What do studies say about Vitamin D Training?

Studies indicate that vitamin D plays a key role in muscle function, strength, and recovery. Adequate vitamin D levels may enhance training performance, especially in strength and endurance sports. However, evidence for a direct causal effect of vitamin D supplementation on training outcomes is mixed. Some studies show benefits in individuals with low baseline levels, while others find no significant effect in those already sufficient. The term 'Vitamin D Training' is not clearly defined—it may refer to training to increase vitamin D levels (e.g., sun exposure) or combining supplementation with exercise. The evidence base is moderate but not conclusive. Caveat: vitamin D is fat-soluble; overdose possible; individual baseline and lifestyle factors matter.