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NCT01518725 · ClinicalTrials.gov registry record · Phase 4

The Effect of Vitamin D Supplementation on Muscle Power in Elite Cyclist

A Phase 4 study of Muscle Power, sponsored by Oklahoma State University.

Completed
Registry status
Phase 4
Development phase
103
Enrollment target
1
Study location

NCT01518725: Completed Phase 4 study of Muscle Power, sponsored by Oklahoma State University.

NCT01518725 is a Phase 4 study of Muscle Power that has completed, run by Oklahoma State University. The registered enrollment target is 103 participants, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (80% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT01518725, a Phase 4 study of Muscle Power, has completed, sponsored by Oklahoma State University.

COMPLETED
Registry status
Phase 4
Development phase
103 participants
Enrollment target
1
Study location

Study Summary

The purpose of this study is to evaluate the change in vitamin D status with the change in muscular strength and muscular power in highly trained athletes over a 9-month study period. The investigators hypothesize that the greatest muscular strength and power gains will be demonstrated in the athletes who achieve and maintain a 25(OH)-D \> 50 ng/mL (but \< 100 ng/mL) over the 6 month study duration. This hypothesis will be tested by carrying out the following specific aims: Aim 1. to determine the extent to which increasing serum 25(OH)D to \> 50 ng/mL is associated with improved muscular power by assessing specific performance measures (e.g. Vertical Jump Test and Wingate test) relative to lean body mass; and Aim 2. to examine the correlation between vitamin D status and muscular power over time.

Primary Outcome

Non fasting blood samples will be used for the evaluation of vitamin D metabolites. Venous blood (\~5 cc) will be collected from the non-dominant arm by a trained phlebotomist, centrifuged at 2,000 rpm and serum stored at -80° C. Two vitamin D metabolites, 25 (OH) D and 1,25 (OH)2 D and serum PTH will be assessed.

Conditions Studied

Interventions

  • DIETARY_SUPPLEMENT Placebo
  • DIETARY_SUPPLEMENT Vitamin D

Study Locations (1)

Oklahoma

  • Oklahoma State University - Stillwater

Trial Details

FieldValue
Enrollment Target 103 participants
Start Date 2012-01
Est. Completion 2013-08
Phase Phase 4
Oklahoma State University

26 total trials

What the finished NCT01518725 record still lists

NCT01518725 is an interventional study that assigns participants to a tested intervention. The registered 103 participants enrollment target is mid-sized for trials with a published cap, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (80% lower).

The record links to 1 condition, with Muscle Power appearing as the primary indexed condition, and to 2 interventions - of which Placebo is the first listed.

NCT01518725 reports a single indexed study location in Oklahoma.

Frequently Asked Questions

What is clinical trial NCT01518725 about?

NCT01518725 is a clinical study titled "The Effect of Vitamin D Supplementation on Muscle Power in Elite Cyclist". The purpose of this study is to evaluate the change in vitamin D status with the change in muscular strength and muscular power in highly trained athletes over a 9-month study period. The investigators hypothesize that the greatest muscular strength and power gains will be demonstrated in the athlet...

What is the current status of trial NCT01518725?

This trial is currently completed. It is a Phase 4 study. The enrollment target is 103 participants. The study started on 2012-01. Estimated completion is 2013-08.

What conditions does trial NCT01518725 study?

This clinical trial studies the following conditions: Muscle Power.

What interventions are being tested in trial NCT01518725?

The interventions under investigation include: Placebo (DIETARY_SUPPLEMENT), Vitamin D (DIETARY_SUPPLEMENT).

Who is sponsoring clinical trial NCT01518725?

This trial is sponsored by Oklahoma State University, which has 26 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT01518725 being conducted?

This trial has 1 study location across Oklahoma. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

How this trial's enrollment target compares

Where NCT01518725's enrollment target sits among peer trials

103 760th of 2000 higher than 1,237 of 2,000 other Phase 4 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 4 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT01518725, the US trial registry maintained by the National Library of Medicine. NCT01518725 (mid enrollment · single site footprint · completed) retrieved and formatted by PlainTrial, see methodology.