Background
Vitamin D plays an important and increasingly understood role in muscle health and performance. Vitamin D exhibits a nuclear receptor for transcription interaction and a transmembrane receptor, giving it genomic and non-genomic interactions. Vitamin D receptors have been described that affect muscle function. Vitamin D has also been correlated with muscle performance. Beyond its role in normal muscle function, vitamin D deficiency can interact with statins to produce myalgia–myositis, which can be reversed by normalizing serum vitamin D [7,13]. Exertional rhabdomyolysis may occur in diverse settings including marathons, ice skating, bicycling and swimming. Our hypothesis is that subjects with pre-existing low serum 25OHD are selected out for exertional rhabdomyolysis during strenuous activities.

Methods
We review exercise induced severe rhabdomyolysis in association with heat stroke with subsequent disseminated intravascular coagulation in a thin, athletic, dark skinned, conditioned young man, occurring in the setting of a 5K race, subsequently found to have severe 25 OH vitamin D deficiency (6ng/ml, laboratory lower normal limit >30ng/ml).

Conclusion
We suggest that when very low vitamin D is documented, it be normalized before major prolonged exertion. We hypothesize that normalization of vitamin D before heavy exertion could perhaps prevent the severe muscle damage events and sequelae as was the case for this patient.

Source: Elsevier