Effects of vitamin D supplementation in physically active adults

Not Applicable

Completed

• Conditions: Muscle strength and body composition conditioning; Increasing resting metabolic rate (RMR); Metabolic and Endocrine - Normal metabolism and endocrine development and function; Musculoskeletal - Normal musculoskeletal and cartilage development and function

• Registration Number: ACTRN12620000896976
• Lead Sponsor: Curtin University

Brief Summary

Thirty-one adults completed the study (19 females and 12 males; mean ± SD; age = 26.6 ± 4.9 y; height = 170.0 ± 8.4 cm; body-mass = 71.7 ± 11.8 kg). The VitD group increased serum total 25(OH)D by 30 nmol·L-1 while the placebo group decreased total serum concentration by 21 nmol·L-1, reaching 123 (51) and 53 (42.2) nmol·L-1, med (IRQ) respectively. There were no significant changes in muscle strength or power, resting metabolic rate, and body composition over the 12-week period. Physically active participants already VitD sufficient have shown no additional effect of reaching higher serum total 25(OH)D concentrations after VitD3 supplementation.

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Completion: 2019-09-04
• Study Start: 2020-09-11
• Last Update Posted: 21 September 2020

Recruitment & Eligibility

• Status: Completed
• Sex: All
• Target Recruitment: 31

Inclusion Criteria

adults, 18-35 years old
-exercising at least three times per week with at least two of those sessions involving resistance training;
- no history of VitD3 supplementation in the last month;
- no current injuries that would prevent them from completing strength testing;
- no current use of multivitamins, medication, or other supplements that are related with VitD metabolism and body composition [including calcium, thyroxine, creatine and thermogenic supplements]).
- available to complete the tests at Curtin University and PathWest lab

Exclusion Criteria

none

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Muscular strength <br><br>Participants completed the test of 1-repetition maximum (1RM) for the bench press exercises following the procedures set out by Baechle and Earle to assess upper body strength. Briefly, participants had to lift progressively greater weights until a mass is identified that can only be lifted for one repetition for that exercise. [Pre supplementation period (week 0) and after the completion of 12 weeks supplementation period (week 12-13),];Leg Power<br><br>Participants completed a counter-movement vertical jump test, (Vertec Yardstick Jumping Device, Swift Performance, Australia) to assess leg power. [Pre supplementation period (week 0) and after the completion of 12 weeks supplementation period (week 12-13),]