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Trial registered on ANZCTR


Registration number
ACTRN12622000924752
Ethics application status
Approved
Date submitted
22/03/2022
Date registered
28/06/2022
Date last updated
9/05/2024
Date data sharing statement initially provided
28/06/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
Effects of rapid weight loss on strength capabilities of powerlifters
Scientific title
Assessment of the effect of a rapid weight loss by approximately of 5% body mass on maximal strength capacity levels in powerlifters
Secondary ID [1] 306735 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
body mass reduction 325725 0
strength training 325726 0
low muscle mass 325727 0
nutritional status 325728 0
low mood 325729 0
Condition category
Condition code
Diet and Nutrition 323069 323069 0 0
Other diet and nutrition disorders
Metabolic and Endocrine 323070 323070 0 0
Normal metabolism and endocrine development and function
Mental Health 323071 323071 0 0
Other mental health disorders
Musculoskeletal 323299 323299 0 0
Other muscular and skeletal disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Implementation of a ketogenic diet, low-fiber diet, and dehydration to induce a rapid loss of 5% of body mass as well as application of a recuperation process between weigh-ins and simulated competitions consisting of proper hydration and adequate carbohydrate supply.

The following procedures/activities will be performed:
- During the first week of the experiment, each athlete will reduce their usual training volume by 50% with training intensity maintained. Each athlete will perform 2 training units (participants will undergo a 1-hour exercise block consisting of their usual training regimen on days 1 and 3). On days 4-6, each athlete's eating habits will be assessed.
- On day 7 at 9:00 am, baseline anthropometric measurements will be taken in the gym where the participants regularly train. Following the anthropometric measurements, athletes will complete mental status and lifestyle questionnaires. Between the anthropometric measurements and the start of the simulated powerlifting competition, there will be a 2-hour break. At 11:00 am a simulated competition in powerlifting triathlon will begin, during which the maximum strength of athletes will be measured; participants will undergo a powerlifting component including the squat, bench press, and deadlift.
- On days 10-13, athletes in group one will follow a dietary strategy leading to a 5% rapid weight loss (nothing will occur if participants are not able to achieve the expected rapid 5% weight loss).
- On day 10, there will be an additional single training - the training will be the same as day 3 of the study.
- On day 14 at 9:00 am, control anthropometric measurements will be taken in the gym where the participants regularly train. Following the anthropometric measurements, athletes will complete UWIST Mood Adjective Check List in the Polish adaptation by Gorynska (2005). Between the anthropometric measurements and the start of the simulated powerlifting competition, there will be a 2-hour break. At 11:00 am a simulated competition in powerlifting competition will begin, during which the maximum strength of athletes will be measured.

All the procedures will be conducted by the main investigator Arkadiusz Matras (dietician) and will be supported by Michal Czapla (dietician and paramedic). The Simulated competitions will be conducted in accordance with the rules of the IPF federation. The composition of the ketogenic and low-fiber diet included a detailed list of meals prepared in the form of an Individualized Nutrition Program (INP), which included a dietary schedule of meals including their composition expressed in grams and items, the caloric content of meals, macronutrient profile (proteins, carbohydrates, fats, and fiber), and meal consumption times.

Participants will receive 2 days before the planned rapid weight loss procedure a written menu in the Kcalmar.pro program together with a shopping list and method of preparation and planned supplementation. The menu will be sent via e-mail. The expected rapid weight loss process will occur over 5 days (days 10-14). There was a 2-hour break between the anthropometric measurements and the start of the second simulated powerlifting competition, during which the competitors from the experimental group used a regeneration strategy consisting in consuming a bolus of 800 ml of Oral Rehydration Solution and then consuming 150% of the fluid weight they lost in the process of rapid weight reduction until the start of the simulated competition. All competitors consumed approximately 100 g of carbohydrates between body weight measurement and the start. During the simulated powerlifting competition, all participants had access to fluids and food ad libitum.

The following strategies will be used to monitor adherence:
- For adherence to eating habits: 3-day food diary: the diet will be checked for provided kilocalories, protein, carbohydrates, fats, minerals, vitamins, and dietary fiber according to the Institute of Food and Nutrition and USDA National Nutrient Database.
- For adherence to training restrictions: email information sent by the athlete.
- For adherence to a rapid 5% body weight loss strategy: body composition analysis performed using the InBody570 analyzer as well as constant e-mail and phone contact with athletes.
Intervention code [1] 323183 0
Lifestyle
Intervention code [2] 323184 0
Treatment: Other
Comparator / control treatment
The control group maintains their standard eating habits for weight maintenance and thus does not result in a rapid weight loss of 5% body mass. The diet of participants in the control group will be unchanged and at the discretion of the participant.
Control group
Active

Outcomes
Primary outcome [1] 330834 0
The maximal strength capacity using TOTAL (squat + benchpress + deadlift) test in simulated powerlifting competitions.
Timepoint [1] 330834 0
7 and 14 (primary endpoint) days post-intervention commencement
Secondary outcome [1] 407784 0
Strength capacity in relation to body weight using IPF Good Lift in powerlifting competitions.
Timepoint [1] 407784 0
7 and 14 days post-intervention commencement
Secondary outcome [2] 407785 0
Strength capacity in relation to body weight using IPF Good Lift Bench Press in powerlifting competitions.
Timepoint [2] 407785 0
7 and 14 days post-intervention commencement
Secondary outcome [3] 407786 0
The body composition using the bioelectrical impedance analysis (BIA) method
Timepoint [3] 407786 0
7 days post-intervention commencement
Secondary outcome [4] 410785 0
Dietary habits using a 3-day food diary according to the USDA National Nutrient Database (this is a primary outcome)
Timepoint [4] 410785 0
3, 4 and 5 days post-intervention commencement
Secondary outcome [5] 410786 0
Rating Perceived Exertion (10-points scale)
Timepoint [5] 410786 0
7 and 14 days post-intervention commencement

Eligibility
Key inclusion criteria
1. Male sex.
2. Practicing powerlifting for at least 2 years.
3. Participation in at least one powerlifting competition.
4. Informed consent to participate in the study.
Minimum age
19 Years
Maximum age
40 Years
Sex
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
1. Use of doping substances and methods.
2. Medical contraindications indicated by a doctor.

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)
Central randomisation by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e., computerised 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
Efficacy
Statistical methods / analysis
Statistical analysis
Statistical analysis of the results will be performed in Statistica 13 (TIBCO Software Inc.). Comparison of qualitative variables in groups will be made using the Chi-square test (with Yates correction for 2x2 tables) or Fisher's exact test where low expected numbers appear in tables. Comparison of values of quantitative variables in two groups will be done using Student's t-test for variables with normal distribution or Mann-Whitney test where the distribution of the variable is non-normal. Comparison of the values of quantitative variables in three and more groups will be made using analysis of variance (ANOVA) for variables with normal distribution or Kruskal-Wallis test in the absence of normality of the variable distribution. Once statistically significant differences are detected, the post-hoc analysis will be performed using Tukey's HSD test or Dunn's test (respectively, when the normal distribution is confirmed or not) to identify statistically significantly different groups. Correlations between quantitative variables were analyzed using Pearson's correlation coefficient (for variables with normal distribution) or Spearman's correlation coefficient (when the distribution of variables is non-normal). The level of statistical significance will be set at p<0.05.

Sample size
Sample size analysis was performed in Statistica 13 (TIBCO Software Inc.) based on available results from Durguerian et al. It was evaluated how the maximum strength capacity of the athletes expressed as Total (kg) differed between two groups (Group 1 vs. Group 2). The estimated sample size was calculated based on the t-test for means of two samples (t-test for independent samples). Parameters: the mean difference in Group 1 was 8 kg (SD=4.5 kg); the mean in Group 2 was 2.8 (SD = 4.2); The alpha level was set at 0.05 and the power of the test was set at 0.8. It was also assumed that there was no correlation of the variables evaluated and the two-sided null hypothesis was accepted. Based on the parameters, an estimated sample size of 13 patients in each group was obtained. Additionally, the risk of losing patients in the study was assumed to be 15%. The final sample size is 15 participants in each group

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
4/07/2022
Actual
1/11/2022
Date of last participant enrolment
Anticipated
25/08/2022
Actual
27/03/2023
Date of last data collection
Anticipated
8/09/2022
Actual
23/04/2023
Sample size
Target
30
Accrual to date
Final
30
Recruitment outside Australia
Country [1] 24680 0
Poland
State/province [1] 24680 0
Lower Silesia

Funding & Sponsors
Funding source category [1] 311067 0
University
Name [1] 311067 0
Wroclaw University of Health and Sport Sciences, Poland
Country [1] 311067 0
Poland
Primary sponsor type
Individual
Name
Arkadiusz Matras
Address
Department of Biomechanics, Wroclaw University of Health and Sport Sciences, Mickiewicza 58 Street, 51-684 Wroclaw, Poland
Country
Poland
Secondary sponsor category [1] 312401 0
None
Name [1] 312401 0
Address [1] 312401 0
Country [1] 312401 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 310611 0
Senate Committee on Research Ethics of the Wroclaw University of Health and Sport Sciences, Wroclaw, Poland
Ethics committee address [1] 310611 0
Al. I.J. Paderewskiego 35, 51-612 Wroclaw, Poland
Ethics committee country [1] 310611 0
Poland
Date submitted for ethics approval [1] 310611 0
01/12/2021
Approval date [1] 310611 0
31/12/2021
Ethics approval number [1] 310611 0
18/2021

Summary
Brief summary
Aim:
Assessment of the effect of a rapid weight loss by approximately of 5% body mass on maximal strength capacity levels in powerlifters

Research questions:
1. Is the body composition of powerlifters related to their maximum strength capabilities?
2. Are powerlifters' eating habits related to their maximum strength capabilities?
3. Is the use of a strategy leading to a rapid reduction of approximately 5% of body weight associated with a change in the assessment of perceived exertion during simulated powerlifting competitions?
4. Is the use of a strategy leading to a rapid reduction of approximately 5% of body weight associated with a change in mood?
5. Is the athletes' lifestyle related to their maximum strength capabilities?

Research hypotheses:
1. The body composition of powerlifters is related to their maximum strength capabilities.
2. The eating habits of powerlifters are related to their maximum strength capabilities
3. The use of a strategy leading to a rapid weight loss approximately 5% is associated with a change in the assessment of perceived exertion during simulated powerlifting competitions.
4. Using a strategy leading to rapid weight loss by about 5% is associated with a change in mood.
5. The lifestyle of powerlifters is not related to their maximum strength capabilities

Research intervention:
1. Implementation of a ketogenic diet, low-fiber diet, and dehydration to induce a rapid loss of 5% of body mass.
2. Application of a recuperation process between weigh-ins and simulated competitions consisting of consuming a bolus of 800 ml of Oral Rehydration Solution and then consuming 150% of the fluid weight they lost in the process of rapid weight reduction until the start of the simulated competition. All competitors consumed approximately 100 g of carbohydrates between body weight measurement and the start. During the simulated powerlifting competition, all participants had access to fluids and food ad libitum"
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 118258 0
Mr Arkadiusz Matras, MSc, PhDc
Address 118258 0
Department of Biomechanics
Wroclaw University of Health and Sport Sciences
Mickiewicza 58 Street, 51-684 Wroclaw, Poland
Country 118258 0
Poland
Phone 118258 0
+48782155621
Fax 118258 0
Email 118258 0
[email protected]
Contact person for public queries
Name 118259 0
Arkadiusz Matras, MSc, PhDc
Address 118259 0
Department of Biomechanics
Wroclaw University of Health and Sport Sciences
Mickiewicza 58 Street, 51-684 Wroclaw, Poland
Country 118259 0
Poland
Phone 118259 0
+48782155621
Fax 118259 0
Email 118259 0
[email protected]
Contact person for scientific queries
Name 118260 0
Arkadiusz Matras, MSc, PhDc
Address 118260 0
Department of Biomechanics
Wroclaw University of Health and Sport Sciences
Mickiewicza 58 Street, 51-684 Wroclaw, Poland
Country 118260 0
Poland
Phone 118260 0
+48782155621
Fax 118260 0
Email 118260 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Individual participant data underlying published results only
When will data be available (start and end dates)?
Immediately the following publication on reasonable request (available for 5 years after publication)
Available to whom?
Only to researchers who provide a methodologically relevant explanation
Available for what types of analyses?
Only to achieve the purposes of the approved request
How or where can data be obtained?
The data can be obtained by emailing the principal investigator ([email protected])


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

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