Vitamin D status as a predictor of outcomes of experimentally-induced muscle pain and weakness in young, healthy volunteers

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Vitamin D receptor's presence in skeletal muscle indicates a role in muscle function and clinical symptoms of vitamin D deficiency include muscle weakness and pain. No one has yet examined the association of vitamin D status and experimentally-induced muscle pain or weakness in young, healthy people. Methods: Muscle damage to the elbow flexors was induced with eccentric exercise (EE) in 27 men (mean age 22.5 yr) and 21 women (mean age 22.6 yr). Muscle pain ratings from unloaded movement and isometric contractions and peak isometric force were collected before EE and for 4 days post-EE. Serum 25-hydroxy vitamin D (25OHD) was assayed 2 days post-EE. Linear regression was used to determine if 25OHD was a predictor of any outcome. Results: Serum 25OHD did not predict any of the pain or strength measures. In men: R2 for pain ratings ranged from 0 to 0.02, and p-values from 0.48 to 1.00. R2 for IF ranged from 0 to 0.02 and p-values from 0.48 to 1.00. In women: R2 for pain ratings ranged from 0.01 to 0.21, and p-values from 0.14 to 0.74. R2 for IF ranged from 0 to 0.04 and p-values from 0.41 to 0.90. Conclusions: Serum 25OHD did not predict muscle pain or strength after EE-induced muscle damage in young healthy men and women.