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Matthews CE, Fortner RT, Xu X, Hankinson SE, Eliassen AH, Ziegler RG. Association between physical activity and urinary estrogens and estrogen metabolites in premenopausal women. J Clin Endocrinol Metab 2012; 97:3724-33. [PMID: 22855335 PMCID: PMC3674291 DOI: 10.1210/jc.2012-1732] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 06/25/2012] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The objective of the study was to evaluate in premenopausal women the relationships of physically active and sedentary behaviors reported for adulthood and adolescence with a comprehensive profile of estrogen metabolism. METHODOLOGY Fifteen estrogens and estrogen metabolites (jointly termed EM) were measured using liquid chromatography-tandem mass spectrometry in luteal phase urines from 603 premenopausal women in the Nurses' Health Study II. Geometric means of individual EM, metabolic pathway groups, and pathway ratios were examined by level of exposure after adjustment for age, body mass index, alcohol intake, menstrual cycle length, and sample collection timing. RESULTS High overall physical activity in adulthood (42+ metabolic equivalent h/wk vs. <3 metabolic equivalent h/wk) was associated with a 15% lower level of urinary estradiol (Ptrend=0.03) and 15% lower level of 16-hydroxylation pathway EM (Ptrend=0.03). Levels of 2- and 4-hydroxylation pathway EM did not differ significantly by physical activity. High overall activity was also positively associated with four ratios: 2-pathway EM to parent estrogens (Ptrend=0.05), 2-pathway catechols to parent estrogens (Ptrend=0.03), 2-pathway catechols to methylated 2-pathway catechols (Ptrend<0.01), and 2-hydroxyestrone to 16α-hydroxyestrone (Ptrend=0.01). Similar patterns of association were noted for walking and vigorous physical activity, but there was little evidence of associations with sedentary behaviors or activity during adolescence. CONCLUSIONS High levels of physical activity were associated with lower levels of parent estrogens and 16-hydroxylation pathway EM and preferential metabolism to 2-pathway catechols. The results of our analysis, the largest, most comprehensive examination of physical activity and estrogen metabolism to date, may be useful in future studies investigating the etiology of diseases linked to both physical activity and endogenous estrogen.
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Affiliation(s)
- Charles E Matthews
- Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, 6120 Executive Boulevard, Room 3028, Bethesda, Maryland 20892-7246, USA.
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Steiner AZ, Herring AH, Kesner JS, Meadows JW, Stanczyk FZ, Hoberman S, Baird DD. Antimüllerian hormone as a predictor of natural fecundability in women aged 30-42 years. Obstet Gynecol 2012; 117:798-804. [PMID: 21422850 DOI: 10.1097/aog.0b013e3182116bc8] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To generate estimates of the association between markers of ovarian aging and natural fertility in a community sample at risk for ovarian aging. METHODS Women aged 30-44 years with no history of infertility who had been trying to conceive for less than 3 months provided early-follicular phase serum and urine (N=100). Subsequently, these women kept a diary to record menstrual bleeding and intercourse and conducted standardized pregnancy testing for up to 6 months. Serum was analyzed for estradiol, follicle-stimulating hormone (FSH), antimüllerian hormone, and inhibin B. Urine was analyzed for FSH and estrone 3-glucuronide. Diary data on menstrual cycle day and patterns of intercourse were used to calculate day-specific fecundability ratios. RESULTS Sixty-three percent of participants conceived within 6 months. After adjusting for age, 18 women (18%) with serum antimüllerian hormone levels of 0.7 ng/mL or less had significantly reduced fecundability given intercourse on a fertile day compared with women with higher antimüllerian hormone levels (fecundability ratio 0.38; 95% confidence interval [CI] 0.08-0.91). The day-specific fecundability for women with early-follicular phase serum FSH values greater than 10 milli-international units/mL compared with women with lower FSH levels was also reduced, although nonsignificantly (11% of women affected; fecundability ratio 0.44; 95% CI 0.08-1.10). The association with urinary FSH was weaker (27% women affected; fecundability ratio 0.61; 95% CI 0.26-1.26), and the associations for the other markers were weaker still. CONCLUSION Early-follicular phase antimüllerian hormone appears to be associated with natural fertility in the general population. LEVEL OF EVIDENCE II.
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Affiliation(s)
- Anne Z Steiner
- From the Departments of Obstetrics and Gynecology and Biostatistics, University of North Carolina, Chapel Hill, North Carolina; the National Institute for Occupational Safety and Health, Cincinnati, Ohio; the Department of Obstetrics and Gynecology and Preventive Medicine, University of Southern California, Los Angeles, California; and the Epidemiology Branch, National Institute of Environmental Health Science/National Institutes of Health, Research Triangle Park, North Carolina
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Plinta R, Olszanecka-Glinianowicz M, Drosdzol-Cop A, Chudek J, Skrzypulec-Plinta V. The effect of three-month pre-season preparatory period and short-term exercise on plasma leptin, adiponectin, visfatin, and ghrelin levels in young female handball and basketball players. J Endocrinol Invest 2012; 35:595-601. [PMID: 21986458 DOI: 10.3275/8014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE The aim of the study was to assess the effect of a 3-month pre-season preparatory period and shortterm moderate aerobic exercise and intensive fitness and speed exercise on adipokine and ghrelin levels in young female handball and basketball players. MATERIALS AND METHODS Fifty healthy young female professional basketball and handball players were enrolled into the study before the opening of the season (after a 2-month holiday with no training or dietary restrictions). Serum estradiol and plasma leptin, adiponectin, visfatin, and ghrelin levels were determined at the beginning and the end of a 3-month period of moderate aerobic training. Plasma adipokines and ghrelin levels were additionally assessed after 2 h of moderate aerobic exercise or after intensive fitness and speed exercise training. RESULTS Long-term moderate aerobic exercise was followed by a significant decrease in plasma ghrelin and leptin levels (921±300 vs 575±572 pg/ml, p<0.001 and 16.4±15.6 vs 11.8±16.3 ng/ml, p<0.01, respectively); plasma adiponectin and visfatin remained unchanged. No changes were observed in plasma ghrelin and leptin levels after short-term moderate aerobic exercise or after intensive fitness and speed exercise. Plasma visfatin concentration increased significantly after short-term moderate aerobic exercise (22.1±8.7 vs 27.6±9.0 ng/ml, p<0.001), whilst adiponectin increased after intensive fitness and speed exercise (16.7±7.8 vs 21.0±9.8 μg/ml, p<0.001). CONCLUSIONS Regular moderate aerobic training in preparation for the match season is followed by a decline in circulating leptin and ghrelin levels even in athletes without body weight changes. Short-term intensive fitness and moderate aerobic exercise seem to modulate the production of different adipokines.
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Affiliation(s)
- R Plinta
- Department of Physical Education and Sport, Medical University of Silesia, ul. Medyków 12, Katowice, Poland
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A prospective cohort study of physical activity and time to pregnancy. Fertil Steril 2012; 97:1136-42.e1-4. [PMID: 22425198 DOI: 10.1016/j.fertnstert.2012.02.025] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 02/16/2012] [Accepted: 02/16/2012] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To investigate the association between leisure-time physical activity (PA) and fecundability. DESIGN Prospective cohort study. SETTING Internet-based observational study of Danish women who were planning a pregnancy (2007-2009). PATIENT(S) A total of 3,628 women aged 18-40 years at baseline. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Time to pregnancy (TTP). Fecundability ratios (FRs) and 95% confidence intervals (CIs) were derived from discrete-time Cox models, with adjustment for potential confounders, such as body mass index (BMI). RESULT(S) We observed an inverse monotonic association between vigorous PA and fecundability (≥ 5 h/wk vs. none: FR 0.68, 95% CI 0.54-0.85) and a weak positive association between moderate PA and fecundability (≥ 5 vs. <1 h/wk: FR 1.18, 95% CI 0.98-1.43) after mutual adjustment for both PA types. Inverse associations between high vigorous PA and fecundability were observed within subgroups of age, parity status, and cycle regularity, but not among overweight or obese women (BMI ≥ 25 kg/m(2)). CONCLUSION(S) There was evidence for a dose-response relationship between increasing vigorous PA and delayed TTP in all subgroups of women with the exception of overweight and obese women. Moderate PA was associated with a small increase in fecundability regardless of BMI. These findings indicate that PA of any type might improve fertility among overweight and obese women, a subgroup at higher risk of infertility. Lean women who substitute vigorous PA with moderate PA may also improve their fertility.
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Kossman DA, Williams NI, Domchek SM, Kurzer MS, Stopfer JE, Schmitz KH. Exercise lowers estrogen and progesterone levels in premenopausal women at high risk of breast cancer. J Appl Physiol (1985) 2011; 111:1687-93. [PMID: 21903887 DOI: 10.1152/japplphysiol.00319.2011] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Experimental and clinical data support a role for estrogens in the development and growth of breast cancer, and lowered estrogen exposure reduces breast cancer recurrence and new diagnoses in high-risk women. There is varied evidence that increased physical activity is associated with breast cancer risk reduction in both pre- and postmenopausal women, perhaps via lowered estrogen levels. The purpose of this study was to assess whether exercise intervention in premenopausal women at increased breast cancer risk reduces estrogen or progesterone levels. Seven healthy premenopausal women at high risk for breast cancer completed a seven-menstrual-cycle study. The study began with two preintervention cycles of baseline measurement of hormone levels via daily first-morning urine collection, allowing calculation of average area under the curve (AUC) hormone exposure across the menstrual cycle. Participants then began five cycles of exercise training to a maintenance level of 300 min per week at 80-85% of maximal aerobic capacity. During the last two exercise cycles, urinary estradiol and progesterone levels were again measured daily. Total estrogen exposure declined by 18.9% and total progesterone exposure by 23.7%. The declines were mostly due to decreased luteal phase levels, although menstrual cycle and luteal phase lengths were unchanged. The study demonstrated the feasibility of daily urine samples and AUC measurement to assess hormone exposure in experimental studies of the impact of interventions on ovarian hormones. The results suggest value in exercise interventions to reduce hormone levels in high-risk women with few side effects and the potential for incremental benefits to surgical or pharmacologic interventions.
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Affiliation(s)
- D A Kossman
- National Analysts Worldwide, Philadelphia, PA, USA
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Montgomery MM, Shultz SJ. Isometric knee-extension and knee-flexion torque production during early follicular and postovulatory phases in recreationally active women. J Athl Train 2011; 45:586-93. [PMID: 21062182 DOI: 10.4085/1062-6050-45.6.586] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CONTEXT Acute decreases in strength have been associated with risky biomechanical strategies that might predispose one to injury. Whether acute changes in thigh muscle torque occur across the menstrual cycle remains equivocal. OBJECTIVE We compared maximal voluntary isometric contraction (MVIC) torque of the knee flexors and extensors between the early follicular (EF) and either the early luteal (EL) or midluteal (ML) phases, which were confirmed by serum hormone concentrations. We expected that MVIC torques would increase from the EF to the EL phase after estradiol peaked and before increased exposure to progesterone. DESIGN Cohort study. SETTING Applied Neuromechanics Research Laboratory. PATIENTS OR OTHER PARTICIPANTS Seventy-one recreationally active women (age range, 18-30 years). INTERVENTION(S) The MVICs were measured 1 day during menses and 1 day during the 8 days after ovulation. Participants were grouped by the hormone profile of their luteal test days as EL phase, ML phase, or anovulatory cycle. MAIN OUTCOME MEASURE(S) The MVIC torque of knee flexors and extensors (Nm/kg), estradiol (pg/mL), progesterone (ng/mL), and testosterone (ng/dL). RESULTS We tested 29 women during their EL phases, 32 during their ML phases, and 10 during anovulatory cycles. Although we observed relatively large individual changes in sex hormone concentrations and MVIC torques across the 2 test sessions, we observed no difference in MVIC torque between test phases (F(1,68) = 1.17, P = .28) or among groups by test phase (F(2,68) = 0.31, P = .74). CONCLUSIONS Thigh MVIC torque did not change from time of menses (when estradiol and progesterone were lowest) to time in the luteal phase after an unopposed estradiol rise or combined estradiol and progesterone rise. However, these findings were limited to MVIC torque production measured at 2 different times, and further research examining these relationships at multiple times and using other measures of neuromuscular function is needed.
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Affiliation(s)
- Melissa M Montgomery
- Department of Kinesiology, Applied Neuromechanics Research Laboratory, University of North Carolina at Greensboro, NC 27402-6170, USA.
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Mumford SL, Schisterman EF, Siega-Riz AM, Gaskins AJ, Steiner AZ, Daniels JL, Olshan AF, Hediger ML, Hovey K, Wactawski-Wende J, Trevisan M, Bloom MS. Cholesterol, endocrine and metabolic disturbances in sporadic anovulatory women with regular menstruation. Hum Reprod 2010; 26:423-30. [PMID: 21115506 DOI: 10.1093/humrep/deq322] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Sporadic anovulation among regularly menstruating women is not well understood. It is hypothesized that cholesterol abnormalities may lead to hormone imbalances and incident anovulation. The objective was to evaluate the association between lipoprotein cholesterol levels and endocrine and metabolic disturbances and incident anovulation among ovulatory and anovulatory women reporting regular menstruation. METHODS The BioCycle Study was a prospective cohort study conducted at the University at Buffalo from September 2005 to 2007, which followed 259 self-reported regularly menstruating women aged 18-44 years, for one or two complete menstrual cycles. Sporadic anovulation was assessed across two menstrual cycles. RESULTS Mean total and low-density lipoprotein cholesterol and triglycerides levels across the menstrual cycles were higher during anovulatory cycles (mean difference: 4.6 (P = 0.01), 3.0 (P = 0.06) and 6.4 (P = 0.0002) mg/dl, respectively, adjusted for age and BMI). When multiple total cholesterol (TC) measures prior to expected ovulation were considered, we observed a slight increased risk of anovulation associated with increased levels of TC (odds ratio per 5 mg/dl increase, 1.07; 95% confidence interval, 0.99, 1.16). Sporadic anovulation was associated with an increased LH:FSH ratio (P = 0.002), current acne (P = 0.02) and decreased sex hormone-binding globulin levels (P = 0.005). CONCLUSIONS These results do not support a strong association between lipoprotein cholesterol levels and sporadic anovulation. However, sporadic anovulation among regularly menstruating women is associated with endocrine disturbances which are typically observed in women with polycystic ovary syndrome.
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Affiliation(s)
- Sunni L Mumford
- Epidemiology Branch, Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, DHHS, 6100 Executive Boulevard 7B03, Rockville, MD 20852, USA
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Epperson CN, Toll B, Wu R, Amin Z, Czarkowski KA, Jatlow P, Mazure CM, O’Malley SS. Exploring the impact of gender and reproductive status on outcomes in a randomized clinical trial of naltrexone augmentation of nicotine patch. Drug Alcohol Depend 2010; 112:1-8. [PMID: 20561758 PMCID: PMC2946976 DOI: 10.1016/j.drugalcdep.2010.04.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 04/14/2010] [Accepted: 04/15/2010] [Indexed: 10/19/2022]
Abstract
In a series of exploratory analyses, we examined the roles of gender, reproductive status and negative affect on smoking abstinence in subjects participating in a large (n=385) 6-week randomized clinical trial (RCT) of nicotine patch therapy, with varying doses of oral naltrexone (0mg, 25mg, 50mg, 100mg) treatment. Negative affect was assessed daily during the first post-quit week via telephone interactive voice response (IVR). Weight and adverse events were recorded weekly. In the intent to treat sample, the effects of dose on continuous abstinence were non-significant in the overall model for men and women. In the 295 study completers, there was a significant effect of dose on continuous abstinence in women only (F=8.53, p=0.04). In the 100mg group, 71% of women were continuously abstinent compared to 41% in the placebo group (p<0.05). Women in the active naltrexone groups gained less weight (F=2.91, df=3, p=0.04). Women in the 100mg vs. placebo group were less adherent with medication (F=3.19, p<0.05). These effects were not significant in men. Naltrexone treatment condition (100mg vs. placebo, p=0.02, odds ratio (OR)=0.28), gender (OR=0.55 p=0.09), and IVR ratings of negative affect (OR 1.02, p=0.04) predicted abstinence at Week 1 in study completers. Menstrual cycle status on quit day had a modest affect on abstinence. These data suggest that naltrexone dose, gender, and negative affect play a role in smoking abstinence, particularly in the early stages of treatment. When used in conjunction with nicotine replacement therapy, naltrexone dose may be important in women.
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Affiliation(s)
- C. Neill Epperson
- University of Pennsylvania School of Medicine Department of Psychiatry, Philadelphia, PA 19104 USA,University of Pennsylvania School of Medicine Department of Obstetrics and Gynecology; Philadelphia, PA 19104 USA
| | - Benjamin Toll
- Yale University School of Medicine Department of Psychiatry, New Haven, CT 06520 USA
| | - Ran Wu
- Yale University School of Medicine Department of Psychiatry, New Haven, CT 06520 USA
| | - Zenab Amin
- Yale University School of Medicine Department of Psychiatry, New Haven, CT 06520 USA
| | - Kathryn A. Czarkowski
- University of Pennsylvania School of Medicine Department of Psychiatry, Philadelphia, PA 19104 USA
| | - Peter Jatlow
- Yale University School of Medicine Department of Laboratory Medicine; New Haven, CT 06520 USA
| | - Carolyn M. Mazure
- Yale University School of Medicine Department of Psychiatry, New Haven, CT 06520 USA,Yale University, Department of Psychology, New Haven, CT 06520 USA,Yale University, Women’s Health Research at Yale; New Haven, CT 06520 USA
| | - Stephanie S. O’Malley
- Yale University School of Medicine Department of Psychiatry, New Haven, CT 06520 USA,Yale University, Department of Psychology, New Haven, CT 06520 USA
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Williams NI, Reed JL, Leidy HJ, Legro RS, De Souza MJ. Estrogen and progesterone exposure is reduced in response to energy deficiency in women aged 25-40 years. Hum Reprod 2010; 25:2328-39. [PMID: 20605898 DOI: 10.1093/humrep/deq172] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Alterations in circulating steroids are believed to be important mediators of the impact that diet and exercise have on breast cancer risk and changes in bone density. This study aimed to test the hypothesis that moderate exercise training combined with caloric restriction would produce significant menstrual disturbances and alterations in ovarian steroids in premenopausal women. METHODS Sedentary premenopausal women (25-40 years; body mass index: 23.6 +/- 0.6 kg/m(2)) assigned to either a light conditioning (LC, n = 9) or an exercise combined with caloric restriction group (EX + CR, n = 24) were studied for one screening, one baseline and four intervention periods equivalent to the length of subjects' menstrual cycles. Exercise consisted of supervised training sessions, i.e. two LC or four EX + CR times per week, 30-60 min at a moderate intensity. The EX + CR group was prescribed a diet representing a caloric restriction of 20-35% below baseline energy requirements, whereas the LC group remained eucaloric. Ovarian steroid exposure was determined with daily urinary estrone-1- and pregnanediol glucuronides (E1G and PdG, respectively) and mid-cycle urinary LH measures. Fitness, body composition, and serum sex hormone binding globulin (SHBG) and serum estradiol (E2) were assessed repeatedly. RESULTS The intervention produced significant increases in VO(2) max and decreases in both body weight (-3.7 +/- 0.5 kg; ranged from -8.8 to +1.8 kg) and percent body fat (-4.5 +/- 0.7%; ranged from -12 to +0.3%), which were attributable primarily to changes in the EX + CR subjects (time x group; P < 0.05). Serum E2 and urinary E1G and PdG concentrations declined significantly across the intervention period (time; P < 0.05), whereas SHBG increased transiently (time; P < 0.05) in the EX + CR subjects, with no significant changes observed in the LC group. The decrease in E1G area under the curve was significantly related to the daily energy deficit (R =0.61; P = 0.003), not the amount of weight lost. There was no significant impact of the intervention on menstrual cyclicity or the incidence of menstrual disturbances in either group. CONCLUSIONS A moderate aerobic exercise training program combined with modest weight loss in accordance with recommended guidelines produces significant reductions in ovarian steroid exposure without disrupting menstrual cyclicity in premenopausal women aged 25-40 years. Exposure to a daily energy deficit is a stronger predictor of the decline in estrogen exposure than decreases in body weight.
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Affiliation(s)
- N I Williams
- Department of Kinesiology, Women's Health and Exercise Laboratories, Penn State University, Noll Laboratory, University Park, PA 16802, USA.
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Abstract
OBJECTIVE To determine the prevalence of the female athlete triad (low energy availability, menstrual dysfunction, and low bone mineral density) in high school varsity athletes in a variety of sports compared with sedentary students/control subjects. DESIGN Prospective study. SETTING Academic medical center in the Midwest. PARTICIPANTS Eighty varsity athletes and 80 sedentary students/control subjects volunteered for this study. INTERVENTION Subjects completed questionnaires, had their blood drawn, and underwent bone mineral density testing. MAIN OUTCOME MEASURES Each participant completed screening questionnaires assessing eating behavior, menstrual status, and physical activity. Each subject completed a 3-day food diary. Serum hormonal, thyroid-stimulating hormone, and prolactin levels were determined. Bone mineral density and body composition were measured by dual-energy x-ray absorptiometry. RESULTS Low energy availability was present in similar numbers of athletes (36%) and sedentary/control subjects (39%; P = 0.74). Athletes had more menstrual abnormalities (54%) compared with sedentary students/control subjects (21%) (P < 0.001). Dual-energy x-ray absorptiometry revealed that 16% of the athletes and 30% of the sedentary/control subjects had low bone mineral density (P = 0.03). Risk factors for reduced bone mineral density include sedentary control student, low body mass index, and increased caffeine consumption. CONCLUSIONS A substantial number of high school athletes (78%) and a surprising number of sedentary students (65%) have 1 or more components of the triad. Given the high prevalence of triad characteristics in both groups, education in the formative elementary school years has the potential to prevent several of the components in both groups, therefore improving health and averting long-term complications.
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Direct innervation of GnRH neurons by metabolic- and sexual odorant-sensing leptin receptor neurons in the hypothalamic ventral premammillary nucleus. J Neurosci 2009; 29:3138-47. [PMID: 19279251 DOI: 10.1523/jneurosci.0155-09.2009] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Leptin acts via its receptor (LepRb) on specific CNS neurons to signal the adequacy of long-term energy stores, thereby permitting the expenditure of resources on energy-intensive processes such as reproduction. The ventral premammillary nucleus of the hypothalamus (PMv), which has been implicated in the stimulation of gonadotropin release by olfactory cues, contains numerous LepRb neurons, suggesting a potential role for LepRb PMv neurons in transmitting both metabolic and odorant signals to the neuroendocrine reproductive system. Indeed, Fos immunoreactivity and electrophysiologic recordings revealed the direct activation of LepRb PMv neurons by leptin, and exposure to odors from mice of the opposite sex promoted Fos immunoreactivity (Fos-IR) in many LepRb PMv neurons. To determine the regions innervated by the LepRb PMv neurons, we used two novel cre-activated tract-tracing systems in Lepr(cre) animals; data from these systems and from standard tracing techniques revealed that LepRb PMv neurons project to a subset of the regions, including the preoptic area, that are innervated by the PMv as a whole. Furthermore, the retrograde accumulation in LepRb PMv neurons of a trans-synaptic tracer from GnRH neurons revealed the direct innervation of GnRH neurons by many LepRb PMv neurons. Thus, LepRb PMv neurons sense metabolic and sexual odorant cues and project to the rostral hypothalamus to directly innervate GnRH neurons. These results are consistent with a role for LepRb PMv neurons in regulating the reproductive axis in response to metabolic and odorant stimuli.
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Dietary and lifestyle predictors of age at natural menopause and reproductive span in the Shanghai Women's Health Study. Menopause 2009; 15:924-33. [PMID: 18600186 DOI: 10.1097/gme.0b013e3181786adc] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Modifiable factors predicting the onset of menopause, a transition with important implications for women's health, have not been fully characterized. We evaluated the impact of dietary, lifestyle and reproductive factors on age at natural menopause and reproductive span in Chinese women. DESIGN Study participants were Chinese women aged 40 to 70 who experienced natural menopause and participated in a population-based, prospective study, the Shanghai Women's Health Study (N = 33,054). Dietary intake at the baseline survey was assessed by food-frequency questionnaire. Regression (beta) coefficients, calculated by multivariable linear regression, were used to estimate the effects of dietary, lifestyle, and reproductive patterns on age at menopause and the number of reproductive years, adjusting for potential confounding factors. RESULTS Early menarche, younger age at first live birth, older age at last live birth, longer duration of breast-feeding, and higher parity were associated with longer reproductive years (Ptrend < 0.01 for all). Higher body mass index at age 20, mid-life weight gain, and leisure-time physical activity during adolescence and adulthood predicted later menopause and longer reproductive span (Ptrend < 0.01 for all). Total intake of calories, fruits, and protein was positively associated with later menopause (Ptrend < 0.05 for all) and longer reproductive span (Ptrend < 0.05), except for carbohydrates (Ptre(nd) = 0.06), and long-term tea consumption predicted longer reproductive span (Ptrend = 0.03). Vegetable, fat, soy, and fiber intakes did not significantly affect reproductive span or age at menopause. Smoking was inversely associated with both early age at menopause and shorter reproductive span (Ptrend < 0.01). CONCLUSIONS In addition to reproductive factors, intake of fruits and protein, smoking, tea consumption, lifetime patterns of physical activity, and weight gain influenced the onset of menopause and/or reproductive span in Chinese women.
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Bethea CL, Centeno ML, Cameron JL. Neurobiology of stress-induced reproductive dysfunction in female macaques. Mol Neurobiol 2008; 38:199-230. [PMID: 18931961 PMCID: PMC3266127 DOI: 10.1007/s12035-008-8042-z] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Accepted: 09/15/2008] [Indexed: 11/24/2022]
Abstract
It is now well accepted that stress can precipitate mental and physical illness. However, it is becoming clear that given the same stress, some individuals are very vulnerable and will succumb to illness while others are more resilient and cope effectively, rather than becoming ill. This difference between individuals is called stress sensitivity. Stress sensitivity of an individual appears to be influenced by genetically inherited factors, early life (even prenatal) stress, and by the presence or absence of factors that provide protection from stress. In comparison to other stress-related diseases, the concept of sensitivity versus resilience to stress-induced reproductive dysfunction has received relatively little attention. The studies presented herein were undertaken to begin to identify stable characteristics and the neural underpinnings of individuals with sensitivity to stress-induced reproductive dysfunction. Female cynomolgus macaques with normal menstrual cycles either stop ovulating (stress sensitive) or to continue to ovulate (stress resilient) upon exposure to a combined metabolic and psychosocial stress. However, even in the absence of stress, the stress-sensitive animals have lower secretion of the ovarian steroids, estrogen and progesterone, have higher heart rates, have lower serotonin function, have fewer serotonin neurons and lower expression of pivotal serotonin-related genes, have lower expression of 5HT2A and 2C genes in the hypothalamus, have higher gene expression of GAD67 and CRH in the hypothalamus, and have reduced gonadotropin-releasing hormone transport to the anterior pituitary. Altogether, the results suggest that the neurobiology of reproductive circuits in stress-sensitive individuals is compromised. We speculate that with the application of stress, the dysfunction of these neural systems becomes exacerbated and reproductive function ceases.
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Affiliation(s)
- Cynthia L Bethea
- Division of Reproductive Sciences, Oregon National Primate Research Center, Beaverton, OR 97006, USA.
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Abstract
During periods of metabolic stress, animals must channel energy toward survival and away from processes such as reproduction. The reproductive axis, therefore, has the capacity to respond to changing levels of metabolic cues. The cellular and molecular mechanisms that link energy balance and reproduction, as well as the brain sites mediating this function, are still not well understood. This review focuses on the best characterized of the adiposity signals: leptin and insulin. We examine their reproductive role acting on the classic metabolic pathways of the arcuate nucleus, NPY/AgRP and POMC/CART neurons, and the newly identified kisspeptin network. In addition, other hypothalamic nuclei that may play a role in linking metabolic state and reproductive function are discussed. The nature of the interplay between these elements of the metabolic and reproductive systems presents a fascinating puzzle, whose pieces are just beginning to fall into place.
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Affiliation(s)
- Jennifer W Hill
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
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65
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Altered autonomic nervous system activity as a potential etiological factor of premenstrual syndrome and premenstrual dysphoric disorder. Biopsychosoc Med 2007; 1:24. [PMID: 18096034 PMCID: PMC2253548 DOI: 10.1186/1751-0759-1-24] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Accepted: 12/20/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Premenstrual syndrome (PMS) encompasses a wide variety of cyclic and recurrent physical, emotional, and behavioral symptoms occurring during the late luteal phase of the menstrual cycle and abating shortly following the beginning of menses. Although PMS is widely recognized, its etiopathogenesis is not yet understood. The present study investigates whether the activity of the autonomic nervous system, which plays a vital role in orchestrating physiological homeostasis within the human body, is altered during the menstrual cycle of women with different degrees of premenstrual symptomatology. METHODS Sixty-two women in their 20s to 40s with regular menstrual cycles participated in this study. All subjects were examined during the follicular and late luteal phases. Cycle phase was determined by the onset of menstruation and oral temperature and was verified by concentrations of ovarian hormones, estrone, and pregnanediol in a urine sample taken early in the morning. Autonomic nervous system activity was assessed by means of heart-rate variability (HRV) power spectral analysis during supine rest. The Menstrual Distress Questionnaire was used to evaluate physical, emotional, and behavioral symptoms accompanying the menstrual cycle of the subjects. The subjects were categorized in three groups, Control, PMS, and premenstrual dysphoric disorder (PMDD) groups, depending on the severity of premenstrual symptomatology. RESULTS No intramenstrual cycle difference in any of the parameters of HRV was found in the Control group, which had no or a small increase in premenstrual symptoms. In contrast, Total power and high frequency power, which reflect overall autonomic and parasympathetic nerve activity, respectively, significantly decreased in the late luteal phase from the follicular phase in the PMS group. As for the PMDD group, which had more severe symptoms premenstrually, heart-rate fluctuation as well as all components of the power spectrum of HRV were markedly decreased regardless of the menstrual cycle compared to those of the other two groups. CONCLUSION Several theories have been proposed to explain the underlying mechanisms of PMS with its complex web of bio-psycho-social factors. Although causes and consequences continue to elude, the present study provides intriguing and novel findings that the altered functioning of the autonomic nervous system in the late luteal phase could be associated with diverse psychosomatic and behavioral symptoms appearing premenstrually. In addition, when symptoms become more severe (as seen in women with PMDD), the sympathovagal function might be more depressed regardless of the menstrual cycle.
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Matsumoto T, Ushiroyama T, Tatsumi N. Lower peripheral circulation in eumenorrheic young women with premenstrual symptoms. Biopsychosoc Med 2007; 1:8. [PMID: 17391537 PMCID: PMC1851706 DOI: 10.1186/1751-0759-1-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Accepted: 03/29/2007] [Indexed: 11/29/2022] Open
Abstract
Background A majority of women from all cultures and socioeconomic levels experience diverse psychosomatic and behavioral symptoms premenstrually, a phenomenon commonly termed premenstrual syndrome, although symptoms and discomfort levels vary from woman to woman. The underlying pathological mechanisms of premenstrual syndrome remain unknown; however, altered function or even slight disorder of the blood circulation system, which contributes to the orchestrations of the human internal environment, could cause bio-psychological changes leading to complaints and ultimately compromising a woman's overall health. The present study, therefore, investigates to what extent and how the menstrual cyclicity of peripheral circulation is associated with premenstrual symptomatology. Methods Twenty-one eumenorrheic young women participated in this study. All subjects were investigated during the follicular and late luteal phases. Cycle phase was determined by the onset of menstruation and oral temperature and was verified by concentrations of ovarian hormones, estrone, and pregnanediol in a urine sample taken early in the morning. Peripheral circulation was evaluated with the Astrim (Sysmex, Kobe), a portable non-invasive monitoring device using the principle of near-infrared spectroscopy, which calculates the venous oxygenation index (VOI) based on the ratio of light absorption of oxyhemoglobin and deoxyhemoglobin, a proven reliable indicator of peripheral blood circulation. The Menstrual Distress Questionnaire was applied to measure physical, emotional, and behavioral symptoms accompanying the menstrual cycle of the subjects. Results The oral temperature and urinary ovarian hormones adjusted for creatinine significantly increased in the late luteal phase in all subjects. While 10 subjects experienced no symptoms during the menstrual cycle, 11 subjects had apparent physical and psychological discomfort in the late luteal phase. We found that VOI decreased more significantly in the late luteal phase than in the follicular phase only in women with premenstrual discomfort although the symptoms were not unbearable enough to cause the disruption of daily activities. Conclusion Several models have tried to explain the etiopathogenesis of premenstrual syndrome. Although causes and consequences remain enigmatic, our data suggest that the peripheral circulation could alter in the luteal phase, which might be partly associated with premenstrual psychosomatic symptoms in eumenorrheic young women.
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Affiliation(s)
- Tamaki Matsumoto
- Department of Health Science, International Buddhist University, 3-2-1 Gakuenmae, Habikino, Osaka, 583-8501, Japan
| | | | - Noriyuki Tatsumi
- Department of Health Science, International Buddhist University, 3-2-1 Gakuenmae, Habikino, Osaka, 583-8501, Japan
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De Souza MJ, Alleyne J, Vescovi JD, Williams NI, VanHeest JL, Warren MP. Correction of misinterpretations and misrepresentations of the female athlete triad. Br J Sports Med 2007; 41:58-9. [PMID: 17185528 PMCID: PMC2465140 DOI: 10.1136/bjsm.2006.031070] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Stoddard JL, Dent CW, Shames L, Bernstein L. Exercise training effects on premenstrual distress and ovarian steroid hormones. Eur J Appl Physiol 2006; 99:27-37. [PMID: 17039366 DOI: 10.1007/s00421-006-0313-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/14/2006] [Indexed: 10/24/2022]
Abstract
Preliminary studies suggest that moderate physical activity may reduce both premenstrual distress (PD) and the ovarian steroid hormones, progesterone and estradiol, which have been implicated in PD. We attempted to replicate these findings, while exploring possible relationships between hormone levels and PD. In a cross-sectional study, 20 moderate exercisers and 34 sedentary women completed PD symptom questionnaires and collected urine samples, daily, throughout a complete menstrual cycle. PD was calculated as the difference in symptom scores reported during the average of the 4 days prior to menses and the average of the 4 days closest to mid-cycle. Urine samples taken from the last quarter of the menstrual cycle were analyzed for urinary estrone glucoronide (E1G) and pregnanediol glucoronide. In a prospective study the same measures were used with 14 sedentary women before and after a 24-week moderate exercise-training program. In the cross-sectional study, exercising women reported lower Pain symptoms, and had lower peak E1G levels than did sedentary women. The baseline PD symptoms loneliness, crying, and skin blemishes with were statistically significantly and positively correlated with pregnanediol glucoronide levels in the cross-sectional study. In the prospective study, exercise reduced the global PD symptom score, including the Water Retention and Pain scales, and reduced pregnanediol glucoronide and peak E1G levels. Moderate aerobic exercise may lessen both PD symptoms and late luteal phase ovarian hormone levels. An exercise program may benefit women with progesterone-related premenstrual affect disturbance.
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Affiliation(s)
- Jacqueline L Stoddard
- Division of Cancer Control and Population Sciences, National Cancer Institute, Behavioral Research Program, Tobacco Control Research Branch, 20892-7337 Bethesda, MD, USA.
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Affiliation(s)
- L DiPietro
- The John B Pierce Laboratory, Yale University, New Haven, CT 06511, USA.
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71
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Abstract
The various menstrual disorders in athletes may reflect different degrees of exposure to a disrupting factor or differences in the susceptibility of various women to disruption. The incidences of these disorders are not well documented, but they appear to be highest in aesthetic, endurance and weight-class sports, and at younger ages, higher training volumes and lower bodyweights. The morbid effects of these disorders include infertility, low bone mass, impaired endothelium-dependent vasodilation, and impaired skeletal muscle oxidative metabolism. The high incidences of menstrual disorders in athletes may derive in part from the self-selection of extraneously affected women into athletics, but many women acquire their menstrual disorders in athletics by failing to adequately increase dietary energy intake in compensation for exercise energy expenditure. Applied research is needed to develop effective dietary interventions that are acceptable to athletes.
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Participation in leanness sports but not training volume is associated with menstrual dysfunction: a national survey of 1276 elite athletes and controls. Br J Sports Med 2005; 39:141-7. [PMID: 15728691 DOI: 10.1136/bjsm.2003.011338] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To examine the prevalence of menstrual dysfunction in the total population of Norwegian elite female athletes and national representative controls in the same age group. METHODS A detailed questionnaire that included questions on training and/or physical activity patterns, menstrual, dietary, and weight history, oral contraceptive use, and eating disorder inventory subtests was administered to all elite female athletes representing the country at the junior or senior level (aged 13-39 years, n = 938) and national representative controls in the same age group (n = 900). After exclusion, a total of 669 athletes (88.3%) and 607 controls (70.2%) completed the questionnaire satisfactorily. RESULTS Age at menarche was significantly (p<0.001) later in athletes (13.4 (1.4) years) than in controls (13.0 (1.3) years), and differed among sport groups. A higher percentage of athletes (7.3%) than controls (2.0%) reported a history of primary amenorrhoea (p<0.001). A similar percentage of athletes (16.5%) and controls (15.2%) reported present menstrual dysfunction, but a higher percentage of athletes competing in leanness sports reported present menstrual dysfunction (24.8%) than athletes competing in non-leanness sports (13.1%) (p<0.01) and controls (p<0.05). CONCLUSIONS These novel data include virtually all eligible elite athletes, and thus substantially extend previous studies. Age at menarche occurred later and the prevalence of primary amenorrhoea was higher in elite athletes than in controls. A higher percentage of athletes competing in sports that emphasise thinness and/or a specific weight reported present menstrual dysfunction than athletes competing in sports focusing less on such factors and controls. On the basis of a comparison with a previous study, the prevalence of menstrual dysfunction was lower in 2003 than in 1993.
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Abstract
Exercise-induced or athletic menstrual dysfunction (amenorrhoea, oligomenorrhoea, anovulation, luteal phase deficiency, delayed menarche) is more common in active women and can significantly affect health and sport performance. Although athletic amenorrhoea represents the most extreme form of menstrual dysfunction, other forms can also result in suppressed estrogen levels and affect bone health and fertility. A number of factors, such as energy balance, exercise intensity and training practices, bodyweight and composition, disordered eating behaviours, and physical and emotional stress levels, may contribute to the development of athletic menstrual dysfunction. There also appears to be a high degree of individual variation with respect to the susceptibility of the reproductive axis to exercise and diet-related stresses. The dietary issues of the female athlete with athletic menstrual dysfunction are similar to those of her eumenorrhoeic counterpart. The most common nutrition issues in active women are poor energy intake and/or poor food selection, which can lead to poor intakes of protein, carbohydrate and essential fatty acids. The most common micronutrients to be low are the bone-building nutrients, especially calcium, the B vitamins, iron and zinc. If energy drain is the primary contributing factor to athletic menstrual dysfunction, improved energy balance will improve overall nutritional status and may reverse the menstrual dysfunction, thus returning the athlete to normal reproductive function. Because bone health can be compromised in female athletes with menstrual dysfunction, intakes of bone-building nutrients are especially important. Iron and zinc are typically low in the diets of female athletes if meat products are avoided. Adequate intake of the B vitamins is also important to ensure adequate energy production and the building and repair of muscle tissue. This review briefly discusses the various factors that may affect athletic menstrual dysfunction and two of the proposed mechanisms: the energy-drain and exercise-intensity hypotheses. Because energy drain can be a primary contributor to athletic menstrual dysfunction, recommendations for energy and the macro- and micronutrients are reviewed. Methods for helping the female athlete to reverse athletic menstrual dysfunction are discussed. The health consequences of trying to restrict energy intake too dramatically while training are also reviewed, as is the importance of screening athletes for disordered eating. Vitamins and minerals of greatest concern for the female athlete are addressed and recommendations for intake are given.
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Affiliation(s)
- Melinda M Manore
- Department of Nutrition and Food Management, Oregon State University, Corvallis, Oregon 97331, USA.
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Matthews CE, Shu XO, Jin F, Dai Q, Hebert JR, Ruan ZX, Gao YT, Zheng W. Lifetime physical activity and breast cancer risk in the Shanghai Breast Cancer Study. Br J Cancer 2001; 84:994-1001. [PMID: 11286483 PMCID: PMC2363839 DOI: 10.1054/bjoc.2000.1671] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Overall physical activity in adolescence and adulthood, and changes in activity over the lifespan were analysed by in-person interviews among 1459 women newly diagnosed with breast cancer and 1556 age-matched controls in urban Shanghai. Physical activity from exercise and sports, household, and transportation (walking and cycling) was assessed in adolescence (13-19 y) and adulthood (last 10 y), as was lifetime occupational activity. Logistic regression was used to estimate odds ratios (OR) and 95% confidence limits (OR (95% CL)) while controlling for confounders. Risk was reduced for exercise only in adolescence (OR = 0.84 (0.70-1.00)); exercise only in adulthood (OR = 0.68 (0.53-0.88)), and was further reduced for exercise in both adolescence and adulthood (OR = 0.47 (0.36-0.62)). Graded reductions in risk were noted with increasing years of exercise participation (OR(1-5 yrs)= 0.81 (0.67-0.94); OR(6-10 yrs)= 0.74 (0.59-0.93); OR(11-15 yrs)= 0.55 (0.38-0.79); OR(16 + yrs)= 0.40 (0.27-0.60);P(trend,)< 0.01). Lifetime occupational activity also was inversely related to risk (P(trend)< 0.01). These findings demonstrate that consistently high activity levels throughout life reduce breast cancer risk. Furthermore, they suggest that women may reduce their risk by increasing their activity levels in adulthood.
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Affiliation(s)
- C E Matthews
- Department of Epidemiology and Biostatistics, University of South Carolina School of Public Health and the South Carolina Cancer Center, Columbia, SC 29208, USA
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Janse de Jonge XA, Boot CR, Thom JM, Ruell PA, Thompson MW. The influence of menstrual cycle phase on skeletal muscle contractile characteristics in humans. J Physiol 2001; 530:161-6. [PMID: 11136868 PMCID: PMC2278395 DOI: 10.1111/j.1469-7793.2001.0161m.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The influence of the different phases of the menstrual cycle on skeletal muscle contractile characteristics was studied in 19 regularly menstruating women. Muscle function was measured when (i) oestrogen and progesterone concentrations were low (menstruation), (ii) oestrogen was elevated and progesterone was low (late follicular phase), and (iii) oestrogen and progesterone were both elevated (luteal phase).Maximal isometric quadriceps strength, fatiguability and electrically stimulated contractile properties were measured. Isokinetic knee flexion and extension strength and fatiguability were also assessed as well as handgrip strength. Menstrual cycle phases were confirmed through measurement of oestrogen, progesterone, follicle stimulating hormone and luteinising hormone. No significant changes were found in any of the muscle function parameters throughout the menstrual cycle (n = 15). The muscle function measurements showed no significant correlations with any of the female reproductive hormone concentrations. These results suggest that the fluctuations in female reproductive hormone concentrations throughout the menstrual cycle do not affect muscle contractile characteristics.
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Affiliation(s)
- X A Janse de Jonge
- School of Exercise and Sport Science, Faculty of Health Sciences, The University of Sydney, East Street, Lidcombe, Australia.
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