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Trial registered on ANZCTR


Registration number
ACTRN12621001007820
Ethics application status
Approved
Date submitted
16/11/2020
Date registered
30/07/2021
Date last updated
30/07/2021
Date data sharing statement initially provided
30/07/2021
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effect of a short-term potato-enriched diet on muscle protein synthesis in recreationally active men
Scientific title
The effect of a short-term potato-enriched diet on muscle accretion and substrate metabolism adaptations in recreationally active men
Secondary ID [1] 300323 0
None
Universal Trial Number (UTN)
U1111-1247-0003
Trial acronym
Linked study record
No linked study record

Health condition
Health condition(s) or problem(s) studied:
Skeletal muscle growth 315933 0
Condition category
Condition code
Diet and Nutrition 314203 314203 0 0
Other diet and nutrition disorders
Musculoskeletal 314204 314204 0 0
Normal musculoskeletal and cartilage development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Approximately two weeks before the commencement of the exercise-nutrition intervention,
participants will undertake a 1-repetition maximum (1RM) testing on the leg-press machine.
Participants will firstly be demonstrated proper lifting technique by research staff prior to engaging in 1RM testing. Participants will warm up at a self-selected load for each movement
until reaching a rating of perceived exertion (RPE) of ~ 8 using a Borg Category Ratio 10 scale, for a single repetition. Thereafter, a series of single repetitions will be attempted, with 5 min recovery, until the maximal load possible for one repetition with full range of motion
is determined. For the leg press, full range of motion will be established as beginning with the knees in full extension (0°), performing 90° of knee flexion, and returning to full
knee extension. Participants will then be stratified and matched for one repetition maximum leg press strength (1-RM) and muscle thickness (measured via Ultrasound) into the following two dietary groups (n=10/group) matched for dietary energy and protein intake:
1) Vegan: Potato-enriched, non-animal protein (1.5-1.7 g/kg body mass [BM] of protein per day, all protein derived from non-animal based sources)
2) Omnivore: Animal-protein (1.5-1.7g/kg BM of protein per day, most protein derived from animal-based sources)

The nutritional intervention will last a total of 14 full days. During this time, total energy (caloric) intake will be based on an energy availability of 45 kcal/kg Fat Free Mass per day (as based on previously published work: PMID 28855275) to ensure at energy balance state. Of this total caloric intake, participants in both groups will consume ~1.5-1.7 g/kg body mass of protein per day, ~3.5-4.0 g/kg body mass of carbohydrate per day and 1.0-1.2 g/kg body mass of fat per day. Menu construction for both dietary groups will be undertaken by Accredited Practicing Dieticians at the Nutrition and Dietetics facility at Swinburne University. Preparation and packaging of all meals and snacks will be undertaken within the kitchen facilities in room 2.10 (Building SPW) at Swinburne University. This room is approved for meal preparation within the Bachelor of Nutrition and Dietetics degree. All meals will be prepared by a professional chef and Accredited Practicing Dietitian. Every three days participants will meet with the dietician to receive new food parcels and monitor adherence to the previous days’ diet. Menus for each diet will provide three meals per day as well as “snack baskets” and post-exercise supplementation. Participants assigned to consume animal protein will consume animal-derived protein snack sources (i.e., eggs, cheese, yoghurt) with 0% protein derived from potato sources. In contrast, participants consuming the potato-based, non-animal protein diet will consume 50% of their protein from potato-based sources comprising practical, whole-food potato-based items. Food records will be kept daily by participants throughout the 14-day intervention using mobile phone applications Easy Diet Diary (Xyris Software Pty Ltd, Australia, for participants with iPhones®, Apple Inc., USA) and MyFitnessPal (MyFitnessPal Inc., USA, for participants with Android-based devices, Google Inc., USA). All dietary intake data will be analysed using FoodWorks (Xyris Software Pty Ltd, Australia) to ensure the same food database is used for all analysis. Diet records will be analysed for energy, protein, carbohydrate, and fat to provide a daily average for the entire 14-day intervention.

Participants will commence supervised concurrent (i.e.: combined) exercise on Day 2 of the intervention, comprising resistance and endurance exercise on alternating days. All resistance exercise sessions will be performed in the School of Exercise and Sports Sciences gym (Building SPW, Ground Level) while all endurance sessions will be performed on a stationary ergometer in the Exercise and Sports Sciences laboratory (Building SPW, Level 1); both at Swinburne University. In total, participants will undertake six resistance exercise training sessions and six endurance exercise sessions, with each of these exercise sessions lasting approximately 40 minutes in duration. All exercise sessions will be co-ordinated by university staff members who possess experience in postgraduate exercise and sport science research and Certificate 3 and 4 in Fitness. Resistance training will consist of whole body exercises with a focus on the leg press, knee extension and bench press movements (all machine-based exercise), with these exercises to be performed at an intensity of ~60–80% of 1-Reptition Maximum. All exercises will be separated by a 3-min between-set recovery period. Endurance cycle training will be performed on Lode cycle ergometers and consist of a mixture of moderate-intensity continuous training at ~60-75% of heart rate maximum and high-intensity interval training at 100% heart rate maximum. Short, active recovery periods (1-3 minutes) will separate each ‘work’ bout.

The method of allocation to be used in study will be an alternating allocation.
Intervention code [1] 318962 0
Lifestyle
Comparator / control treatment
Omnivore Diet Group
- Based mostly on typical nutritional guidelines where most protein will be derived from animal based food sources
- Carbohydrate and fat intake will be within the acceptable macro nutrient distribution range (45-65% and 20-35%), respectively
- Carbohydrate and fat intakes will be the same between the experimental (vegan) and control (omnivore) groups.
- Protein above current recommended intake at 1.5-1.7g/kg body mass
- Protein and total caloric intake will be matched to the experimental (vegan) group
Control group
Active

Outcomes
Primary outcome [1] 325577 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] 325577 0
14-days post-dietary intervention
Secondary outcome [1] 388430 0
Rates of synthesis of individual skeletal muscle proteins 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] 388430 0
14-days post-dietary intervention
Secondary outcome [2] 398088 0
Rates of breakdown of individual skeletal muscle proteins 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 [2] 398088 0
14-days post-dietary intervention
Secondary outcome [3] 398089 0
Abundance of individual skeletal muscle proteins 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 [3] 398089 0
14-days post-dietary intervention

Eligibility
Key inclusion criteria
- Male
- Aged between 20 and 30 years
- BMI between 18.5 and 24.9 kg/m2
- Strictly omnivorous (i.e.: habitually consumed meat-based products as part of their diet) for more than 12 months prior to the study
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
- Vegetarians or vegans

Study design
Purpose of the study
Treatment
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
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
Recruiting
Date of first participant enrolment
Anticipated
Actual
13/11/2020
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
1/10/2021
Actual
Sample size
Target
16
Accrual to date
1
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment postcode(s) [1] 32001 0
3122 - Hawthorn
Recruitment postcode(s) [2] 32002 0
3123 - Hawthorn East
Recruitment postcode(s) [3] 32003 0
3124 - Camberwell
Recruitment postcode(s) [4] 32004 0
3144 - Malvern

Funding & Sponsors
Funding source category [1] 304748 0
Commercial sector/Industry
Name [1] 304748 0
The Alliance for Potato Research and Education
Country [1] 304748 0
United States of America
Primary sponsor type
University
Name
Swinburne University
Address
John Street, Hawthorn,
Victoria,
3122
Country
Australia
Secondary sponsor category [1] 305062 0
None
Name [1] 305062 0
Address [1] 305062 0
Country [1] 305062 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 305168 0
Swinburne Human Research Ethics Committee
Ethics committee address [1] 305168 0
John Street,
Hawthorn,
Victoria, 3122
Ethics committee country [1] 305168 0
Australia
Date submitted for ethics approval [1] 305168 0
04/09/2020
Approval date [1] 305168 0
06/11/2020
Ethics approval number [1] 305168 0
20204221-5482

Summary
Brief summary
The World Health Organization (WHO) recommends performing both strength/power (resistance-based exercise) and endurance activities (walking, running, cycling, swimming) for wellbeing. Appropriate nutritional support is essential to maximize the beneficial effects of any training program. In this regard, it is well accepted that the ingestion of high quality animal protein (meat and dairy products) as well as specially formulated high-protein bars and drinks have an additive effect in optimizing training-induced increases in muscle growth and strength following resistance-based exercise. In contrast, endurance-based training adaptations are amplified by the ingestion of carbohydrate-rich foods/supplements that rapidly restore muscle and liver glycogen stores and support skeletal muscle remodelling (i.e., mitochondrial biogenesis). Despite their benefits, current trends in consumer preferences driven by environmental factors, health benefits and/ or ethical reasons have brought to the forefront a need to advance knowledge of alternate food and beverage sources beyond conventional products. Vegan dietary practices are characterized by the avoidance of animal-based food ingredients, including dairy products and eggs. Such diets have been associated with a reduced risk of cardiovascular disease and type 2 diabetes. The proportion of individuals choosing to follow a vegan diet has increased in many industrialized nations and trend analysis predicts that their influence on the food sector will continue to grow. While numerous studies have investigated the postprandial muscle protein synthesis response to the ingestion of animal-based (dairy and meat) protein sources, little is known about the muscle protein synthesis response to plant-based proteins. To date, the anabolic properties of such plant-based proteins have only been investigated in limited protein sources. The primary aim of this project is to determine the effect of a non-animal protein diet on rates of muscle protein synthesis consumed during a short-term combined (‘concurrent’) resistance and endurance training program in healthy young males. It is hypothesized that a short-term, non-animal diet in combination with concurrent exercise will increase the synthesis and abundance of individual muscle proteins involved in the responses to both strength- and endurance-based exercise.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 99470 0
Dr Donny Camera
Address 99470 0
Swinburne University
Room SPW224
Mail H21
PO Box 218 Hawthorn
Vic, 3122
Country 99470 0
Australia
Phone 99470 0
+61 392145233
Fax 99470 0
Email 99470 0
[email protected]
Contact person for public queries
Name 99471 0
Donny Camera
Address 99471 0
Swinburne University
Room SPW224
Mail H21
PO Box 218 Hawthorn
Vic, 3122
Country 99471 0
Australia
Phone 99471 0
+61 392145233
Fax 99471 0
Email 99471 0
[email protected]
Contact person for scientific queries
Name 99472 0
Donny Camera
Address 99472 0
Swinburne University
Room SPW224
Mail H21
PO Box 218 Hawthorn
Vic, 3122
Country 99472 0
Australia
Phone 99472 0
+61 392145233
Fax 99472 0
Email 99472 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


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.