Exercise training and burdock root (Arctium lappa L.) extract independently improve abdominal obesity and sex hormones in elderly women with metabolic syndrome

Abstract

The prevalence of metabolic syndrome (MS) is increasing among the elderly, and new lifestyle-based treatment strategies are warranted. We conducted a randomized, double-blind controlled trial of the effects of aquatic exercise (AE) and/or consumption of burdock root extract (BE) on body composition and serum sex hormones, i.e., testosterone, estradiol, sex hormone-binding globulin (SHBG), and dehydroepiandrosterone-sulfate (DHEA-S) in elderly women with MS. The percentage of abdominal fat was decreased in the AE group. Waist circumference was increased in the control (CON) group, but not in the other groups. SHBG and estradiol levels were enhanced by both AE and BE and correlated with changes in fat-related body composition. DHEA-S levels only increased in the BE group, which was consistent with changes in lean body mass. Testosterone levels decreased in the CON group, which correlated with changes in lean body mass, skeletal muscle mass, body fat, and waist circumference. Our findings suggested that the combined AE/BE intervention exerted no synergistic and/or additive effects on any sex-related outcome measures in elderly women with MS.

Figure 1

Changes in abdominal fat percentage and waist circumference. (a) Significant differences were observed between aquatic exercise (AE) and control (CON) subjects in the delta (Δ) values of % abdominal fat (^**p < 0.01). (b) Significant differences were observed between AE + BE (burdock root extract) and CON subjects in the delta (Δ) value of waist circumference (^**p < 0.01). Data are expressed as mean ± SD.

Figure 2

Effects of 16-week aquatic exercise (AE) and burdock root extract (BE) interventions on serum sex hormones. (a) Testosterone levels in the control (CON) group were decreased after the 16-week intervention period (^#p < 0.05). (b) The post-test levels of estradiol were higher in AE (^**p < 0.01) compared to the CON group. (c) Sex hormone-binding globulin (SHBG) levels were increased in both AE (^##p < 0.01) and BE subjects (^#p < 0.05), but not in the AE + BE group. (d) The post-test levels of dehydroepiandrosterone sulfate (DHEA-S) were higher in the BE than in the CON group (*p < 0.05). (e) A significant increase in the delta (Δ) value of testosterone was observed in the AE and AE + BE groups compared to the CON group (^*p < 0.05). (f) A significant increase in the delta (Δ) value of estradiol was detected in AE (^**p < 0.01), BE (^*p < 0.05), and AE + BE women (^*p < 0.05) compared to CON women. (g) A significant increase in the delta (Δ) value of SHBG was observed in the AE and BE groups compared to the CON group (^*p < 0.05). (h) No significant changes in DHEA-S levels were observed between the groups. Data are presented as mean ± SD.

Figure 3

Correlation between body composition indices and sex hormones. (a–e) Δ-testosterone was correlated with Δ-lean body mass, Δ-skeletal muscle mass, Δ-percentage of body fat, Δ-percentage of abdominal fat and, Δ-waist circumference. (f, g) Δ-SHBG (sex hormone-binding globulin) was correlated with Δ-percentage of body fat and Δ-percentage of abdominal fat. (h) A significant correlation was observed between Δ-DHEA-S (dehydroepiandrosterone sulfate) and Δ-lean body mass. Correlation analysis was performed (Pearson’s correlation coefficients). Each circle represents an individual subject (n = 24).