Summary of included study outcome measures and significant results
| Author, year | Outcome measures | Significant results | |
| Agergaard et al 31 | Muscle strength Muscle CSA Muscle quality | Isometric knee extensor (strain gauge) MRI of quadriceps muscle (6 mm thick) Muscle strength/CSA | Muscle strength: no between-group difference Muscle CSA: no between-group difference Muscle quality: N/S |
| Bunout et al 32 | Muscle strength Muscle function BMD Body sway Endurance | Quadriceps (table) and hand grip strength (dynamometer) SPPB, TUG Femoral neck and spine (DXA) Romberg ratio Distance walked in 12 min | Muscle strength: increased with exercise (p<0.001), no effect of vitamin D Muscle function: SPPB increased with exercise (p=0.002), no effect of vitamin D, TUG: increased in both groups (p=0.004) BMD: femoral neck increased with vitamin D, decreased without (p=0.006). Spine was N/S Body sway: lower with vitamin D than without (p=0.05) Endurance: N/S |
| Drey et al 33 | Muscle power Muscle function Body composition | Lower limb sit-to-stand transfer power (force plate) SPPB, SF-LLFDI aLM (DXA) | Muscle power: increased with vitamin D intake (p=0.017) Muscle function : SPPB increased with exercise (p=0.009), SF-LLFDI was N/S Body composition: aLM was N/S |
| Gianoudis et al 34 | Muscle strength Muscle power Muscle function BMD Body composition Dynamic balance | Lower limbs (bilateral leg press) Timed stair climb test 30 s sit-to-stand test, TUG Femoral neck and spine (DXA) Total body lean and fat mass (DXA) Four square step test | Muscle strength: intervention increased strength relative to controls (p<0.001) Muscle power: Intervention increased power relative to controls (p<0.05) Muscle function: intervention improved sit-to-stand relative to controls (p<0.05) TUG: no between-group difference BMD: intervention increased femoral neck relative to controls (p<0.05) Spine: intervention increased relative to controls (p<0.05) Body composition: lean and fat mass: N/S Dynamic balance: intervention increased relative to controls (p<0.05) |
| Jessup et al 35 | Muscle strength BMD Body sway | Hand grip (dynamometer), mean of 8 tests (stack machine) Femoral neck and spine (DXA) AccuSway force platform | Muscle strength: increased with intervention (p=0.0156) BMD femoral neck: increase with intervention (p=0.00001) Spine: no between-group difference Body sway: significantly reduced in intervention group (p=0.0027) |
| Uusi-Rasi et al 21 | Muscle strength Muscle function BMD Dynamic balance | Max isometric leg extensor strength at a knee angle of 110° SPPB, TUG Femoral neck and spine (BMD) Backwards walking | Muscle strength: increased with exercise (p<0.001) Vitamin D supplementation N/S Muscle function : SPPB=N/S TUG: vitamin D without exercise increased relative to placebo without exercise (p=0.01) BMD: femoral neck Vitamin D maintained BMD (p=0.02) as did exercise (p=0.01) Spine: N/S Dynamic balance: improved with exercise (placebo: p=0.001, vitamin D: p=0.03). No additive effect of vitamin D |
| Verschueren et al 36 | Muscle strength BMD Muscle mass | Isometric and dynamic knee extensor strength Femoral neck (DXA) Mass of upper leg (multislice CT) | Muscle strength: isometric: N/S Dynamic: N/S Vitamin D=no effect BMD: improved in all groups. No between-group difference Muscle mass: N/S |
aLM, appendicular Lean Mass; BMD, bone mineral density; CSA, cross-sectional area; DXA, dual-energy X-ray absorptiometry; N/S, not significant; SPPB, short physical performance battery; SF-LLFDI, Short Form of the Late-Life Function and Disability Instrument; TUG, timed up and go.