Impact of vitamin D supplementation during a resistance training intervention on body composition, muscle function, and glucose tolerance in overweight and obese adults

Abstract

Background & Aims The impact of vitamin D supplementation in overweight and obese adults during resistance training on body composition, muscle function, and glucose tolerance was investigated. Methods Twenty-three overweight and obese (age: 26.1±4.7 y; BMI: 31.3±3.2 kg/m2; 25-hydroxyvitamin D: 19.3±7.2 ng/mL) adults were recruited for participation in a double-blind, placebo-controlled trial. Participants were randomly divided into vitamin D (VitD, 4000 IU/d; 5 female, 5 male) and placebo (PL; 7 female, 6 male) groups. Both groups completed 12 wks of resistance training. 25-hydroxyvitamin D, parathyroid hormone, body composition, and glucose tolerance were assessed at baseline and 12 wks. Muscle function (strength and power) was assessed at baseline, 4, 8, and 12 wks. Results During the intervention, 25-hydroxyvitamin D increased and parathyroid hormone decreased in the VitD group (P<0.05). Peak power was significantly increased at 4 wks in the VitD group only (P<0.05). Regression analysis revealed an inverse association between the change in 25-hydroxyvitamin D with the change in waist-to-hip ratio (R2=0.205, P=0.02). No other improvements were observed with supplementation. Conclusions Vitamin D supplementation in overweight and obese adults during resistance training induced an early improvement in peak power, and elevated vitamin D status was associated with reduced waist-to-hip ratio. Clinical trial registration number NCT01199926

Serum Parathyroid Hormone Responses to Vitamin D Supplementation in Overweight/Obese Adults: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

“…As a result, a total of 18 publications were included in this report, with 11 of them being included in the meta-analysis of PTH responses by vitamin D supplementation, three included in the analysis of PTH responses by vitamin D and calcium supplementation, and the other four being analyzed qualitatively. Table 1 [16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33] shows the publications included in this report in the order they were retrieved. The table lists the sample size, mean BMI, mean change in PTH and 25OHD, as well as baseline and end of study results for PTH and 25OHD.…”

“…For determining the responses of PTH due to combined vitamin D-calcium supplementation, two studies that examined three different groups of overweight and obese participants that met the inclusion criteria were included in the meta-analysis (total N = 337, Figure 6) [27,33]. The Cochran’s Q was significant, Q(2) = 146.59, p < 0.001.…”

Interplay of vitamin D and metabolic syndrome: A review

“…Carrillo et al [49], demonstrated impact of supplementation of vitamin D during resistance training in 24 overweight and obese individuals. Intervention group who received vitamin D at the rate of 4000 IU per day against placebo, reported elevated vitamin D status was associated with reduced waist-to-hip ratio.…”

“…Intervention group who received vitamin D at the rate of 4000 IU per day against placebo, reported elevated vitamin D status was associated with reduced waist-to-hip ratio. The study revealed higher efficiency of vitamin D in lowering complications of obesity as compared to physical exercise [49]. Significant reduction in serum vitamin D concentration and secondary hyperparathyroidism was observed in severely obese patients following jejunal bypass surgery [50].…”

Supplemental vitamin D increases serum cytokines in those with initially low 25-hydroxyvitamin D: A randomized, double blind, placebo-controlled study

“…Although supplemental vitamin D increases serum 25(OH)D, results regarding the influence of supplementation on muscle strength and physical performance are inconsistent [24][25][26][27][28][29][30]. In a previous investigation, supplemental vitamin D (4000 IU/d of cholecalciferol) enhanced strength recovery following (Post to 24-h) an exercise protocol that induced immediate and persistent deficits in muscle strength [31].…”