For example, Orces analyzed 2205 Ecuadorians aged 60 or older and found that men and women with grip strength < 26kg and < 16kg, respectively, had a 31% and 43% greater likelihood of having low serum 25D concentrations in models controlled by age, race, schooling, BMI, area of residence, smoking habit, consumption of dairy products, level of physical activity and number of diseases []. Similarly, Aspell et al.
Vitamin D participates in both biochemical processes for the maintenance of muscle mass and muscle contraction kinetics. Through its genomic effects, vitamin D exerts an influence on the expression of contractile proteins and differentiation of muscle fibers, which affects the quantity of muscle mass. Through its non-genomic effects, it participates in the regulation and transport of calcium, which exerts an influence on muscle contraction kinetics.