Please note the ANZCTR will be unattended from Friday 24 December 2021 for the holidays. The Registry will re-open on Monday 17 January 2022. Submissions and updates will not be processed during that time.

For new and updated trial submissions, we are processing trials as quickly as possible and appreciate your patience. We recommend submitting your trial for registration at the same time as ethics submission.

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
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Profiling skeletal muscle loss during leg immobilisation and a reduced energy diet
Scientific title
Effect of reduced energy availability on skeletal muscle loss during leg immobilisation in healthy male adults
Secondary ID [1] 292527 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Skeletal muscle atrophy 304175 0
Condition category
Condition code
Musculoskeletal 304234 304234 0 0
Other muscular and skeletal disorders
Injuries and Accidents 304235 304235 0 0
Other injuries and accidents

Study type
Description of intervention(s) / exposure
14 days of limb (leg) immobilisation will be undertaken using a Donjoy X-ACT ROM Universal leg brace worn 24 h per day. This intervention will be combined with a 30% energy restriction over the 14 day immobilisation period. All foods will be provided to participants and supplied by a commercial provider (Lite 'n' easy, Brisbane, Australia). For the seven days prior to knee brace immobilisaton, participants will be provided a diet to achieve expected energy balance as calculated by the Schofield equation with an activity factor of 1.5. Macronutrient contributions will be ~17/66/17% for protein, carbohydrate and fat, respectively; protein will be clamped at 1.4-1.5 g/kg. At the commencement of the immobilisation period, an energy deficit of 30% (based on Schofield equation and activity factor of 1.5) will be implemented by reducing carbohydrate (primarily) and fat intake; protein will remain clamped at 1.4-1.5 g/kg. The resulting macronutrient contributions will be ~23/57/20% for protein, carbohydrate and fat, respectively, Adherence to diet will be monitored via daily food diaries that require participants to check off all foods consumed. Adherence to immobilisation will be monitored through actigraph accelerometers to determine physical activity levels and a unique identifier tape wrapped around to the brace will determine if/when a brace is removed. Muscle biopsies will be obtained on day 0, 3 and 14.
Intervention code [1] 298713 0
Treatment: Other
Intervention code [2] 299233 0
Treatment: Devices
Comparator / control treatment
A control group will be obtained from a prior study conducted in our laboratory that completed the same immobilisation intervention (14 days) in energy balance (Schofield equation with an activity factor of 1.5). The data collection period of the prior study was between 17/10/2016 and 1/7/2017 (ACTRN12616001399482).
Control group

Primary outcome [1] 302875 0
Changes in quadriceps muscle mass quantified by MRI and DEXA scans
Timepoint [1] 302875 0
Baseline (Day 0), and day 14 measurements
Primary outcome [2] 302876 0
Muscle biopsy analysis will be undertaken to better understand RNA/protein changes in muscle tissue samples due to immobilisation induced atrophy in combination with energy restriction. A non-specific global analysis of changes in RNA expression will be conducted.
Timepoint [2] 302876 0
Baseline (day 0), day 3 and day 14
Secondary outcome [1] 337285 0
Change in muscle strength as determined by isotonic testing. 3 repetition maximum load will be measured in the immobilised and non-immobilised legs on a unilateral leg press, and plate loaded leg extension and leg-curl machines.
Timepoint [1] 337285 0
Baseline (pre-immobilisation), and day 15 (one day post-immobilisation)

Key inclusion criteria
Physically active individuals undertaking ~4 exercise sessions per week of moderate-vigorous exercise.
Minimum age
20 Years
Maximum age
40 Years
Can healthy volunteers participate?
Key exclusion criteria
Recent (<6 months) injury requiring immobilsation, medical conditions that would place participants at increased risk during resistance exercise (strength testing), currently taking medications known to affect body composition, dietary allergies, employment requiring physical labour.

Study design
Purpose of the study
Allocation to intervention
Non-randomised 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
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Single group
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
Repeated measures mixed ANOVA and other appropriate analysis of molecular results

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 297095 0
Name [1] 297095 0
Bond University
Address [1] 297095 0
14 University Drive, ROBINA QLD 4226, AUSTRALIA.
Country [1] 297095 0
Primary sponsor type
Bond University
14 University Drive, ROBINA QLD 4226, AUSTRALIA.
Secondary sponsor category [1] 296104 0
Name [1] 296104 0
Address [1] 296104 0
Country [1] 296104 0

Ethics approval
Ethics application status
Ethics committee name [1] 298273 0
Bond University Human Research Ethics Committee
Ethics committee address [1] 298273 0
Bond University
University Drive, Robina
Gold Coast, QLD 4226
Ethics committee country [1] 298273 0
Date submitted for ethics approval [1] 298273 0
Approval date [1] 298273 0
Ethics approval number [1] 298273 0

Brief summary
The nature of training and competition in the majority of popular sports dictates that debilitating injury is not uncommon when individuals engage in high musculoskeletal loading patterns and/or high impact collisions. A consequence of such injuries is that repair and remodelling of tissues and joints often requires significant periods of limb immobilisation. During immobilisation a reduction in the normal mechanical loading of skeletal muscle results in muscle wasting (atrophy).

A challenge for individuals during periods of reduced physical activity (e.g. bed rest) or immobilisation is the management of body composition. The muscle unloading interaction with dietary intake has the capacity to modulate the effects of immobilisation on mechanisms regulating skeletal muscle mass. We (Areta et al. 2014) and others (Pasiakos et al. 2013) have shown that reduced total energy intake (30-40% below energy balance requirements) decreases muscle protein synthesis and results in a loss of fat mass but also muscle mass. However, higher protein intakes (>1.6 g/kg) during energy deficit may attenuate losses in lean mass (Pasiakos et al. 2013), despite an increased expression of genes associated with muscle protein breakdown (Carbone et al. 2013). How these dietary-muscle protein interactions change during periods of immobilisation is unknown.

Decreased energy expenditure from cessation of physical activity with immobilisation necessitates restriction of energy intake to prevent undesirable gains in fat mass. However, whether implementing an energy deficit, despite higher protein intakes, exacerbates muscle wasting experienced during muscle unloading is unknown. Importantly, the effect of an energy deficit on the magnitude of muscle loss and the associated underlying molecular profile during immobilisation is currently unknown.

The aim of this study is to determine changes in inducible gene/protein expression and skeletal muscle mass in the acute (3 d) and early (14 d) immobilisation period while under a moderate (30%) energy restriction with sufficient protein intake (1.4-1.5 g/kg). We will compare the effect of this energy deficit on muscle mass with immobilised participants in energy balance, a study previously completed in our laboratory. We hypothesize that 14 d of limb immobilisation with energy deficit will result in greater losses of total body fat, immobilised limb mass and gene expression for protein breakdown compared to immobilised limbs in energy balance.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 76554 0
Dr Thomas Doering
Address 76554 0
Bond Institute of Health and Sport, Bond University, 2 Promethean Way, Robina, QLD 4226 Australia.
Country 76554 0
Phone 76554 0
+61 7 5595 0178
Fax 76554 0
Email 76554 0
Contact person for public queries
Name 76555 0
Dr Thomas Doering
Address 76555 0
Bond Institute of Health and Sport, Bond University, 2 Promethean Way, Robina, QLD 4226 Australia.
Country 76555 0
Phone 76555 0
+61 7 5595 0178
Fax 76555 0
Email 76555 0
Contact person for scientific queries
Name 76556 0
Dr Thomas Doering
Address 76556 0
Bond Institute of Health and Sport, Bond University, 2 Promethean Way, Robina, QLD 4226 Australia.
Country 76556 0
Phone 76556 0
+61 7 5595 0178
Fax 76556 0
Email 76556 0

No information has been provided regarding IPD availability
Summary results
No Results