The ANZCTR website will be unavailable from 1pm until 3pm (AEDT) on Wednesday the 30th of October for website maintenance. Please be sure to log out of the system in order to avoid any loss of data.

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
ACTRN12612001233819
Ethics application status
Approved
Date submitted
2/11/2012
Date registered
22/11/2012
Date last updated
22/11/2012
Type of registration
Retrospectively registered

Titles & IDs
Public title
Vitamin D Status and Effect of Supplementation on Strength, Speed and Body Composition in rugby union players.
Scientific title
A double-blind, randomised, placebo controlled study of 12 weeks of oral vitamin D supplementation on strength, speed and body composition in elite rugby union players residing in Southern New Zealand.
Secondary ID [1] 281491 0
Nil.
Universal Trial Number (UTN)
U1111-1136-6736
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Strength, in elite rugby union players 287759 0
Sprinting speed, in elite rugby union players 287760 0
Body composition, in elite rugby union players 287761 0
elite sport performance 287762 0
Condition category
Condition code
Musculoskeletal 288102 288102 0 0
Normal musculoskeletal and cartilage development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Oral Vitamin D supplementation (50,000 IU cholecalciferol) or placebo taken once a fortnight over 11-12 weeks of pre-season training for the New Zealand ITM Cup domestic rugby union competition. The duration of treatment is designed to coincide with local performance testing (done at 5 and 11 weeks in one squad, and after 6 and 12 weeks in the other squad). The supplementation is taken as a single oral tablet (Cal-D-Forte, PSM Healthcare Ltd, Auckland NZ) once a fortnight.
Intervention code [1] 286003 0
Early detection / Screening
Intervention code [2] 286004 0
Treatment: Other
Comparator / control treatment
Placebo: a tablet with similar appearance to the active treatment, containing microcrystalline cellulose, dicalcium phosphate, magnesium stearate and Talc T63B.
Control group
Placebo

Outcomes
Primary outcome [1] 288306 0
Sprint speed. Power calculations were performed for 30 metre sprint time (seconds), measured by timing lights as part of routine performance testing.
Timepoint [1] 288306 0
At Baseline, either 5 or 6 weeks and either 11 or 12 weeks (squad dependent) following baseline data collection.
Primary outcome [2] 288307 0
10 metre sprint time (seconds), measured by timing lights as part of routine performance testing.
Timepoint [2] 288307 0
At Baseline, either 5 or 6 weeks and either 11 or 12 weeks (squad dependent) following baseline data collection.
Secondary outcome [1] 299806 0
Strength. Measured by Bench Press, Bench Pull, Weighted Reverse Grip Chin-Up and Squat or Box Squat 1 Repetition Maximum (kg), obtained as part of routine performance testing.
Timepoint [1] 299806 0
At Baseline, either 5 or 6 weeks and either 11 or 12 weeks (squad dependent) following baseline data collection.
Secondary outcome [2] 299807 0
Body composition, specifically body fat (%) and lean mass (kg) measured by Dual X-ray Absorptiometry.
Timepoint [2] 299807 0
At Baseline and either 11 or 12 weeks (squad dependent) following baseline data collection
Secondary outcome [3] 299808 0
Vitamin D status, measured by serum 25-hydroxyvitaminD concentrations.
Timepoint [3] 299808 0
At Baseline, either 5 or 6 weeks and either 11 or 12 weeks (squad dependent) following baseline data collection.
Secondary outcome [4] 299809 0
Mood score, measured by Brunel Mood Scale questionnaire
Timepoint [4] 299809 0
At Baseline, either 5 or 6 weeks and either 11 or 12 weeks (squad dependent) following baseline data collection.
Secondary outcome [5] 299810 0
Reaction Time, measured by a computerised reaction time test (click when you see the green dot) developed by colleagues in the Dept of Psychology, University of Otago.
Timepoint [5] 299810 0
At Baseline, either 5 or 6 weeks and either 11 or 12 weeks (squad dependent) following baseline data collection.

Eligibility
Key inclusion criteria
Rugby players training in the Otago and Southland ITM Cup pre-season training squads, including development players.
Aged 18 years and over, and able to undergo strength and speed testing.
Minimum age
18 Years
Maximum age
40 Years
Sex
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
Aged under 18 years of age; currently taking Vitamin D supplements; the presence of any chronic disease such as heart disease, diabetes or cancer; the presence of any conditions that affect hormone metabolism (primarily growth hormone and insulin metabolism); smokers.

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)
Participants were enrolled after hearing about the research study at a presentation, or via their Strength and Conditioning Coach. Randomisation was stratified by location (Otago or Southland) and by training regime (by strength training, power training or hypertrophy training for example). A third party (not involved with the research group or with the squads) placed the allocated treatments into white containers with each participants initials on them, which were provided to the squads strength and conditioning coaches.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation was stratified by location (Otago or Southland) and by training regime (by strength training, power training or hypertrophy training for example). The stratification information for each squad was sent to a statistician off-site, who used computerised sequence generation to allocate treatment 1 or 2 (placebo or vitamin D) to each participant enrolled. A third party then placed the allocated treatments into white containers with each participants initials on them, which were provided to the squads strength and conditioning coaches. The strength and conditioning coaches then facilitated access to the participants bottles once a fortnight, to ensure compliance. All of this was done independently to the researchers, to ensure double-blind status was maintained.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
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 outside Australia
Country [1] 4665 0
New Zealand
State/province [1] 4665 0
Otago
Country [2] 4666 0
New Zealand
State/province [2] 4666 0
Southland

Funding & Sponsors
Funding source category [1] 286267 0
University
Name [1] 286267 0
Department of Human Nutrition Performance Based Research Fund
Country [1] 286267 0
New Zealand
Primary sponsor type
Individual
Name
Dr Kirsty Fairbairn
Address
Department of Human Nutrition
PO Box 56
Dunedin 9054
Country
New Zealand
Secondary sponsor category [1] 285067 0
Individual
Name [1] 285067 0
Dr Tracy Perry
Address [1] 285067 0
Department of Human Nutrition
PO Box 56
Dunedin 9054
Country [1] 285067 0
New Zealand
Other collaborator category [1] 277156 0
Individual
Name [1] 277156 0
Professor Murray Skeaff
Address [1] 277156 0
Department of Human Nutrition
PO Box 56
Dunedin 9054
Country [1] 277156 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 288342 0
Human Ethics Committee, The University of Otago
Ethics committee address [1] 288342 0
Ethics committee country [1] 288342 0
New Zealand
Date submitted for ethics approval [1] 288342 0
Approval date [1] 288342 0
21/03/2011
Ethics approval number [1] 288342 0
1/11/0064

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 34914 0
Address 34914 0
Country 34914 0
Phone 34914 0
Fax 34914 0
Email 34914 0
Contact person for public queries
Name 18161 0
Dr Kirsty Fairbairn
Address 18161 0
Department of Human Nutrition
The University of Otago
PO Box 56
Dunedin 9054
Country 18161 0
New Zealand
Phone 18161 0
+64 3 479 5359
Fax 18161 0
+64 3 479 7958
Email 18161 0
Contact person for scientific queries
Name 9089 0
Dr Kirsty Fairbairn
Address 9089 0
Department of Human Nutrition
The University of Otago
PO Box 56
Dunedin 9054
Country 9089 0
New Zealand
Phone 9089 0
+64 3 479 5359
Fax 9089 0
+64 3 479 7958
Email 9089 0

No information has been provided regarding IPD availability


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.