Effects of anabolic precursors on serum testosterone concentrations and adaptations to resistance training in young men

Exercise Biochemistry Laboratory, Department of Health and Human Performance, Iowa State University, Ames, IA 50011, USA.
International journal of sport nutrition and exercise metabolism (Impact Factor: 2.44). 09/2000; 10(3):340-59.
Source: PubMed


The effects of androgen precursors, combined with herbal extracts designed to enhance testosterone formation and reduce conversion of androgens to estrogens was studied in young men. Subjects performed 3 days of resistance training per week for 8 weeks. Each day during Weeks 1, 2, 4, 5, 7, and 8, subjects consumed either placebo (PL; n = 10) or a supplement (ANDRO-6; n = 10), which contained daily doses of 300 mg androstenedione, 150 mg DHEA, 750 mg Tribulus terrestris, 625 mg Chrysin, 300 mg Indole-3-carbinol, and 540 mg Saw palmetto. Serum androstenedione concentrations were higher in ANDRO-6 after 2, 5, and 8 weeks (p <.05), while serum concentrations of free and total testosterone were unchanged in both groups. Serum estradiol was elevated at Weeks 2, 5, and 8 in ANDRO-6 (p <.05), and serum estrone was elevated at Weeks 5 and 8 (p <.05). Muscle strength increased (p <.05) similarly from Weeks 0 to 4, and again from Weeks 4 to 8 in both treatment groups. The acute effect of one third of the daily dose of ANDRO-6 and PL was studied in 10 men (23 +/- 4 years). Serum androstenedione concentrations were elevated (p <.05) in ANDRO-6 from 150 to 360 min after ingestion, while serum free or total testosterone concentrations were unchanged. These data provide evidence that the addition of these herbal extracts to androstenedione does not result in increased serum testosterone concentrations, reduce the estrogenic effect of androstenedione, and does not augment the adaptations to resistance training.

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    • "HCA is extracted from Garsinia Canbogia and it directly affects fatty acid synthesis, lipogenesis, appetite, and weight control. Therefore, HCA has been combined with other ingredients since the 1990's to produce functional dietary supplements for losing weight, protecting heart function, controlling lipids, and improving endurance [11]. Puer tea including green tea has been reported to have an anticarcinogenic effect and to prevent coronary artery disease in animal studies. "
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    ABSTRACT: Purpose: The purpose of this study was to investigate the effectiveness of a composite weight-loss dietary supplement on body composition and blood lipid changes in middle-aged women. Methods: Thirty seven middle-aged women living in the Kyunggi area participated in this study and they were randomly divided into 2 groups (Dietary supplement ingestion group; DG, n = 20 and Placebo group; PG, n = 17). Blood draw and dual energy x-ray (DEXA) measurements were conducted to examine changes in body composition and blood lipids. Results: There were no significant changes in weight and BMI in both groups. There was an interaction between the composite weight-loss dietary supplement intake and lean body mass in DG and there was a significant decrease in percent body fat in DG. Blood lipid changes in the study results showed that there was no significant difference in TC, TG, and LDL in both groups; however, there was a significant interaction between the composite weight-loss dietary supplement intake and HDL-C as well as an increase in the HDL-C of DG. Conclusion: In conclusion, it seems that 4-week ingestion of the composite weight-loss dietary supplement decreased body fat, increased lean body mass, and increased HDL-C. Therefore, the composite weight-loss dietary supplement is expected to prevent obesity and induce health improvements in middle-aged women.
    11/2015; 19(3):211-6. DOI:10.5717/jenb.2015.15090707
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    • "TT plus AAS. In the search for appropriate androgens taken by athletes, Brown et al. (2000b) focused their attention on exogenous androstenedione and androstenediol, steroids which in the human body are converted into more biologically active compounds. Assuming that TT would enhance the rate of that conversion, and in consequence increase the effectiveness of relatively small amounts of those pro-hormones, the same authors carried out more comprehensive studies on the biological effect of TT taken concurrently with androstenediol (Brown et al., 2001) or androstenedione (Brown et al., 2000a). "
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    Journal of Human Kinetics 06/2014; 41:99-105. DOI:10.2478/hukin-2014-0037 · 1.03 Impact Factor
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    • "Experimental studies using T. terrestris extracts have demonstrated an increase in sexual function in rats which has been attributed to an increase in testosterone, dihydrotestosterone, and dehydroepiandrosterone.[89] One clinical study has also demonstrated that T. terrestris extract increases body's natural testosterone levels and thereby improves male sexual performance and helps build muscle.[10] However, as sexual dysfunction has been shown to be more prevalent in the aging population,[1] the evaluation of investigational drugs in aged and sexually sluggish males for their aphrodisiac and sexual tonic activity is a better predictor for their efficacy in the clinical setting. "
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