Research

Hormonal

In professional athletes with vitamin D insufficiency during winter months, supplementation with 5000 IU/day of vitamin D3 for 8 weeks significantly improves vertical jump height and 10-meter sprint times.

If you are a competitive athlete training in a northern climate during winter, get your Vitamin D levels checked. If you are deficient, taking 5000 IU of Vitamin D3 daily for 8 weeks can significantly improve your sprint speed and jumping power. This is not just about bone health; it directly impacts performance metrics like vertical jump and 10m sprint times.

ModerateSupportsMEDIUM confidence
There was a significant increase in 10 m sprint times (P = 0.008) and vertical-jump (P = 0.008) in the vitamin D group whereas the placebo showed no change (P = 0.587 and P = 0.204 respectively).
Graeme L. Close et al. · Journal of Sports Sciences · 2012

Why this rating

Randomized controlled trial with placebo control, but small sample size (n=10 for performance) and single-team cohort limits generalizability.

Source

Assessment of vitamin D concentration in non-supplemented professional athletes and healthy adults during the winter months in the UK: implications for skeletal muscle function

Graeme L. Close et al. · Journal of Sports Sciences · 2012

DOI 10.1080/02640414.2012.733822

rct · n=91Cited 242×
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DOI resolved against Crossref · corpus check 2026-06-10

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