Effect of a resistance-power training and vitamin D supplementation on serum IGF-1 concentration and physical function in elderly women

This study was aimed to evaluate the effect of a period of resistance-power training and vitamin D supplementation on serum insulin-like growth factor 1 (IGF-1) concentration and physical function in elderly women.

44 elderly women volunteered and were randomly divided into four groups of training + placebo (TP), training + vitamin D (TS), vitamin D (vit D) and placebo (P). The training groups performed a weight training program for 12 weeks (three sessions per week). People in the Vitamin D group took one 50,000 IU vitamin D jelly tablet every two weeks, and the P group took one placebo capsule (rice flour). Blood samples were taken from all subjects before and after the training and measured serum Vitamin D and IGF-1. Physical function indices were also measured. Data were analyzed using SPSS 25 and R3.5.2 software, and analysis of variance of weighted repeated measures.

Serum vitamin D was significantly increased in TS and vit D groups compared to control group, while it was significantly decreased in TP group (p ≤ 0.05). Training and supplementation interventions had not significant effects on serum IGF-1 (p ≥ 0.05). There was a significant increase between physical function indices in the TS and TP groups compared to the control group (p ≤ 0.05), while there was no significant difference between the two groups.

Performing resistance-power training in the elderly improved the physical function indices; however adding vitamin D supplementation to the trainings did not had a greater effect on physical function.