Acute Effects of Vitamin D3 Supplementation on Muscle Strength in Judoka Athletes: A Randomized Placebo-Controlled, Double-Blind Trial Effects of Vitamin D3 Supplementation on Muscle Strength, Mass, and Physical Performance in Women with Vitamin D Insufficiency: A Randomized Placebo-Controlled Trial The impact of vitamin D3 supplementation on muscle function among HIV-infected children and young adults: a randomized controlled trial Influence of vitamin D mushroom powder supplementation on exercise-induced muscle damage in vitamin D insufficient high school athletes Vitamin D3 supplementation using an oral spray solution resolves deficiency but has no effect on VO2 max in Gaelic footballers: results from a randomised, double-blind, placebo-controlled trial Treatment of Vitamin D Deficiency Increases Lower Limb Muscle Strength in Institutionalized Older People Independently of Regular Physical Activity: A Randomized Double-Blind Controlled Trial A randomized study on the effect of vitamin D₃ supplementation on skeletal muscle morphology and vitamin D receptor concentration in older women. Skeletal muscle strength in young Asian Indian females after vitamin D and calcium supplementation: a double-blind randomized controlled clinical trial. Effects of Enhanced Exercise and Combined Vitamin D and Calcium Supplementation on Muscle Strength and Fracture Risk in Postmenopausal Chinese Women. The effects of vitamin D3 supplementation on serum total 25[OH]D concentration and physical performance: a randomised dose–response study Vitamin D3 Supplementation Does Not Improve Sprint Performance in Professional Rugby Players: A Randomized, Placebo-Controlled, Double-Blind Intervention Study. The effect of vitamin D2 supplementation on muscle strength in early postmenopausal women: a randomized, double-blind, placebo-controlled trial Independent and combined effects of calcium-vitamin D3 and exercise on bone structure and strength in older men: an 18-month factorial design randomized controlled trial. Effect of Calcium β-Hydroxy-β-Methylbutyrate (CaHMB), Vitamin D, and Protein Supplementation on Postoperative Immobilization in Malnourished Older Adult Patients With Hip Fracture: A Randomized Controlled Study. A randomized, controlled trial of vitamin D supplementation upon musculoskeletal health in postmenarchal females. A randomized controlled trial of the effects of vitamin D on muscle strength and mobility in older women with vitamin D insufficiency. Vitamin D supplementation improves neuromuscular function in older people who fall.
Objective : Indoor athletes have been shown to be prone to vitamin D3 deficiency . The aim of the study was to examine the acute effects of vitamin D supplementation on muscle function using isokinetic dynamometry . Design : R and omized placebo-controlled , double-blind study . Setting : Institutional . Participants : Adult male white national level judoka athletes ( n = 22 ) who were involved in full-time training . Exclusion criteria were vitamin supplementation , overseas travel to sunny climes , and /or an injury incurred during the last 3 months before testing . Interventions : Subjects were r and omly allocated to the treatment ( 150 000IU vitamin D3 ) or placebo and given blinded supplements by an independent research er . Participants were tested twice , 8 days apart , on a Monday morning before the start of judo training and after 2 days of rest . A 5 to 7 mL of blood sample was collected followed by isokinetic concentric quadriceps and hamstring muscle function assessment s on the right leg at 30 and 200 ° ·s−1 . Main Outcome Measures : Repeated- measures analysis of variance was used to analyze isokinetic muscle force and serum 25(OH)D3 . Regression to the mean was used to examine changes in 25(OH)D3 levels over the study period . Results : The treatment group demonstrated a significant increase in serum 25(OH)D levels ( 34 % , P ⩽ 0.001 ) and muscle strength ( 13 % , P = 0.01 ) between days 1 and 8 . No significant differences were found for the placebo group for the same period . Conclusions : A single bolus of 150 000IU vitamin D3 had a significant positive effect on serum 25(OH)D levels and muscle function in vitamin D insufficient elite indoor athletes . Clinical Relevance : Serum 25(OH)D3 levels of indoor athletes should be monitored throughout the year and especially during winter months . Beneficial responses , in muscle strength and serum 25(OH)D3 , to 1 dose of vitamin D3 supplementation can be observed within 1 week of ingestion . Muscle strength is linked to serum 25(OH)D levels Vitamin D insufficiency and hyperparathyroidism have been associated with reduced muscle strength , physical performance , postural stability , well-being , and quality of life . In a double-blinded , r and omized placebo-controlled trial , we aim ed to investigate effects of vitamin D3 supplementation on above-mentioned outcomes in healthy community-dwelling postmenopausal women with plasma levels of 25-hydroxyvitamin D ( 25(OH)D ) below < 50 nmol/l and high parathyroid hormone ( PTH ) levels . Participants ( N = 81 ) were 1:1 treated with vitamin D3  , 70 µg ( 2800 IU)/day or identical placebo for three months during wintertime ( 56 ° N ) . Vitamin D3 supplementation  increased levels of 25(OH)D and 1,25(OH)2D by 230 % ( 95 % CI 189 to 272)% , p < 0.001 and 58 % ( 190 to 271 % ) , p < 0.001 , respectively , and reduced PTH by 17 % ( − 23 to − 11 % ) , p < 0.001 . Compared with placebo , vitamin D3 significantly reduced maximal h and grip strength by 9 % ( − 15 to − 3 % ; p < 0.01 ) and knee flexion strength by 13 % ( − 24 to − 2 % ; p = 0.02 ) and increased the time spent on performing the Timed Up and Go test by 4.4 % ; ( 0.1–8.6 % ; p < 0.05 ) . Levels of physical activity , total lean body mass , appendicular lean mass index , postural stability , well-being , and quality of life did not change in response to treatment . Compared with placebo , a daily supplement with a relatively high dose of vitamin D3 had no beneficial effects on any outcomes . In some measures of muscle strength and physical performance , we even saw a small unfavorable effect . Our data call for caution on use of relatively high daily doses of vitamin D3 in the treatment of vitamin D insufficiency Objectives : We tested the hypothesis that daily vitD3 supplementation increases neuromuscular motor skills , jump power , jump energy , muscular force , and muscular strength . Methods : This was a secondary analysis of a r and omized controlled trial of 12-months of oral 7,000 IU/day vitD3 supplementation or placebo among 56 persons living with HIV aged 9 - 25 years .  Neuromuscular motor skills were quantified using the Bruininks-Oseretsky Test of Motor Proficiency . Power was quantified using peak jump power , and energy was quantified using peak jump height . Muscular force was quantified using isometric ankle plantar- and dorsiflexion , isokinetic knee flexion and extension . Muscular strength was quantified using isometric h and grip strength . Results : After 12-months , serum 25-hydroxyvitamin D [ 25(OH)D ] was higher with supplementation versus placebo ( β=12.1 ng/mL ; P<0.001 ) . In intention-to-treat analyses , supplementation improved neuromuscular motor skills  versus placebo ( β=1.14 ; P=0.041 ) . We observed no effect of supplementation on jump power , jump energy , muscular force , or muscular strength outcomes versus placebo . Conclusions : Among HIV-infected children and young adults supplementation with daily high-dose vitD3 increased concentration of serum 25(OH)D and improved neuromuscular motor skills versus placebo Abstract Incidence of vitamin D deficiency is increasing worldwide . The purpose of this study was to determine if supplementation with vitamin D2 from Portobello mushroom powder would enhance skeletal muscle function and attenuate exercise-induced muscle damage in low vitamin D status high school athletes . Participants were r and omised to Portobello mushroom powder ( 600 IU/d vitamin D2 ) or placebo for 6 weeks . Participants then completed a 1.5-h exercise session design ed to induce skeletal muscle damage . Blood sample s and measures of skeletal muscle function were taken pre-supplementation , post-supplementation/pre-exercise and post-exercise . Six weeks supplementation with vitamin D2 increased serum 25(OH)D2 by 9.9-fold and decreased serum 25(OH)D3 by 28 % . Changes in skeletal muscle function and circulating markers of skeletal muscle damage did not differ between groups . In conclusion , 600 IU/d vitamin D2 increased 25(OH)D2 with a concomitant decrease in 25(OD)D3 , with no effect on muscular function or exercise-induced muscle damage in high school athletes Purpose Vitamin D inadequacy is a global health concern in athletes as well as the general population . Whilst the role of vitamin D in skeletal health is well defined , there remains uncertainty over whether vitamin D supplementation has an added benefit beyond bone health . Methods This r and omised placebo-controlled trial in healthy male and female Gaelic footballers ( n = 42 ) investigated the effect of vitamin D3 supplementation [ 3000 IU ( 75 µg ) daily for 12 weeks , via an oral spray solution ] on VO2 max which was the primary outcome measure . Secondary outcomes included skeletal muscle and lung function . Results Supplementation significantly increased total 25-hydroxyvitamin D concentrations compared to the placebo group ( mean ± SD change from baseline , 36.31 ± 32.34 vs. 6.11 ± 23.93 nmol/L , respectively ; P = 0.006 ) . At baseline , 50 and 22 % of footballers presented with vitamin D insufficiency ( 31–49 nmol/L ) and deficiency ( < 30 nmol/L ) , respectively . Total 25-hydroxyvitamin D concentration did not significantly correlate with any measure of physical performance . Analysis of covariance ( ANCOVA ) models demonstrated that vitamin D supplementation over 12 weeks had no significant effect on VO2 max ( P = 0.375 ) , vertical jump height ( P = 0.797 ) , left and right h and grip strength ( P = 0.146 and P = 0.266 , respectively ) , forced vital capacity ( P = 0.573 ) or forced expiratory volume at 1 s ( P = 0.665 ) , after adjusting for confounders . The high prevalence of vitamin D inadequacy observed in this cohort of collegiate Gaelic footballers supports the need for vitamin D supplementation during wintertime to avoid being at risk of poor bone health . Conclusions Twelve-week daily supplementation with 3000 IU ( 75 µg ) vitamin D3 successfully resolved deficiency but did not have any significant effect on VO2 max , skeletal muscle or lung function Aims : To investigate the effects of a 6-month supplementation with calcium and cholecalciferol on biochemical parameters and muscle strength of institutionalized elderly . Methods : This prospect i ve , double-blind , placebo-controlled , r and omized trial included Brazilian institutionalized people ≥60 years of age receiving a 6-month supplementation ( December to May ) of daily calcium plus monthly placebo ( calcium/placebo group ) or daily calcium plus oral cholecalciferol ( 150,000 IU once a month during the first 2 months , followed by 90,000 IU once a month for the last 4 months ; calcium/vitamin D group ) . Fasting blood sample s for 25(OH)D , PTH and calcium determination were collected ( n = 56 ) and muscle tests were performed ( n = 46 ) to measure the strength of hip flexors ( SHF ) and knee extensors ( SKE ) before ( baseline ) and after the 6-month intervention ( 6 months ) . Results : Due to seasonal variations , serum 25(OH)D significantly enhanced in both groups after treatment , but the calcium/vitamin D group had significantly higher 25 (OH)D levels than the calcium/placebo group ( 84 vs. 33 % , respectively ; p < 0.0001 ) . No cases of hypercalcemia were observed . While the calcium/placebo group showed no improvement in SHF and SKE at 6 months ( p = 0.93 and p = 0.61 , respectively ) , SHF was increased in the calcium/vitamin D group by 16.4 % ( p = 0.0001 ) and SKE by 24.6 % ( p = 0.0007 ) . Conclusions : The suggested cholecalciferol supplementation was safe and efficient in enhancing 25(OH)D levels and lower limb muscle strength in the elderly , in the absence of any regular physical exercise practice CONTEXT Studies examining whether vitamin D supplementation increases muscle mass or muscle-specific vitamin D receptor ( VDR ) concentration are lacking . OBJECTIVE Our objective was to determine whether vitamin D₃ 4000 IU/d alters muscle fiber cross-sectional area ( FCSA ) and intramyonuclear VDR concentration over 4 months . DESIGN AND SETTING This was a r and omized , double-blind , placebo-controlled study in a single center . PARTICIPANTS Participants were 21 mobility-limited women ( aged ≥ 65 years ) with serum 25-hydroxyvitamin D ( 25OHD ) levels of 22.5 to 60 nmol/L. MAIN OUTCOME MEASURES Baseline and 4-month FCSA and intramyonuclear VDR were measured from vastus lateralis muscle cross-sections probed for muscle fiber type ( I/IIa/IIx ) and VDR using immunofluorescence . RESULTS At baseline , mean ( ±SD ) age was 78 ± 5 years ; body mass index was 27 ± 5 kg/m² , 25OHD was 46.3 ± 9.5 nmol/L , and  a short physical performance battery score was 7.95 ± 1.57 out of 12 . At 4 months , 25OHD level was 52.5 ± 17.1 ( placebo ) vs 80.0 ± 11.5 nmol/L ( vitamin D [ VD ] ; P < .01 ) , and change in 25OHD level was strongly associated with percent change in intramyonuclear VDR concentration-independent of group ( r = 0.87 , P < .001 ) . By treatment group , percent change in intramyonuclear VDR concentration was 7.8 % ± 18.2 % ( placebo ) vs 29.7 % ± 11.7 % ( VD ; P = .03 ) with a more pronounced group difference in type II vs I fibers . Percent change in total ( type I/II ) FCSA was -7.4 % ± 18.9 % ( placebo ) vs 10.6 % ± 20.0 % ( VD ; P = .048 ) . CONCLUSION Vitamin D₃ supplementation  increased intramyonuclear VDR concentration by 30 % and increased muscle fiber size by 10 % in older , mobility-limited , vitamin D-insufficient women . Further work is needed to determine whether the observed effect of vitamin D on fiber size is mediated by the VDR and to identify which signaling pathways are involved CONTEXT R and omized control trials ( RCT ) of the effect of vitamin D/calcium supplementation on skeletal muscle strength have not shown promising effect in the elderly . OBJECTIVE Our objective was to assess the effect of vitamin D and /or calcium on muscle strength in young adults with vitamin D deficiency . DESIGN AND SETTING We conducted a RCT using a factorial design at a tertiary-care center from September 2010 to April 2011 . SUBJECTS A total of 173 healthy females with mean age , body mass index , and 25-hydroxyvitamin D [ 25(OH)D ] of 21.7 ± 4.4 yr , 20.8 ± 2.96 kg/m(2 ) , and 9.3 ± 3.37 ng/ml , respectively , were block r and omized to 1 ) double placebo , 2 ) calcium/placebo , 3 ) cholecalciferol/placebo , and 4 ) cholecalciferol/calcium for 6 months . Cholecalciferol was given at 60,000 IU/wk for 8 wk followed by 60,000 IU/fortnight . Elemental calcium was given in doses of 500 mg twice per day for 6 months . METHODS Assessment included h and grip ( primary outcome ) and pinch grip strength , distance walked in 6 min , dyspnea score , quality of life by Short Form ( 36 ) Health Survey ( SP-36 ) , serum 25(OH)D , 1,25-dihydroxyvitamin D , and intact PTH . RESULTS The serum 25(OH)D increased significantly to 29.9 ± 8.35 and 27.0 ± 9.54 ng/ml in two groups on cholecalciferol . The mean h and grip strength ( 19.4 ± 3.92 , 21.1 ± 3.31 , 20.6 ± 3.92 , and 20.1 ± 4.00 kg ) and its increase from baseline ( 0.3 ± 2.25 , 0.3 ± 2.64 , -0.3 ± 2.41 , and 0.6 ± 2.30 kg ) were comparable in four groups at 6 months . Quality of life , urinary calcium/creatinine ratio , and adverse effects were also comparable in groups . CONCLUSION Oral cholecalciferol/calcium supplementation in the dose/schedule used is effective and safe in increasing and maintaining serum 25(OH)D. However , this does not lead to improved skeletal muscle strength in young females Objective To observe the effects of enhanced exercise and combined vitamin D and calcium supplementation on muscular strength and fracture occurrence in postmenopausal women with a high risk of osteoporosis . Methods Totally 614 postmenopausal women at high risk factors of osteoporosis were enrolled in Dongcheng district of Beijing and r and omized into four groups : group A(control group , n=173),group B(regular Tai Chi exercise , n=171),group C(calcium 600 mg/d+VitD3 800 U/d , n=139 ) , and group D[calcium 600 mg/d+25 hydroxyl vitamin D(25OHD ) 0.25 μg/d , n=131].Muscular strength was measured at baseline and one and two years after intervention . Bone turnover markers were measured at baseline and during the two-year follow-up . Falls and fractures were recorded . Results The incidence of 25OHD<50 nmol/L was approximately 92.6%.During the follow-up , the left grip strength decreased significantly two years after intervention(t=-3.252,P=0.001)in group A.Right grip strength decreased significantly in group B(t=2.460,P=0.015)while left grip strength improved significantly in group C(t=-2.051,P=0.043)one year after intervention . In group D , muscular strength in both 12-month and 24-month did not change compared with baseline(both P>0.05).Furthermore , serum procollagen type I N-terminal propeptide elevated significantly in group A(t=-2.962,P=0.004),group B(t=-2.888,P=0.005 ) , and group C(t=-2.441,P=0.016),whereas β-C-terminal telopeptide of type I collagen decreased significantly in group B(t=2.285,P=0.024 ) and group D(t=2.596,P=0.011)two years after intervention . Conclusion Enhanced exercise and combined calcium vitamin D supplementation may help sustain muscle strength in postmenopausal women , while calcium and vitamin D supplementation may improve muscular strength within a short period of time Background Vitamin D deficiency is common in the general public and athletic population s and may impair skeletal muscle function . We therefore assessed the effects of vitamin D3 supplementation on serum 25[OH]D concentrations and physical performance . Methods 30 club-level athletes were block r and omised ( using baseline 25[OH]D concentrations ) into one of three groups receiving either a placebo ( PLB ) , 20 000 or 40 000 IU/week oral vitamin D3 for 12 weeks . Serum 25[OH]D and muscle function ( 1-RM bench press and leg press and vertical jump height ) were measured presupplementation , 6 and 12 weeks postsupplementation . Vitamin D deficiency was defined in accordance with the US Institute of Medicine guideline ( < 50 nmol/l ) . Results 57 % of the subject population were vitamin D deficient at baseline ( mean±SD value 51±24 nmol/l ) . Following 6 and 12 weeks supplementation with 20 000 IU ( 79±14 and 85±10 nmol/l , respectively ) or 40 000 IU vitamin D3 ( 98±14 and 91±24 nmol/l , respectively ) , serum vitamin D concentrations increased in all participants , with every individual achieving concentrations greater than 50 nmol/l . In contrast , vitamin D concentration in the PLB group decreased at 6 and 12 weeks ( 37±18 and 41±22 nmol/l , respectively ) . Increasing serum 25[OH]D had no significant effect on any physical performance parameter ( p>0.05 ) . Conclusions Both 20 000 and 40 000 IU vitamin D3 supplementation over a 6-week period elevates serum 25[OH]D concentrations above 50 nmol/l , but neither dose given for 12 weeks improved our chosen measures of physical performance Vitamin D insufficiency is common in athletes and may lower physical performance . Many cross-sectional studies associate vitamin D status with physical performance in athletes ; however , there have been few prospect i ve r and omized controlled trials with adequate statistical power to test this relationship , and none in the southern hemisphere . Thus , a prospect i ve double-blind , r and omized , placebo-controlled intervention trial was conducted involving 57 professional rugby union players in New Zeal and . Participants were r and omized to receive 50,000 IU of cholecalciferol ( equivalent to 3,570 IU/day ) or placebo once every two weeks over 11 - 12 weeks . Serum 25(OH)D concentrations and physical performance were measured at baseline , weeks 5 - 6 , and weeks 11 - 12 . Mean ( SD ) serum 25(OH)D concentrations for all participants at baseline was 94 ( 18 ) nmol/L , with all players above 50 nmol/L. Vitamin D supplementation significantly increased serum 25(OH)D concentrations compared to placebo , with a 32 nmol/L difference between groups at 11 - 12 weeks ( 95 % CI , 26 - 38 ; p < 0.001 ) . Performance in five of the six tests at study completion , including the primary outcome variable of 30-m sprint time , did not differ between the vitamin D supplemented and placebo groups ( p > 0.05 ) . Performance on the weighted reverse-grip chin up was significantly higher in players receiving vitamin D compared with placebo , by 5.5 kg ( 95 % CI , 2.0 - 8.9 ; p = 0.002 ) . Despite significantly improving vitamin D status in these professional rugby union players , vitamin D supplementation had little impact on physical performance outcomes . Thus , it is unlikely that vitamin D supplementation is an ergogenic aid in this group of athletes Abstract Background : Low serum 25-hydroxyvitamin D [ 25(OH)D ] has been shown to be associated with low muscle mass and loss of muscle strength , result ing in increased disability and frailty in older men and women . Vitamin D deficiency is common in postmenopausal women . The primary objective of the present study was to evaluate the effects of vitamin D supplementation on muscle strength in early postmenopausal women . The effects of vitamin D2 supplementation on muscle mass and muscle cross-sectional area ( CSA ) were secondarily investigated . Methods : A 12-week , prospect i ve , r and omized , double-blind , placebo-controlled trial was conducted in early postmenopausal women ( 45–60 years old ) with vitamin D deficiency ( serum 25(OH)D < 20 ng/ml ) . A total of 88 subjects were r and omized into group I : vitamin D2 supplement 40 000 IU/week ( n = 44 ) , or group II : placebo ( n = 44 ) . Serum 25(OH)D level , muscle strength , muscle mass and muscle CSA were assessed at baseline and 12 weeks after the supplementation . Results : After 12 weeks of supplementation , 70 % of women in group I achieved a sufficient level of serum 25(OH)D ( > 30 ng/ml ) . There were significant differences in changes of serum 25(OH)D levels between the two groups ( p < 0.05 ) . Muscle strength and muscle CSA in group I increased significantly after 12 weeks ( p = 0.015 , 0.045 , respectively ) . However , there were no significant differences in the mean changes of muscle strength , muscle mass and muscle CSA between the two groups ( p = 0.16 , 0.89 , 0.84 , respectively ) . Conclusion : In this study , we found no obvious effect of vitamin D supplementation on the changes in muscle strength , muscle mass and muscle CSA when compared to placebo . However , there were significant changes in muscle strength and muscle CSA from baseline in the vitamin D supplementation group CONTEXT Exercise and calcium-vitamin D are independently recognized as important strategies to prevent osteoporosis , but their combined effects on bone strength and its determinants remain uncertain . OBJECTIVE To assess whether calcium-vitamin D(3 ) fortified milk could enhance the effects of exercise on bone strength , structure , and mineral density in middle-aged and older men . DESIGN , SETTING , PARTICIPANTS An 18-month factorial design r and omized controlled trial in which 180 men aged 50 - 79 years were r and omized to the following : exercise + fortified milk ; exercise ; fortified milk ; or controls . Exercise consisted of progressive resistance training with weight-bearing impact activities performed 3 d/week . Men assigned to fortified milk consumed 400 ml/d of 1 % fat milk containing 1000 mg/d calcium and 800 IU/d vitamin D(3 ) . MAIN OUTCOME MEASURES Changes in bone mineral density ( BMD ) , bone structure , and strength at the lumbar spine ( LS ) , proximal femur , mid-femur , and mid-tibia measured by dual energy x-ray absorptiometry and /or quantitative computed tomography . RESULTS There were no exercise-by-fortified milk interactions at any skeletal site . Main effect analysis showed that exercise led to a 2.1 % ( 95 % confidence interval , 0.5 - 3.6 ) net gain in femoral neck section modulus , which was associated with an approximately 1.9 % gain in areal BMD and cross-sectional area .  Exercise also improved LS trabecular BMD [ net gain 2.2 % ( 95 % confidence interval , 0.2 - 4.1 ) ] , but had no effect on mid-femur or mid-tibia BMD , structure , or strength . There were no main effects of the fortified milk at any skeletal site . CONCLUSION A community-based multi-component exercise program successfully improved LS and femoral neck BMD and strength in healthy older men , but providing additional calcium-vitamin D(3 ) to these replete men did not enhance the osteogenic response BACKGROUND Nutrition support in orthopedic patients with malnutrition shortens the immobilization period . The efficacy of calcium β-hydroxy-β-methylbutyrate ( CaHMB ) , vitamin D , and protein intake on bone structure is studied and well known ; however , there is no evidence supporting the effect of combined use in orthopedic conditions . We investigated the effects of CaHMB , vitamin D , and protein supplementation on wound healing , immobilization period , muscle strength , and laboratory parameters . MATERIAL S AND METHODS This r and omized controlled study included 75 older female patients with a hip fracture admitted to orthopedic clinics . The control group received st and ard postoperative nutrition . The study group received an enteral product containing 3 g CaHMB , 1000 IU vitamin D , and 36 g protein , in addition to st and ard postoperative nutrition . Anthropometric , laboratory , wound-healing , immobilization period , and muscle strength assessment s were evaluated preoperatively and on postoperative days 15 and 30 . RESULTS Wound-healing period was significantly shorter in the CaHMB/vitamin D/protein group than in the control group ( P < .05 ) . The number of patients in the CaHMB/vitamin D/protein group who were mobile on days 15 and 30 ( 81.3 % ) was significantly higher than patients in the control group , who were mobile on days 15 and 30 ( 26.7 % ) ( P = .001 ) . Muscle strength on day 30 was significantly higher in the CaHMB/vitamin D/protein group vs the control group . CONCLUSION Nutrition of elderly patients  with a CaHMB/vitamin D/protein combination led to acceleration of wound healing , shortening of immobilization period , and increased muscle strength without changing body mass index . It also reduced dependence to bed and related complications after an orthopedic operation CONTEXT There has been a resurgence of vitamin D deficiency rickets throughout the developed world , with infants and adolescents being primarily affected . Adolescence is a crucial period for muscle and bone mineral accumulation . OBJECTIVE The aim was to determine the effect of vitamin D supplementation on the adolescent musculoskeletal system . DESIGN AND SETTING We conducted a community-based , double-blind , r and omized controlled trial in a secondary school . PARTICIPANTS Postmenarchal 12- to 14-yr-old females participated in the trial . Ninety-nine were screened , 73 were included in r and omized controlled trial , and 69 completed the trial . There were no adverse events . INTERVENTION Four doses of 150,000 IU vitamin D(2 ) ( ergocalciferol ) were given over 1 yr . MAIN OUTCOME MEASURES Dual-energy x-ray absorptiometry , peripheral quantitative computed tomography , and jumping mechanography were used . RESULTS At follow-up , 25-hydroxyvitamin D [ 25(OH)D ] status was 56.0 ± 8.9 nmol/liter in the intervention group and 15.8 ± 6.6 nmol/liter in controls . There were no effects of supplementation on bone ; however , for muscle function , efficiency of movement improved in the vitamin D-treated group . There was an interaction between baseline 25(OH)D concentration and response to vitamin D supplementation for muscle jump velocity . CONCLUSIONS Despite improvements in 25(OH)D status , treatment with vitamin D(2 ) was not shown to increase mineral accretion , bone geometry or strength , muscle force , or power . There were greater increases in jump velocity in girls with the lowest baseline 25(OH)D concentrations . Lack of effect of intervention after the period of peak mineral and muscle mass accretion suggests that earlier action is required OBJECTIVES To evaluate the effects of vitamin D treatment on muscle strength and mobility in older women with vitamin D insufficiency . DESIGN One-year population -based , double-blind , r and omized , controlled trial . SETTING Perth , Australia ( latitude 32 ° S ) . PARTICIPANTS Three hundred two community-dwelling ambulant elderly women aged 70 to 90 with a serum 25-hydroxyvitamin D ( 25(OH)D ) concentration less than 24 ng/mL. INTERVENTION Vitamin D(2 ) 1,000 IU/d or identical placebo ; calcium citrate ( 1 g calcium/d ) in both groups . MEASUREMENTS Lower limb muscle strength and mobility as assessed using the Timed Up and Go Test ( TUAG ) . RESULTS At baseline , mean ± st and ard deviation serum 25(OH)D was 17.7 ± 4.2 ng/mL ; this increased to 24.0 ± 5.6 ng/mL in the vitamin D group after 1 year but remained the same in the placebo group . For hip extensor and adductor strength and TUAG , but not for other muscle groups , a significant interaction between treatment group and baseline values was noted . In those with baseline values in the lowest tertile , vitamin D  improved muscle strength and TUAG more than calcium alone ( mean ( st and ard error ) : hip extensors 22.6 % ( 9.5 % ) ; hip adductors 13.5 % ( 6.7 % ) , TUAG 17.5 % ( 7.6 % ) , P < .05 ) . Baseline 25(OH)D levels did not influence patient response to supplementation . CONCLUSION Vitamin D therapy was observed to increase muscle function in those who were the weakest and slowest at baseline . Vitamin D should be given to people with insufficiency or deficiency to improve muscle strength and mobility BACKGROUND vitamin D supplementation reduces the incidence of fractures in older adults . This may be partly mediated by effects of vitamin D on neuromuscular function . OBJECTIVE to determine the effects of vitamin D supplementation on aspects of neuromuscular function known to be risk factors for falls and fractures . DESIGN r and omised , double-blind , placebo-controlled study . SETTING falls clinic taking referrals from general practitioners and accident and emergency department . SUBJECTS 139 ambulatory subjects ( > /=65 years ) with a history of falls and 25-hydroxyvitamin D ( 25OHD ) < /=12 microg/l . INTERVENTION patients were r and omised to receive a single intramuscular injection of 600,000 i.u . ergocalciferol or placebo . OUTCOME MEASURES assessment s including biochemistry , postural sway , choice reaction time ( CRT ) , aggregate functional performance time ( AFPT ) , and quadriceps strength were carried out at baseline and 6 months post-intervention . RESULTS baseline characteristics were comparable between both groups . 25OHD in the treatment group increased significantly at 6 months . AFPT deteriorated in the control group and improved in the intervention group , representing a significant difference between groups ( + 6.6 s versus -2.0 s , t = 2.80 , P < 0.05 ) . Similar changes were observed for CRT ( -0.06 s versus + 0.41 s , t = -2.52 , P < 0.01 ) and postural sway ( + 0.0025 versus -0.0138 , t = 2.35 , P < 0.02 ) . There was no significant difference in muscle strength change between groups ( -10 N versus -2 N , t = -1.26 , ns ) . A significant correlation between change in AFPT and change in 25OHD levels was observed ( r = 0.19 , P = 0.03 ) . There was no significant difference in the number of falls ( 0.39 versus 0.24 , t = 1.08 , P = 0.28 ) or fallers ( 14 versus 11 , P = 0.52 ) between two groups . CONCLUSIONS vitamin D supplementation , in fallers with vitamin D insufficiency , has a significant beneficial effect on functional performance , reaction time and balance , but not muscle strength . This suggests that vitamin D supplementation improves neuromuscular or neuroprotective function , which may in part explain the mechanism whereby vitamin D reduces falls and fractures
Conclusion Although , serum 25(OH)D concentrations after supplementation reached sufficiency was observed , muscle strength did not significantly improve at this point of current meta- analysis .
Background The purpose of this systematic review and meta- analysis is to investigate the effects of vitamin D3 supplementation on skeletal muscle strength in athletes .
Vitamin D3 supplements or vitamin D3 fortified foods always have cl aims for bringing people health benefits including bone and muscle health .
An up-to- date rigorous systematic review and meta- analysis is important to better underst and the effect of vitamin D3 supplementation on muscle strength .