Endocrine "conditioning" with endurance training a preliminary review

Mid-Cycle Pain in Endometriosis: Clinical Correlations and Potential Etiological Factors

Rojas HE et al., 2026 · Journal of women's health (2002)

To characterize differences between individuals with and without mid-cycle pain in a registry cohort with endometriosis. Prospective analysis of data from the Endometriosis Pelvic Pain Interdisciplinary Cohort Data Registry (Clinicaltrials.gov #NCT02911090) at a tertiary referral center in Western Canada. Three hundred forty-five individuals aged 18-49 years who: (1) had at least one episode of menstrual bleeding in the last 3 months, (2) attended a baseline initial visit, and (3) subsequently had surgery with histological confirmation of endometriosis between January 2018 and December 2023. Exclusion criteria included (1) previous hysterectomy; (2) hormonal suppressive therapy use in the last 3 months; and (3) missing data on mid-cycle pain, history of hormonal therapy use, or menstrual cycle regularity. N/A. Mid-cycle pain in the last month versus No mid-cycle pain in the last month. Of the 345 participants, 67% (n = 232) reported mid-cycle pain in the last month. Mid-cycle pain in the last month was significantly associated with higher mean Central Sensitization Inventory score (48 ± 17 versus 36 ± 16, p < 0.001) and more months of prior hormonal suppressive therapy use (58 [14-120] versus 26 [0-109], p = 0.012). Abnormal anatomy at the time of surgery (e.g., endometrioma, ovarian adhesions) was not associated with mid-cycle pain in the last month. In this endometriosis cohort at a tertiary referral center, most participants reported mid-cycle pain in the last month, which was associated with central sensitization but was not clearly related to endometriosis anatomical distortion.

"The pill" suppresses adolescent bone growth, no matter the estrogen dose

Brajic TS et al., 2021 · CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne

No adverse effects of medroxyprogesterone treatment without estrogen in postmenopausal women: double-blind, placebo-controlled, crossover trial

Prior JC et al., 1994 · Obstet Gynecol

To determine whether cyclic medroxyprogesterone treatment given without estrogen causes adverse symptoms in postmenopausal women. This was a placebo-controlled, double-blind, crossover trial of 10 days/month of medroxyprogesterone and placebo treatments given during 2 consecutive months in random order. Participants recorded their physiologic and emotional experiences on a 0-4 scale using a daily diary form. Eleven postmenopausal women aged 43-63 completed the study. The subjects were not taking hormones. Height, weight, and serum estradiol concentration were measured once. In each woman, the sum of scores for the 10 days of medroxyprogesterone was compared to the sum of scores for the 10 days of placebo using nonparametric tests. No significant differences in scores were found between the 10 days on medroxyprogesterone and the 10 days on placebo. The median and range for the composite scores for premenstrual-like symptoms were 26 (20-67) during medroxyprogesterone and 25 (19-40) during placebo (P = .39). Medroxyprogesterone given alone does not cause adverse symptoms in postmenopausal women. Therefore, medroxyprogesterone therapy, by itself, cannot explain the side effects reported by postmenopausal women taking combined hormones.

Conditioning exercise decreases premenstrual symptoms: a prospective, controlled 6-month trial

Prior JC et al., 1987 · Fertil Steril

Six months of exercise training was associated with decreased premenstrual symptoms in two groups of women. There was no change in symptoms in nontraining women. Eight sedentary (ST) women increased running from 0 to 76 +/- 26 km/cycle (mean +/- standard deviation) over 6 months and seven runners (MT) trained for a marathon (42.2 km). Six normally active, nontraining (C-NT) women kept their activity constant. Each subject completed monthly intensity-graded questionnaires or kept daily symptoms diaries concerning premenstrual symptoms. All monitored basal body temperature, weight, and exercise. Gonadal steroids were measured in ST women. For ST subjects, breast (P = 0.005), fluid (P = 0.01), and personal stress (P = 0.025) decreased. MT women experienced decreased fluid (P = 0.034) and depression (P = 0.014). Anxiety tended to decrease (P = 0.087). ST and MT subjects experienced decreases in premenstrual symptoms without documented hormonal, menstrual cycle, or weight changes. These symptom changes appear to be the earliest evidence of the effects of conditioning exercise on the reproductive system.

The effect of physical activity across the menstrual cycle on reproductive function

Ahrens KA et al., 2014 · Ann Epidemiol

To evaluate the association between physical activity (PA) across the menstrual cycle and reproductive function. The BioCycle Study (2005-2007) followed 259 healthy premenopausal women not using hormonal contraceptives for up to two menstrual cycles (N = 509 cycles). Serum leptin, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and testosterone were measured five to eight times per cycle. Linear mixed models were used to estimate the effect of past-week PA (measured four times during each cycle) on hormone levels. Past-week PA was categorized into tertiles based on metabolic equivalent of task hours per week (cut-points were 15.3 and 35.7). Risk ratios for sporadic anovulation were estimated using generalized linear models. Analyses adjusted for habitual PA (assessed at baseline), body mass index, race, age, and perceived stress. Linear mixed models used inverse probability weights to control for concurrent reproductive hormones and caloric intake. High past-week PA was inversely associated with leptin (-6.6%; 95% confidence interval, -10.6 to -2.5) and luteal phase progesterone (-22.1%; -36.2 to -4.7) as compared with low past-week PA. High past-week PA was not significantly associated with sporadic anovulation (adjusted risk ratio, 1.5; 0.6 to 3.4). High levels of PA were modestly associated with changes in select hormones but not sporadic anovulation among moderate to highly active premenopausal women.

Conditioning exercise and premenstrual symptoms

Prior JC et al., 1987 · J Reprod Med

Exercise is commonly listed as a remedy for the premenstrual syndrome (PMS), although no study has proven that it is an effective therapy. Numerous reports have suggested that exercise is associated with improved mood and symptoms. In those reports, however, the diagnosis of PMS was not clearly documented, nor was the exercise carefully controlled. Preliminary evidence suggests that exercise training in ovulatory, sedentary women and intensified training in women athletes decrease mild premenstrual symptoms. Although conditioning exercise is associated with short luteal phase and anovulatory cycles, decreases in mild premenstrual symptoms occur prior to menstrual cycle changes. Controlled studies of PMS and exercise training may not only document an effective, nonpharmacologic therapy for PMS but also clarify the hormonal etiology of this complex biobehavioral phenomenon.

Physical exercise and the neuroendocrine control of reproduction

Prior JC, 1987 · Baillieres Clin Endocrinol Metab

Reproductive change during conditioning exercise (physical training provides a model of hypothalamic adaptation to alterations in the external and internal environment. Parallels exist between the reproductive changes with exercise and those occurring with physical illness, undernutrition and psychological trauma. Although menstrual cyclicity may be disrupted in younger women, luteal phase shortening, anovulation and decreased premenstrual symptoms within normal ovulatory cycles are the most frequent observations noted. Baseline LH, prolactin and oestradiol tend to be lower, and other hormones unchanged, in trained women. Testosterone may be decreased within the normal range in men. Recent evidence shows that LH pulse frequency, amplitude and area under the LH curve are decreased in both female and male runners. Interrelationships between increases in central dopamine, endorphin and probably some hypothalamic message(s) relating to nutritional state appear to modulate these reproductive changes. The clinical and therapeutic response to reproductive alterations in the context of exercise differs when these are seen as adaptive and not as disease processes (Prior and Vigna, 1985b).