February 23, 2009 --Low levels of vitamin Dmay drain teenage girls of some of their muscle power. A study conducted in the United Kingdom at the University of Manchester looked at 99 girls ages 12-to-14. It found that those with lower vitamin D levels in their blood performed worse in jumping and leg muscle power tests.
Researchers say it appears a lack of vitamin D hinders the ability of muscles to contract. That raises concerns because muscle force on the bones helps build bone mass and strength.