Table 1: Variations in serum vitamin D and dynamic and postural balance over 5 seasons.

VariableEnd of springEnd of summerEnd of autumnEnd of winterEnd of spring

ML sway EO (cm) mean (SD)1.9 (0.7)1.2 (0.6)1.3 (0.5)1.1 (0.5)1.1 (0.5)
Range0.7–5.00.4–3.80.6–2.80.4–3.60.5–2.5
Change from season 1 mean (95% CI) −0.6 (−0.7 to −0.5)*−0.6 (−0.7 to −0.4)*−0.8 (−0.9 to −0.6)*−0.7 (−0.8 to −0.4)*
ML sway EC (cm) mean (SD)2.1 (0.9)1.4 (0.7)1.4 (0.7)1.3 (0.8)1.4 (0.8)
Range0.8–4.70.4–3.80.6–4.20.6–5.20.5–4.9
Change from season 1 mean (95% CI) −0.7 (−0.8 to −0.6)*−0.7 (−0.8 to −0.6)*−0.8 (−0.9 to −0.6)*−0.7 (−0.9 to −0.6)*
Foam ML (cm) sway EO mean (SD)3.8 (1.2)2.8 (1.1)3.0 (1.2)2.4 (0.8)2.6 (0.8)
Range1.0–8.41.1–7.01.2–11.411.2–6.01.1–5.8
Change from season 1 mean (95% CI) −1.0 (−1.2 to −0.7)*−0.8 (−1.0 to −0.5)*−1.2 (−1.5 to −1.0)*−1.2 (−1.4 to −0.9)*
Foam ML (cm) sway EC mean (SD)6.8 (2.7)5.0 (1.7)4.7 (2.1)4.6 (1.9)4.8 (1.9)
Range2.0–28.71.7–10.52.0–14.02.0–11.91.9–16.2
Change from season 1 mean (95% CI) −1.7 (−2.3 to −1.2)*−2.1 (−2.6 to −1.5)*−2.1 (−2.8 to −1.5)*−2.1 (−2.8 to −1.3)*
Serum vitamin D (nmol/L) mean (SD)60 (19)68 (21)*58 (21)52 (21)*59 (20)
Range20–11510–12613–11516–10720–114
Change from season 1 mean (95% CI)8 (6 to 11)−2 (−5 to 1)−8 (−11 to −5)−2 (−5 to 1)

Data presented as mean (SD), changes from season one presented as mean change (95% CI) (adjusted for age, gender strength, and physical activity), *( ), ML: mediolateral, EO: eyes open, EC: eyes closed, cm: centimeter.