The effects of dietary licorice flavonoid oil supplementation on body balance control in healthy middle-aged and older Japanese women undergoing a physical exercise intervention: a randomized, double-blind, placebo-controlled trial

Abstract

Aims In this study, the effects of licorice flavonoid oil (LFO) supplementation on mobility functions were evaluated in middle-aged and older women who underwent daily physical exercise. Methods The 73 women aged 59-85 years (71.2 +/- 5.2 years) were randomly assigned to the LFO group (n = 37) or the placebo group (n = 36). For 16 weeks, the LFO group consumed a daily capsule containing 300 mg of LFO, while the placebo group consumed a placebo capsule. All participants were instructed to complete a strength training program during the 16 weeks and to increase their daily step count by 1000. 10-m walking speed (with/no obstruction), one-leg standing time with eyes open, handgrip strength, isometric knee extension strength, and body composition were evaluated at baseline and every eight weeks. Results In the 10-m walking speeds (with/no obstruction), LFO supplementation did not show significant improvements. One-leg standing time was significantly prolonged with LFO intake (LFO: baseline 73.9 s vs 16 weeks 93.5, placebo: baseline 82.8 vs 16 weeks 87.1,p = 0.03). In addition, a significant decrease in BMI and body fat percentage with LFO was found (p = 0.01,p = 0.03, respectively). Discussion Since a lower BMI corresponds to a lighter physical load on the lower limb, in addition, since LFO might improve skeletal muscle function by antioxidant activity, participants could stand longer and body balance control was improved. Conclusion LFO supplementation improved body balance control and may contribute to fall prevention in healthy middle-aged and older women having daily physical exercise.