Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12621001709831
Ethics application status
Approved
Date submitted
29/11/2021
Date registered
13/12/2021
Date last updated
31/10/2022
Date data sharing statement initially provided
13/12/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
Effect of pre-sleep alpha-lactalbumin supplementation on the sleep and performance of athletes with sleep difficulties within habitual environments
Scientific title
Effect of pre-sleep alpha-lactalbumin supplementation on the sleep and performance of athletes with sleep difficulties within habitual environments
Secondary ID [1] 305912 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Sleep difficulty 324491 0
Condition category
Condition code
Mental Health 321974 321974 0 0
Other mental health disorders
Neurological 322116 322116 0 0
Other neurological disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Study design - Randomised, double-blinded, counterbalanced, crossover design
(Crossover experimental group = 40 g alpha-lactalbumin; Crossover placebo group = 40 g collagen)

As a cross-over trial, to limit any potential carry over effects of the alpha-lactalbumin into the next intervention period, a minimum six-night washout period is to be observed. Further, to ensure the influence of female hormones is low throughout the intervention periods (as this can confound sleep outcomes), naturally menstruating females are to complete both intervention periods during the early follicular phase. This phase will be determined through menses and menstrual cycle mapping.

Experimental group - alpha-lactalbumin
Product - BiPRO Alpha 9000 (Agropur Inc, Appleton, WI)
Dose - 40 grams once daily
Duration - 7 days
Dosage form - Powder, oral
Route of Administration - Oral
Active ingredient - Tryptophan (1.9 g)

To investigate the effect of evening supplementation (2 hours prior to sleep) of 40 g alpha-lactalbumin for seven nights on the sleep, mood, recovery, and sports-related performance of athletes with sleep difficulties compared to placebo.

Sports-related performance measures will be completed on multiple occasions. Performance measures will be tested the day immediately following seven days of supplementation (alpha-lactalbumin and placebo), and the day following the six-day washout period to observe any “legacy” effect of alpha-lactalbumin supplementation on performance. These sports-related performance tests will be completed at the Deakin University Burwood campus.

To control for protein's potential confounding influence on the effectiveness of alpha-lactalbumin supplementation, participants diet will be standardised to meet habitual energy intake, and 1.2 g/kg of body weight of daily protein. This amount is at the lowest end of recommended protein amounts for athletes.

Participants will complete the intervention periods within their habitual environments. Supplements and meals will be provided to participants in advance by a member of the research team. Adherence to supplement and meal consumption will be monitored through reporting in a dietary software app. Further, all meals (3 main meals + 2 snacks) will be provided by a member of the research team, with participants able to consume additional low-protein snacks if they wish to do so (must be replicated by the participant for both intervention periods). The dietary supplement (alpha-lactalbumin or placebo) will be prepared and matched for taste by an external researcher to ensure both participants and the research team remain blind to the treatments.
Intervention code [1] 322310 0
Treatment: Other
Comparator / control treatment
Placebo group - collagen
Product - Collagen Regenerate (Body Science, Burleigh, QLD)
Dose - 40 grams once daily
Duration - 7 days
Dosage form - Powder, oral
Route of Administration - Oral

As this placebo supplement will be consumed by participants in their habitual environments, adherence will be monitored through reporting in a dietary software app.

Both the placebo and experimental group will receive the same standardised meals throughout the intervention period
Control group
Placebo

Outcomes
Primary outcome [1] 329722 0
Total sleep time (hrs) measured through actigraphy (Actical Z).
Timepoint [1] 329722 0
Each night across both 7-day supplementation periods.
All timepoints across both intervention periods are considered primary timepoints
Primary outcome [2] 329723 0
Sleep onset latency (hrs) measured through actigraphy (Actical Z).
Timepoint [2] 329723 0
Each night across both 7-day supplementation periods.
All timepoints across both intervention periods are considered primary timepoints
Primary outcome [3] 329724 0
Sleep efficiency (%) measured through actigraphy (Actical Z).
Timepoint [3] 329724 0
Each night across both 7-day supplementation periods.
All timepoints across both intervention periods are considered primary timepoints
Secondary outcome [1] 403588 0
PRIMARY OUTCOME
Wake after sleep onset (min) measured through actigraphy (Actical Z).
Timepoint [1] 403588 0
PRIMARY TIMEPOINT
Each night across both 7-day supplementation periods.
All timepoints across both intervention periods are considered primary timepoints
Secondary outcome [2] 403590 0
Changes in subjective mood scores as assessed via the Brunel Mood Scale
Timepoint [2] 403590 0
All measured timepoints in the evening and morning are considered as secondary timepoints.
Secondary outcome [3] 403591 0
Changes in subjective recovery scores as assessed via the Short Recovery and Stress Scale
Timepoint [3] 403591 0
All measured timepoints in the evening and morning are considered as secondary timepoints.
Secondary outcome [4] 403592 0
Changes in subjective sleepiness scores as assessed via the Karolinska Sleepiness Scale
Timepoint [4] 403592 0
All measured timepoints in the evening and morning are considered as secondary timepoints.
Secondary outcome [5] 404160 0
PRIMARY OUTCOME

Yo-Yo Intermittent Recovery Test Level 1 distance
Timepoint [5] 404160 0
PRIMARY TIMEPOINT
The day immediately following each supplementation period (i.e., day 8 of both intervention period). This will be compared to two baseline measures completed prior to the first intervention period.

SECONDARY TIMEPOINT
The day immediately following both six-day washout periods following each intervention period
Secondary outcome [6] 404161 0
PRIMARY OUTCOME

Fatigue index across 30-second continuous jump test
Timepoint [6] 404161 0
PRIMARY TIMEPOINT
The day immediately following each supplementation period (i.e., day 8 of both intervention period). This will be compared to two baseline measures completed prior to the first intervention period.

SECONDARY TIMEPOINT
The day immediately following both six-day washout periods following each intervention period
Secondary outcome [7] 404162 0
PRIMARY OUTCOME

Reaction time via Dynavision light board
Timepoint [7] 404162 0
PRIMARY TIMEPOINT
The day immediately following each supplementation period (i.e., day 8 of both intervention period). This will be compared to two baseline measures completed prior to the first intervention period.

SECONDARY TIMEPOINT
The day immediately following both six-day washout periods following each intervention period

Eligibility
Key inclusion criteria
Participants must be between 18-40 years old, and actively competing in a team-sport and registered with a club at a minimum community level. Participants will be recruited from a range of invasion team-sports (e.g., football, rugby, soccer) with participants to be completing structured exercise at least three times per week for a minimum total of five hours per week to meet “trained athlete” guidelines. Further, participants will be screened using the Athlete Sleep Screening Questionnaire and Pittsburgh Sleep Quality Index, and those with a sleep difficulty score equal to or greater than 5, global PSQI score >5 and a sleep onset latency >15 minutes will be eligible. These scores coincide with equal to or greater than mild sleep difficulty and poor-quality sleep, which are the targeted participants for this study.
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion: smoking, excessive alcohol consumption (>17 standard drinks per week), dairy allergy, high caffeine use (e.g., >5 mg·kg-1·d-1), antidepressant or sleep medication use, current or recently finished night shift work, recent transmeridian travel, fluctuating bedtimes, and pregnancy. These exclusions criteria relate to confounding influences that may affect sleep or the plasma TRP:LNAA ratio.

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)
External researcher outside of research team to generate the sequence by which a participant will complete the crossover conditions. This will ensure both the research team and participant remain blinded to the treatment (i.e., placebo or alpha-lactalbumin) the participant is receiving.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
This will be done in a counterbalanced manner through simple randomisation techniques (i.e., coin toss).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Double-blinded
Randomised
Counterbalanced
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Statistical power calculations - Based on the primary outcome of sleep onset latency within previous literature. A two-sided t-test achieves 82% power to infer that the mean difference is not 0.00 when the total sample size of a 2x2 cross-over design is 24, the actual mean difference is 13.0, the standard deviation of the paired differences is 18.56, and the significance level is 0.05.

Statistical analysis - Initially, data cleaning will be performed to identify missing and corrupt data. Data will be analysed using generalised linear mixed models within StataIC 16 (StataCorp LLC, TX, USA). The effect of dietary intervention (i.e., placebo or alpha-lactalbumin) and period (i.e., sequence receiving condition) and their interaction, will be fitted as fixed effects to determine whether there was a difference in the effect of dietary intervention over period on dependant sleep variables (e.g., sleep efficiency), mood, and sports-related performance. As training load will be a potential confounder to the nutrition-sleep relationship, this will be included as a covariate within the linear mixed model. Participant identification number will be used as a random factor to account for repeated measures in each model.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
17/01/2022
Actual
17/06/2022
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
24
Accrual to date
5
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 310262 0
University
Name [1] 310262 0
Deakin University - Centre for Sport Research
Country [1] 310262 0
Australia
Primary sponsor type
University
Name
Deakin University
Address
221 Burwood Hwy, Burwood VIC 3125
Country
Australia
Secondary sponsor category [1] 311362 0
None
Name [1] 311362 0
Address [1] 311362 0
Country [1] 311362 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 309934 0
Deakin University Human Research Ethics Committee
Ethics committee address [1] 309934 0
221 Burwood Hwy, Burwood VIC 3125
Ethics committee country [1] 309934 0
Australia
Date submitted for ethics approval [1] 309934 0
17/11/2021
Approval date [1] 309934 0
24/03/2022
Ethics approval number [1] 309934 0
2021-416

Summary
Brief summary
Sleep is important for the optimal health and performance of an athlete. Data suggests that as sleep debt accumulates, sports-related performance is further reduced. Athletes with sleep difficulties are prone to accumulating sleep debt and are therefore of greater risk of impaired performance. This athlete cohort need sleep intervention, with recent research indicating diet influences an athlete’s sleep. Protein supplements high in the amino acid tryptophan may promote sleep through increases in melatonin, with individuals experiencing sleep difficulties believed to be more receptive to the sleep-promoting benefits of tryptophan. Therefore, this study aims to investigate the effect of a potentially sleep-promoting protein supplement (alpha-lactalbumin) on the sleep and performance of athletes with sleep difficulties.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 115894 0
Dr Dominique Condo
Address 115894 0
221 Burwood Hwy, Burwood VIC 3125
Deakin University
Country 115894 0
Australia
Phone 115894 0
+61 3 9244 5487
Fax 115894 0
Email 115894 0
dominique.condo@deakin.edu.au
Contact person for public queries
Name 115895 0
Dr Dominique Condo
Address 115895 0
221 Burwood Hwy, Burwood VIC 3125
Deakin University
Country 115895 0
Australia
Phone 115895 0
+61 3 9244 5487
Fax 115895 0
Email 115895 0
dominique.condo@deakin.edu.au
Contact person for scientific queries
Name 115896 0
Dr Dominique Condo
Address 115896 0
221 Burwood Hwy, Burwood VIC 3125
Deakin University
Country 115896 0
Australia
Phone 115896 0
+61 3 9244 5487
Fax 115896 0
Email 115896 0
dominique.condo@deakin.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?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
14249Study protocol    383209-(Uploaded-29-11-2021-12-12-12)-Study-related document.docx
14250Informed consent form    383209-(Uploaded-29-11-2021-12-09-38)-Study-related document.docx
14251Ethical approval    383209-(Uploaded-26-10-2022-21-48-23)-Study-related document.pdf



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.