Technical difficulties have been reported by some users of the search function and is being investigated by technical staff. Thank you for your patience and apologies for any inconvenience caused.

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
ACTRN12623000072617
Ethics application status
Approved
Date submitted
22/12/2022
Date registered
23/01/2023
Date last updated
23/01/2023
Date data sharing statement initially provided
23/01/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
Muscle protein synthesis responses to a short-term 5:2 intermittent energy restricted diet combined with exercise
Scientific title
Muscle protein synthesis responses to a short-term 5:2 intermittent energy restricted diet combined with exercise in healthy males aged 20 to 30 years.
Secondary ID [1] 308343 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record
ACTRN12621001007820 is a parent study to the current study.

Health condition
Health condition(s) or problem(s) studied:
Lean body mass loss 328133 0
Condition category
Condition code
Musculoskeletal 325184 325184 0 0
Normal musculoskeletal and cartilage development and function
Diet and Nutrition 325185 325185 0 0
Other diet and nutrition disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants will follow an energy restricted, 5:2 intermittent energy restricted diet for 2 weeks (14 days), while undertaking supervised resistance training every second day (7 sessions total).

Diet
The diet will be designed to meet an average of 80% of each participant's weekly energy requirements. This will consist of:

*2, non-consecutive fasting days conducted on non-exercise days, providing approximately 30% of energy requirements and providing 1.6 grams of protein per kilogram of bodyweight. Consumption on these days will be made up of protein-based drinks that will be spread out across 4 even doses during the day (8am, 12pm, 4pm, 8pm). Powders will be provided to participants that contain protein powder and maltodextrin, with the latter added to make up the remaining energy requirements once the protein requirement is met.
*5 non-fasting days. These days will provide 100% of energy requirements and 1.6 grams of protein per kilogram of bodyweight, including protein shakes post-exercise on exercise days and elsewhere during the day on non-fasting days to ensure protein requirements are met. The diet will be administered by an accredited practicing dietitian. All food will be provided to participants, with adherence monitored via participant completed checklists of the food.

Resistance training

Participants will undertake supervised (by a qualified strength and conditioning instructor or personal trainer) lower limb resistance training every second day. This will include 3 sets of 4 different exercises, with participants conducting 8-12 repetitions with weight progressively overloaded each session once participants achieve more than 12 repetitions. As exercises will be machine or dumbbell based, increases will occur based on the next increment of weight available (e.g. 2.5kg for dumbbells, or 2.5-5kg for machine exercises). Leg press increments will be agreed upon by the supervisor and the participant. Exercises will include weighted lunges (forward and back) as well as leg press and leg extension exercises.

Sessions will occur in individual or small group (2-3 participants per instructor) sessions. Rating of perceived exertion (RPE) will be rated on a 10 point scale at the end of each session. Effort will be standardised by asking participants to complete each set until they feel they could only complete 1-2 repetitions more, with the last set to be completed until failure. These sessions will last approximately 45 minutes, and all exercise sessions will be recorded for each participant via a work out log.
Intervention code [1] 324790 0
Lifestyle
Comparator / control treatment
The comparator group will be an energy balanced (i.e. provided energy to meet their daily energy requirements), protein matched group undertaking the same resistance training protocol.
Control group
Active

Outcomes
Primary outcome [1] 333061 0
Rates of myofibrillar protein synthesis from resting/ basal fractional synthetic rate to the end of post-experimental period as measured by deuterium oxide (D2O) uptake into skeletal muscle and calculated by using mass isotopomer distribution analysis based on previous work (PMID: 28855275).
Timepoint [1] 333061 0
14-days post-dietary intervention commencement.
Secondary outcome [1] 415695 0
Changes in 1 repetition maximum (1-RM) strength assessed using leg press and leg extension exercises.
Timepoint [1] 415695 0
Baseline and end of intervention (day 14 post dietary intervention commencement)
Secondary outcome [2] 417271 0
Changes in VO2 max assessed using an incremental cycle ergometer test.
Timepoint [2] 417271 0
Baseline and end of intervention (day 14 post dietary intervention commencement).

Eligibility
Key inclusion criteria
- Male
- Aged between 20 and 30 years
- BMI between 18.5 and 24.9 kg/m2

Minimum age
20 Years
Maximum age
30 Years
Sex
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
- Smokers (casual or habitual)
- Participating in structured exercise training (> 2 days/ week) for the 6 months prior to the study
- Taking medications that can alter muscle metabolism and growth
- Presence of metabolic or anabolic-related clinical conditions

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A simple randomisation technique using a computerised random sequence generator will be used to allocate participants to groups.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
Sample size has been calculated on an expected increase of 0.53 %/day in the primary outcome measure of rates of myofibrillar protein synthesis from resting/ basal fractional synthetic rate to the end of post-experimental period (i.e. after 14-days nutritional intervention) from studies that have used deuterium oxide as an amino acid labelling method in human skeletal muscle [PMIDs: 28855275, 25650305, 26169934]. With a standard deviation of 0.35 %/day, a minimum number of 8 participants in each group (allowing for a 15% dropout) is required to detect a statistical difference (power equals 90%, alpha less than 0.05).

Recruitment
Recruitment status
Not yet 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] 312585 0
Commercial sector/Industry
Name [1] 312585 0
The Alliance for Potato Research and Education
Country [1] 312585 0
United States of America
Funding source category [2] 312618 0
University
Name [2] 312618 0
Swinburne University
Country [2] 312618 0
Australia
Primary sponsor type
University
Name
Swinburne University
Address
John Street,
Hawthorn,
Victoria, 3122
Country
Australia
Secondary sponsor category [1] 314229 0
None
Name [1] 314229 0
Address [1] 314229 0
Country [1] 314229 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311912 0
Swinburne Human Research Ethics Committee
Ethics committee address [1] 311912 0
John Street,
Hawthorn,
Victoria, 3122
Ethics committee country [1] 311912 0
Australia
Date submitted for ethics approval [1] 311912 0
04/09/2020
Approval date [1] 311912 0
08/11/2022
Ethics approval number [1] 311912 0

Summary
Brief summary
This study will look at the effects on muscle protein synthesis (rates of building new muscle) when people undertake resistance training while consuming 2 different types of diet for 2 weeks. One will restrict energy intake using an intermittent fasting restriction (2 days per week of severe dietary restriction), and the other will meet individual energy requirements. Generally, energy restriction results in lower muscle protein synthesis, however energy restriction is usually undertaken every day, rather than over 2 days per week. It is hypothesised that that rates of muscle protein synthesis rates will not be significantly different between groups.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 122814 0
Dr Stephen Keenan
Address 122814 0
Swinburne University
Room SPW224
Mail H21
PO Box 218 Hawthorn
Vic, 3122
Country 122814 0
Australia
Phone 122814 0
+61 3 92145383
Fax 122814 0
Email 122814 0
skeenan@swin.edu.au
Contact person for public queries
Name 122815 0
Dr Stephen Keenan
Address 122815 0
Swinburne University
Room SPW224
Mail H21
PO Box 218 Hawthorn
Vic, 3122
Country 122815 0
Australia
Phone 122815 0
+61 3 92145383
Fax 122815 0
Email 122815 0
skeenan@swin.edu.au
Contact person for scientific queries
Name 122816 0
Dr Stephen Keenan
Address 122816 0
Swinburne University
Room SPW224
Mail H21
PO Box 218 Hawthorn
Vic, 3122
Country 122816 0
Australia
Phone 122816 0
+61 3 92145383
Fax 122816 0
Email 122816 0
skeenan@swin.edu.au

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.