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Trial registered on ANZCTR


Registration number
ACTRN12613001044718
Ethics application status
Approved
Date submitted
27/08/2013
Date registered
19/09/2013
Date last updated
19/09/2013
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effect of resistance exercise and increasing doses of protein ingestion on muscle protein synthesis during acute energy deprivation
Scientific title
The effect of resistance exercise and increasing doses of protein ingestion on myofibrillar protein synthesis in young, healthy, trained males and females
Secondary ID [1] 283022 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Muscle mass loss prevention 289854 0
Condition category
Condition code
Musculoskeletal 290212 290212 0 0
Normal musculoskeletal and cartilage development and function
Diet and Nutrition 290213 290213 0 0
Other diet and nutrition disorders
Metabolic and Endocrine 290214 290214 0 0
Normal metabolism and endocrine development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Trial B - Subjects will arrived after 5 days of controlled energy deficit diet (30 kcal/kg fat free mass (FFM) per day). All diets will be prepared by a specialized team and provided as pre-packaged meals, adherence to diet will be monitored via a check-list filled by participants. Tracer intravenous administration (L-ring-13C6 Phe) will start upon subject arrival and continue during 3 h for measurement of resting fractional synthetic rate (FSR) in calorie restriction diet intervention. Thereafter, subjects will undertake a resistance exercise bout (leg press, 6 sets, 8 reps, 80% 1 repetition maximum, 3 min rest between sets). In this trial subjects will ingest a 0 (placebo), 15 or 30 g of Whey Protein in liquied form (500 ml) immediately after the exercise and FSR will be measured between 1 and 4 h post exercise for determining the muscle anabolic response to resistance exercise after 5 days of a calorie restriction diet.

Trials C & D -Subjects will arrived after 5 days of controlled energy deficit diet (30 kcal/kg fat free mass (FFM) per day). Ring-13C6 Phe infusion will begin prior to resistance exercise. At the completion of exercise, subjects will ingest either 0 (placebo), 15 or 30 g of Whey Protein in liquid form (500 ml). FSR will be measured between 1 and 4 h post exercise for determining the response after exercise to either 0, 15 or 30g of WP after 5 days of a calorie restriction diet.

The difference between trial B and C & D is that trial B incorporates measurement of resting FSR prior to exercise, whereas trial C and D do not incorporate a period of resting FSR measurement. After exercise all the trials are essentially the same but the drinks will be randomized to contain either 0, 15 or 30 g of protein.

All participants will undertake all trials. The washout period between trials is 9 days.
Intervention code [1] 287742 0
Lifestyle
Comparator / control treatment
Trial A – Subjects will arrive after 5 days of controlled energy balanced diet (45 kcal/kg FFM per day). All diets will be prepared by a specialized team and provided as pre-packaged meals, adherence to diet will be monitored via a check-list filled by participants. Tracer intravenous administration (L-ring-13C6 Phe) will start upon subject arrival and continue during 3 h for measurement of resting fractional synthetic rate (FSR) under energy balance. This trial incorporates no resistance exercise intervention or protein intake.
Control group
Active

Outcomes
Primary outcome [1] 290326 0
myofibrillar fractional synthetic rate (FSR). Measured using primed constant intravenous infusion of ring-[13C6]phenylalanine. FSR is determined as the difference of tracer enrichment in myofibrillar protein between two subsequent skeletal muscle biopsies.
Timepoint [1] 290326 0
Two muscle biopsies taken 3 h apart for each treatment. Resting energy balance (trial A) and energy deficit (trial B): 0 and 3 h after initiation of tracer infusion.
Exercise (trials B,C and D): 1 and 4 h after finalization of exercise/ingestion of protein or placebo drink.
Secondary outcome [1] 304307 0
Intracellular signalling measured through western blotting of cytoplasmic proteins using specific primary antibodies.
Timepoint [1] 304307 0
Resting energy balance, 3 h; Resting energy deficit (ED), 3 h; ED + Resistance exercise (REX) + placebo (PL), 1 h; ED + REX + PL, 4 h; ED + REX + 15 g protein, 1 h; ED + REX + 15 g protein, 4 h; ED + REX + 30 g protein, 1 h; ED + REX + 30 g protein, 4 h.
Secondary outcome [2] 304308 0
mRNA content for specific genes, measured using real time PCR
Timepoint [2] 304308 0
Resting energy balance, 3 h; Resting energy deficit (ED), 3 h; ED + Resistance exercise (REX) + placebo (PL), 1 h; ED + REX + PL, 4 h; ED + REX + 15 g protein, 1 h; ED + REX + 15 g protein, 4 h; ED + REX + 30 g protein, 1 h; ED + REX + 30 g protein, 4 h.

Eligibility
Key inclusion criteria
All subjects must comply with the following inclusion criteria:
1) Healthy and physically active (as determined by medical and activity questionnaire)
2) Having given informed consent
Minimum age
18 Years
Maximum age
35 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Subjects representing one or more of the following criteria are excluded from participation in the study.
1) Exhibiting health risk factors as identified on the health screening questionnaire
2) Having any identified metabolic or intestinal disorders
3) Tobacco use
4) Aspirin use in the four days prior to the experimental trial
5) Consumption of prescription medications or any performance enhancing agent
6) Inability to endure the strenuous exercise bouts e.g. injuries
7) Alcohol intake during the 48 hours prior to each of the testing days
8) Currently participating or having participated in another clinical trial during the last 4 weeks prior to the beginning of this study
9) Have given blood in the last three weeks
10) Verbal confirmation that they have used a substance on the WADA banned list within the last year

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)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Type of endpoint/s
Statistical methods / analysis

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 in Australia
Recruitment state(s)
ACT

Funding & Sponsors
Funding source category [1] 287843 0
Government body
Name [1] 287843 0
Australian Research Council
Country [1] 287843 0
Australia
Primary sponsor type
University
Name
RMIT University
Address
McKimmies and Plenty Rd
Bundoora 3083
Victoria
Country
Australia
Secondary sponsor category [1] 286571 0
Government body
Name [1] 286571 0
Australian Institute of Sport
Address [1] 286571 0
Leverrier Crescent, Bruce ACT 2617, Australia
Country [1] 286571 0
Australia

Ethics approval
Ethics application status
Approved

Summary
Brief summary
Our primary objective is to determine the effect of 5 days of dietary energy restriction (i.e. ~30 vs. the normal energy balance of ~45kcal/kg FFM/day) on muscle myofibrillar fractional synthetic rate (FSR; directly measured muscle protein synthesis) at rest as measured by primed constant infusion of ring-[13C6]phenylalanine.

Our secondary objectives involve examining whether the anabolic stimulus of protein ingestion and resistance exercise will significantly increase FSR (post-exercise FSR). If an exercise plus nutrition intervention rescues the deleterious effect of a hypocaloric diet on muscle FSR this will provide novel and practical information for effective weight management in which fat mass can be reduced without loss of muscle mass.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 42166 0
Prof John A Hawley
Address 42166 0
McKimmies and Plenty Rds
Building 203.3.32
RMIT University
Bundoora
Victoria 3083
AUSTRALIA
Country 42166 0
Australia
Phone 42166 0
61-3-9925 7353
Fax 42166 0
Email 42166 0
john.hawley@rmit.edu.au
Contact person for public queries
Name 42167 0
Prof John A Hawley
Address 42167 0
McKimmies and Plenty Rds
Building 203.3.32
RMIT University
Bundoora
Victoria 3083
AUSTRALIA
Country 42167 0
Australia
Phone 42167 0
61-3-9925 7353
Fax 42167 0
Email 42167 0
john.hawley@rmit.edu.au
Contact person for scientific queries
Name 42168 0
Prof John A Hawley
Address 42168 0
McKimmies and Plenty Rds
Building 203.3.32
RMIT University
Bundoora
Victoria 3083
AUSTRALIA
Country 42168 0
Australia
Phone 42168 0
61-3-9925 7353
Fax 42168 0
Email 42168 0
john.hawley@rmit.edu.au

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No Supporting Document Provided



Results publications and other study-related documents

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