Although endurance exercise and supplemental estrogen have both been shown to improve serum lipid cardiac risk profiles in postmenopausal women, data regarding a possible synergistic influence are scarce and inconsistent. The purpose of this study was to determine whether such a synergistic influence could be demonstrated. Serum concentrations of total cholesterol (TC), HDL-cholesterol (HDL-C), HDL2-C, HDL3-C, LDL-C, and triglycerides (TG) were obtained from postmenopausal women (N = 45) in each of 4 groups: currently exercising and taking estrogen replacement, exercising and not taking estrogen, sedentary and taking estrogen, and sedentary and not taking estrogen. HDL-C was on average 21% higher (p < .05) and the HDL-C:LDL-C ratio on average 45% higher (p < .05) in the exercise-plus-estrogen group than in any of the other 3 groups. It was concluded that the combination of endurance exercise and estrogen replacement might be associated with better lipid coronary risk profiles in postmenopausal women than either intervention alone.
John S. Green, Peter W. Grandjean, Shelly Weise, Stephen F. Crouse and J. James Rohack
Darryn S. Willoughby, Colin Wilborn, Lemuel Taylor and William Campbell
This study examined the effects of an aromatase-inhibiting nutritional supplement on serum steroid hormones, body composition, and clinical safety markers. Sixteen eugonadal young men ingested either Novedex XT™ or a placebo daily for 8 wk, followed by a 3-wk washout period. Body composition was assessed and blood and urine samples obtained at weeks 0, 4, 8, and 11. Data were analyzed by 2-way repeated-measures ANOVA. Novedex XT resulted in average increases of 283%, 625%, 566%, and 438% for total testosterone (P = 0.001), free testosterone (P = 0.001), dihydrotestosterone (P = 0.001), and the testosterone:estrogen ratio (P = 0.001), respectively, whereas fat mass decreased 3.5% (P = 0.026) during supplementation. No significant differences were observed in blood and urinary clinical safety markers or for any of the other serum hormones (P > 0.05). This study indicates that Novedex XT significantly increases serum androgen levels and decreases fat mass.
David R. Bell, Megan P. Myrick, J. Troy Blackburn, Sandra J. Shultz, Kevin M. Guskiewicz and Darin A. Padua
Preventing noncontact ACL injuries has been a major focus of athletic trainers and researchers. One factor that may influence female noncontact ACL injury is the fluctuating concentrations of hormones in the body.
To determine whether muscle properties change across the menstrual cycle.
Repeated measures. Testing was performed within 3 d after the onset of menses and ovulation. Repeated-measures ANOVAs were used to determine changes in variables across the menstrual cycle, and Pearson correlations were used to determine relationships between variables.
8 women with normal menstrual cycles.
Main Outcome Measures:
Active hamstring stiffness and hamstring extensibility.
Hamstring extensibility (P = .003) increased at the ovulation testing session but hamstring muscle stiffness (P = .66) did not.
The results indicate that hamstring muscle stiffness did not change across the menstrual cycle and hamstring extensibility increased at ovulation, when estrogen concentration increases.
Jennifer L. Etnier and Benjamin A. Sibley
The purpose of this study was to examine the interactive effects of hormone-replacement therapy (HRT) and physical activity (PA) on the cognitive performance of older women. Postmenopausal women (n = 101) were recruited to complete a PA questionnaire, provide demographic information, and perform the digit-symbol substitution task (DSST) and the trail-making tests (TMT). Regression analyses were conducted for participants with complete data for each cognitive test (DSST n = 62; TMT n = 69). For both tasks, results indicated that PA and education were positively related and age was negatively related to cognitive performance. The interaction of HRT with PA did not add to the predicted variance of either measure of cognitive performance. This was true even after limiting the HRT users to women using unopposed estrogen. It is concluded that the beneficial relationship between PA and these two measures of cognitive performance in postmenopausal women exists irrespective of HRT use.
Steven A. Hawkins, Robert A. Wiswell and E. Todd Schroeder
This study examined the relationships between high-intensity resistance exercise and bone mass in postmenopausal women and serum reproductive-hormone levels and bone-mass changes in response to resistance exercise. Women 45–65 years old were assigned to an exercise or a control group. They trained 3 times weekly for 18 weeks at 90,70, and 80% of their 1-RM. Groups were not different in age, height, body mass, muscle strength, or lean body mass. Initial muscle strength increased significantly in the training group. Total hip and intertrochanter bone-mineral density (BMD) increased in the training group. Estradiol, testosterone, osteocalcin, and CrossLaps concentration did not change in either group. Serum estradiol was significantly related to change in BMD at the hip, femoral neck, and intertrochanter, as well as change in lean mass. Results suggest that high-intensity resistance exercise can increase BMD of the hip and that serum estrogen concentrations might influence bone and muscle adaptations to resistance exercise in postmenopausal women.
Miia Suuriniemi, Harri Suominen, Anitta Mahonen, Markku Alén and Sulin Cheng
This follow-up study confirms our previous findings that the ER-α PvuII polymorphism (Pp) modulates the association between exercise and bone mass. The differences in bone properties of girls with consistently low physical activity (LLPA) and consistently high physical activity (HHPA) were evident only in those bearing the heterozygote ER-α genotype (Pp). In particular, areal bone mineral density of the total femur, bone mineral content and areal bone mineral density of the femoral neck, and bone mineral content and cortical thickness of the tibia shaft were significantly (p < .05) lower in the Pp girls with LLPA than in their HHPA counterparts. These findings might partly explain the genetic basis of human variation associated with exercise training.
Marc Sim, Brian Dawson, Grant Landers, Debbie Trinder and Peter Peeling
The trace element iron plays a number of crucial physiological roles within the body. Despite its importance, iron deficiency remains a common problem among athletes. As an individual’s iron stores become depleted, it can affect their well-being and athletic capacity. Recently, altered iron metabolism in athletes has been attributed to postexercise increases in the iron regulatory hormone hepcidin, which has been reported to be upregulated by exercise-induced increases in the inflammatory cytokine interleukin-6. As such, when hepcidin levels are elevated, iron absorption and recycling may be compromised. To date, however, most studies have explored the acute postexercise hepcidin response, with limited research seeking to minimize/attenuate these increases. This review summarizes the current knowledge regarding the postexercise hepcidin response under a variety of exercise scenarios and highlights potential areas for future research—such as: a) the use of hormones though the female oral contraceptive pill to manipulate the postexercise hepcidin response, b) comparing the use of different exercise modes (e.g., cycling vs. running) on hepcidin regulation.
Ross E. Andersen, Carlos J. Crespo, Shawn C. Franckowiak and Jeremy D. Walston
Hormone-replacement therapy (HRT) and physical activity are both related to aging and health. U.S. minorities are more likely to be inactive and less likely to initiate HRT than are non-Hispanic White women. The purpose of this investigation was to examine the relationship of race and HRT use with physical inactivity among older women (60+ years). The authors used data from 3,479 women who had participated in the Third National Health and Nutrition Examination Survey (NHANES III), conducted in 1988-1994. NHANES III included an in-person interview and a medical examination. The prevalence of physical inactivity among women who reported ever having used HRT was 28.5% (CI 22.9–34.1%), compared with 40.0% (CI 35.9–44.1%) among those who had never used HRT. Mexican American and non-Hispanic Black women reported higher levels of inactivity than did non-Hispanic White women across HRT-use categories. To promote successful aging, physicians should educate postmenopausal women on the possible health benefits of HRT combined with an active lifestyle.
Joshua N. Farr, Deepika R. Laddu and Scott B. Going
Although primarily considered a disorder of the elderly, emerging evidence suggests the antecedents of osteoporosis are established during childhood and adolescence. A complex interplay of genetic, environmental, hormonal and behavioral factors determines skeletal development, and a greater effort is needed to identify the most critical factors that establish peak bone strength. Indeed, knowledge of modifiable factors that determine skeletal development may permit optimization of skeletal health during growth and could potentially offset reductions in bone strength with aging. The peripubertal years represent a unique period when the skeleton is particularly responsive to loading exercises, and there is now overwhelming evidence that exercise can optimize skeletal development. While this is not controversial, the most effective exercise prescription and how much investment in this prescription is needed to significantly impact bone health continues to be debated. Despite considerable progress, these issues are not easy to address, and important questions remain unresolved. This review focuses on the key determinants of skeletal development, whether exercise during childhood and adolescence should be advocated as a safe and effective strategy for optimizing peak bone strength, and whether investment in exercise early in life protects against the development of osteoporosis and fractures later in life.
Matti Hyvärinen, Sarianna Sipilä, Janne Kulmala, Harto Hakonen, Tuija H. Tammelin, Urho M. Kujala, Vuokko Kovanen and Eija K. Laakkonen
including the tests for 6-min walk distance, knee extension force, vertical jump height, and grip strength. In addition, a test–retest reliability analysis was performed. Methods Cohort Description Cross-sectional baseline data of the Estrogenic Regulation of Muscle Apoptosis study were analyzed. The study