In conclusion , we observed no improvement in muscle strength after the administration of vitamin D with or without calcium supplements .
We did find a small but significant deterioration of mobility .
BACKGROUND It has been suggested that vitamin D status or supplementation is important for maintaining or improving muscle strength and mobility in older adults .
The study results , however , do not provide consistent results .
We therefore aim ed to summarise the available evidence systematic ally , including only studies conducted in community-dwelling older persons .
Effects of vitamin D supplementation on neuroplasticity in older adults: a double-blinded, placebo-controlled randomised trial
Summary Vitamin D can improve muscle function and reduce  falls  , but whether it can strengthen neural connections within the brain and nervous system is not known . This 10-week r and omised controlled trial indicates that treatment with 2,000 IU/day vitamin D3 does not significantly alter neuroplasticity relative to placebo in older adults . Introduction The purpose of this study was to examine the effects of vitamin D supplementation on neuroplasticity , serum brain-derived neurotrophic factor ( BDNF ) and muscle strength and function in older adults . Methods This was a 10-week double-blinded , placebo-controlled r and omised trial in which 26 older adults with 25-hydroxyvitamin D [ 25OHD ] concentrations 25–60 nmol/L were r and omised to 2,000 IU/day vitamin D3 or matched placebo .  Single- and paired-pulse transcranial magnetic stimulation applied over the motor cortex was used to assess changes in motor-evoked potentials ( MEPs ) and short-interval intracortical inhibition ( SICI ) , as measures of corticospinal excitability and inhibition respectively , by recording electromyography ( EMG ) responses to stimulation from the wrist extensors . Changes in muscle strength , stair climbing power , gait ( timed-up- and -go ) , dynamic balance ( four square step test ) , serum 25(OH)D and BDNF concentrations were also measured . Results After 10 weeks , mean 25(OH)D levels increased from 46 to 81 nmol/L in the vitamin D group with no change in the placebo group . The vitamin D group experienced a significant 8–11 % increase in muscle strength and a reduction in cortical excitability ( MEP amplitude ) and SICI relative to baseline ( all P < 0.05 ) , but these changes were not significantly different from placebo . There was no effect of  vitamin D  on muscle power , function or BDNF . Conclusions Daily supplementation with 2,000 IU vitamin D3 for 10 weeks had no significant effect on neuroplasticity compared to placebo , but the finding that vitamin D treatment alone was associated with a decrease in corticospinal excitability and intracortical inhibition warrants further investigation as this suggests that it may improve the efficacy of neural transmission within the corticospinal pathway
In conclusion , we observed no improvement in muscle strength after the administration of vitamin D with or without calcium supplements .
We did find a small but significant deterioration of mobility .
BACKGROUND It has been suggested that vitamin D status or supplementation is important for maintaining or improving muscle strength and mobility in older adults .
The study results , however , do not provide consistent results .
We therefore aim ed to summarise the available evidence systematic ally , including only studies conducted in community-dwelling older persons .