High-Dose Vitamin D3 in Athletes

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

Athletes with vitamin D deficiency or insufficiency receive either vitamin D3 or a placebo for 4 or 8 weeks. Before and after the supplementation, researchers measure blood nutrients, body composition, muscle function with tensiomyography, and cognitive performance using standardized tests. The trial uses randomization and a parallel-group design to assess potential physiological and cognitive changes from high-dose vitamin D3. The study is conducted at the Functional Research Laboratory at AWF Katowice. Participants are adults with substantial training history and no recent injuries.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* a minimum of 8 years of training experience,
* absence of injuries in the 6 months leading up to the assessments,
* consistent engagement in training sessions a minimum of 5 times per week over the last 6 months.

Exclusion Criteria:

* vitamin D supplementation within one month prior to the study,
* use of multivitamin supplements,
* intestinal disorders.

Where it's running

• The Jerzy Kukuczka Academy of Physical Education in Katowice
  Katowice, Mikołowska 72a, Poland Recruiting

Study contacts

• Study coordinator: Małgorzata Michalczyk, Profesor
• Email: m.michalczyk@awf.katowice.pl
• Phone: +48535016532

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.