30 Seconds Summary
Research Spotlight: Effects of Vitamin D3 supplementation on strength and body composition

  • Vitamin D3 supplementation in fall improves strength and body composition in collegiate swimmers.
  • Participants took 5000 IU of vitamin D3 daily for 12 weeks; control group received a placebo.
  • Vitamin D levels rose by 8% in supplemented group, but dropped by 44% in placebo group.
  • Improvements observed in squat, deadlift, and vertical jump for the Vitamin D3 group, but not in other strength exercises.
  • Body fat percentage decreased more significantly in the Vitamin D3 group compared to placebo.
  • Fat-free mass increased substantially in the Vitamin D3 group, with no significant change in the placebo group.
  • No major hormonal changes occurred in the Vitamin D3 group, while the placebo group experienced a decrease in free testosterone.
  • Supplementation effects suggest potential benefits for athletic performance, though dosing above recommended limits should be supervised by a medical professional.
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