So, is it the effects on calcium and nerve function (neurotransmitter release), the effects on calcium and muscular contraction, the antioxidants properties, some other function? Supplementing Vitamin D and getting people more sun exposure are easy things to do...
"These findings reveal an important new relationship between parathyroid hormone and gait stability parameters and add to understanding of the role of 25-OHD in motor control of gait and dynamic balance in community-dwelling women across a wide age span."
Bird ML, El Haber N, Batchelor F, Hill K, Wark JD. Vitamin D and parathyroid hormone are associated with gait instability and poor balance performance in mid-age to older aged women. Gait Posture. 2017 Sep 28;59:71-75. doi: 10.1016/j.gaitpost.2017.09.036. [Epub ahead of print]