Testosterone responses after resistance exercise in women: Influence of regional fat distribution

ArticleinInternational journal of sport nutrition and exercise metabolism 11(4):451-65 · January 2002with31 Reads
Source: PubMed
Regional fat distribution (RFD) has been associated with metabolic derangements in populations with obesity. For example, upper body fat patterning is associated with higher levels of free testosterone (FT) and lower levels of sex-hormone binding globulin (SHBG). We sought to determine the extent to which this relationship was true in a healthy (i.e., non-obese) female population and whether RFD influenced androgen responses to resistance exercise. This study examined the effects of RFD on total testosterone (TT), FT, and SHBG responses to an acute resistance exercise test (ARET) among 47 women (22+/-3 years; 165+/-6 cm; 62+/-8 kg; 25+/-5%BF; 23+/-3 BMI). RFD was characterized by 3 separate indices: waist-to-hip ratio (WHR), ratio of upper arm fat to mid-thigh fat assessed with magnetic resonance imaging (MRI ratio), and ratio of subscapular to triceps ratio (SB/TRi ratio). Skinfolds were measured for the triceps, chest, subscapular, mid-axillary, suprailaic, abdomen, and thigh regions. The ARET consisted of 6 sets of 10 RM squats separated by 2-min rest periods. Blood was obtained pre- and post- ARET. TT, FT, and SHBG concentrations were determined by radioimmunoassay. Subjects were divided into tertiles from the indices of RFD, and statistical analyses were performed by an ANOVA with repeated measures (RFD and exercise as main effects). Significant (p < or = .05) increases following the AHRET were observed for TT (approximately 25%), FT (approximately 25%), and SHBG (4%). With multiple regression analysis, anthropometric measures significantly predicted pre- concentrations of FT, post-concentrations of TT, and pre-concentrations of SHBG. The SB/TRi and MRI ratios but not the WHR, were discriminant for hormonal concentrations among the tertiles. In young, healthy women, resistance exercise can induce transient increases in testosterone, and anthropometric markers of adiposity correlate with testosterone concentrations.
    • "2) reported that estrogen receptors might have a role on the response of osteoblasts to exercise. The result demonstrated that testosterone levels increased (31.5 %) in the training group compared with the control group. Findings on the testosterone response in women are equivocal with both increases and no changes observed in response to exercise. Nindl et al. (2001) showed that testosterone level increased in response to an acute resistance exercise test in healthy young women. However, Thomas et al. (2010) noted that salivary testosterone did not change after supra-maximal exercise in female adolescents. Aizawa et al. (2003) also demonstrated that serum testosterone concentrations did not change i"
    [Show abstract] [Hide abstract] ABSTRACT: Physical activity has been proposed as one strategy to enhance bone mineral acquisition; however, the basic mechanisms of this effect are not fully understood. The purpose of this study was to investigate the effect of 12 weeks of resistance training on hormones of bone formation in young sedentary women. Twenty sedentary females (aged 25.3 ± 3.2 years; ±SD) volunteered to participate in this study. The subjects were randomly assigned to a training group (n = 10) or control group (n = 10). Subjects executed eight resistance exercises selected to stress the major muscle groups in the following order: chest press, leg extension, shoulder press, leg curls, latissimus pull down, leg press, arm curls, and triceps extension. Resistance training consisted of 50-60 min of circuit weight training per day, 3 days a week, for 12 weeks. This training was circularly performed in eight stations and included two to four sets with 8-12 maximal repetitions at 65-80 % of one-repetition maximum in each station. After 12 weeks, the training group had a significant increase (P < 0.05) in the growth hormone, estrogen, parathyroid hormone and testosterone compared to the control group. The results showed that insulin-like growth factor I levels did not change significantly in response to resistance training. In conclusion, the results suggest that resistance training with specific intensity and duration utilized in this study increases the hormones of bone formation in young sedentary women.
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    • "MMIs, muscle mass indexes, were expressed as mean ± SD MMIs, muscle mass indexes, were expressed as mean ± SD exercise [3, 5, 11, 20, 36, 37, 42, 48]. The increased plasma TC in male rats during exercise is at least partially a result of lactate's effect on the secretion of testosterone [30, 31], and testosterone may suppress the expression of proinflammatory cytokines such as tumor necrosis factor-alpha and interleukin- 1 [8, 32]. "
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