Isoflavone supplementation plus combined aerobic and resistance exercise do not change phase angle values in postmenopausal women: A randomized placebo-controlled clinical trial

Abstract

Objective: The aim of this study was to evaluate the effect of isoflavone supplementation plus combined exercise protocol on phase angle (PhA) values in postmenopausal women.

Methods: Thirty postmenopausal women were randomly assigned in a double blind, placebo-controlled clinical trial divided into two groups: 100 mg/day of isoflavone supplementation (n = 16) and 100 mg/day of starch (placebo; n = 14). In addition, both groups performed a combined aerobic and resistance exercise during 10 weeks. Body composition and PhA were evaluated by bioelectrical impedance.

Results: PhA values did not change in the isoflavone group (PRE: 6.7 ± 0.7° to POST: 6.7 ± 0.6°) and in the placebo group (PRE: 7.2 ± 1.0° to POST: 6.8 ± 0.5°); p group = 0.304, p time = 0.227, p group x time interaction = 0.137. Additionally, delta values were not different (0.04 ± 0.5° vs. -0.40 ± 0.99°; p = 0.176) between isoflavone and placebo groups, respectively.

Conclusion: We conclude that isoflavone supplementation plus combined aerobic and resistance exercise did not change PhA in postmenopausal women. The patients were part of ClinicalTrials.gov: NCT03008785.

Keywords: Body composition; Exercise; Isoflavone; Muscle function; Strength; Supplementation.