-exercise meal, food intake will also be measured in the laboratory during the subsequent three hours, during which participants will have free-access to a number of typical snack items (e.g., fruit, chocolate, unsalted popcorn, salted chips/crisps).
Timepoint [1] 307515 0
Post-exercise
Secondary outcome [1] 352154 0
Feelings of appetite will be assessed using a validated visual analogue scale. This requires participants to indicate their feelings of hunger along a 10 cm line.
Timepoint [1] 352154 0
Immediately pre-exercise, immediately post-exercise, and postprandial (approximately 40 minutes post-exercise).
Secondary outcome [2] 352155 0
Blood glucose
Timepoint [2] 352155 0
Immediately pre- and post-exercise
Secondary outcome [3] 352157 0
Perceptions of psychological experiences during exercise (i.e., a composite outcome of enjoyment, choice, tension, effort, relatedness, value, and competence) will be assessed by the Intrinsic Motivation Inventory (Plant & Ryan, 1985, Journal of Personality, 53, 3, 435-449)
Timepoint [3] 352157 0
Immediately post-exercise
Secondary outcome [4] 353207 0
Feelings of appetite will be assessed using a validated visual analogue scale. This requires participants to indicate their feelings of fullness along a 10 cm line.
Timepoint [4] 353207 0
Immediately pre-exercise, immediately post-exercise, and postprandial (approximately 40 minutes post-exercise).
Secondary outcome [5] 353208 0
Feelings of appetite will be assessed using a validated visual analogue scale. This requires participants to indicate their desire to eat along a 10 cm line.
Timepoint [5] 353208 0
Immediately pre-exercise, immediately post-exercise, and postprandial (approximately 40 minutes post-exercise).
Secondary outcome [6] 353209 0
Feelings of appetite will be assessed using a validated visual analogue scale. This required participants to indicate their perceived prospective food consumption along a 10 cm line.
Timepoint [6] 353209 0
Immediately pre-exercise, immediately post-exercise, and postprandial (approximately 40 minutes post-exercise).
Secondary outcome [7] 353210 0
Blood lactate
Timepoint [7] 353210 0
Immediately pre-and post-exercise
Secondary outcome [8] 353211 0
Plasma acylated ghrelin will be measured using a commercially available assay kit (Milliplex Gut Hormone Panel).
Timepoint [8] 353211 0
Immediately pre- and post-exercise

Eligibility
Key inclusion criteria
Participants will be eligible for participation if they are aged between 18 and 40 years and physically inactive, defined as performing less than 75 minutes of moderate to vigorous physical activity per week.
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
- History of medical conditions such as diabetes, hyperlipidaemia
- History of eating disorders known to affect appetite or restrained eaters (measured as scoring above 3.5 on the Dutch Eating Behaviour Questionnaire)
- Diet status which may interfere with food intake (e.g., on a weight-loss diet)
- Currently taking medication which could interfere with energy intake, appetite, or exercise
- Any known food allergies or dietary requirements (e.g., vegan)
- Injury or condition preventing exercise

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)
Allocation nor concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Following the familiarisation session, participants will be pair-matched based on key physical characteristics (sex, age, fitness, body mass, and height). Within each pair, participants will be randomly allocated to the support or no-support group using a random number generator software.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Factorial
Other design features
Participants will be blinded to the purpose of the study (i.e., to assess the effect of various exercise conditions on post-exercise appetite and food intake). Additionally, participants will be blinded to their allocation to a support or no-support group, and instead informed that the purpose of the study is to investigate the effects of high-intensity intermittent exercise and moderate-intensity continuous exercise on physiological and psychological markers of stress.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Statistical analyses will be conducted using SPSS software package for Windows, with statistical significance being accepted at an alpha level of p < 0.05. The effect of exercise format and need-support on energy intake throughout the observation period will be assessed using two-way (condition x trial) ANOVA. Secondary outcomes such as perceived, appetite, appetite-related blood variables and psychological experiences during exercise (i.e., enjoyment, effort, relatedness, value, and competence) will be assessed using two (condition x trial) or three-way (condition x trial x time) ANOVAs as appropriate.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
27/09/2018
Date of last participant enrolment
Anticipated
22/05/2019
Actual
9/07/2019
Date of last data collection
Anticipated
31/05/2019
Actual
18/07/2019
Sample size
Target
36
Accrual to date
Final
40
Recruitment in Australia
Recruitment state(s)
WA

Funding & Sponsors
Funding source category [1] 300726 0
University
Name [1] 300726 0
The University of Western Australia
Country [1] 300726 0
Australia
Primary sponsor type
Individual
Name
Dr Kym Guelfi
Address
The University of Western Australia
School of Human Sciences
35 Stirling Highway
Crawley, WA, 6009
Country
Australia
Secondary sponsor category [1] 300267 0
None
Name [1] 300267 0
Address [1] 300267 0
Country [1] 300267 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 301508 0
The University of Western Australia Human Research Ethics Committee
Ethics committee address [1] 301508 0
The University of Western Australia
35 Stirling Highway
Crawley, WA, 6009
Ethics committee country [1] 301508 0
Australia
Date submitted for ethics approval [1] 301508 0
19/06/2018
Approval date [1] 301508 0
17/09/2018
Ethics approval number [1] 301508 0
RA/4/20/4642

Summary
Brief summary
It is well-established that exercise is associated with a variety of physical and psychological benefits; however, certain post-exercise behaviours, such as consuming excess or unhealthy foods in the aftermath of an exercise session, may counteract some of these benefits. The effect of exercise on food consumption appears to be influenced by both exercise format (e.g., overall intensity and structure of exercise) as well as psychological experiences during exercise. In relation to exercise format, it has been shown that high-intensity intermittent exercise, relative to traditional exercise performed at a moderate-intensity, suppresses appetite and energy intake at the post-exercise period. As for psychological experiences of exercise, it appears that more autonomously motivated individuals may be less likely to endorse the use of food rewards post-exercise. Despite this evidence, numerous issues with this relationship remain unresolved. For instance, no previous work has explored the interactive effects of exercise format and psychological experiences during exercise on subsequent food choices. As such, the aim of this research is to examine which exercise conditions, both in terms of the format and psychological experiences of exercise, have the strongest influence on post-exercise appetite and food intake.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 87238 0
Dr Kym Guelfi
Address 87238 0
The University of Western Australia
School of Human Sciences
35 Stirling Highway
Crawley, WA, 6009
Country 87238 0
Australia
Phone 87238 0
+61864882602
Fax 87238 0
Email 87238 0
[email protected]
Contact person for public queries
Name 87239 0
Miss Natalya Beer
Address 87239 0
The University of Western Australia
School of Human Sciences
35 Stirling Highway
Crawley, WA, 6009
Country 87239 0
Australia
Phone 87239 0
+61864882602
Fax 87239 0
Email 87239 0
[email protected]
Contact person for scientific queries
Name 87240 0
Miss Natalya Beer
Address 87240 0
The University of Western Australia
School of Human Sciences
35 Stirling Highway
Crawley, WA, 6009
Country 87240 0
Australia
Phone 87240 0
+61864882602
Fax 87240 0
Email 87240 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
Should data be requested at the time of journal submission, de-identified data may be provided.


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
7Ethical approval    376045-(Uploaded-25-10-2018-17-50-27)-Study-related document.pdf



Results publications and other study-related documents

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No additional documents have been identified.