On the other hand, on the other hand, "excessive motor physical activity seems strictly correlated to anything but negligible negative effects, with sometimes serious repercussions on the organism." Perhaps due to a later alignment with the contemporary sports habits of the general population, the female sex is today at the center of numerous studies that analyze the correlations between physical exercise and general health; in particular, the interest of the scientific community seems to be oriented on:
- Impact on life expectancy
- Role in fertility
- Importance in pregnancy
- Properties useful for the symptoms of premenopause
- Prevention of osteoporosis.
In this article we will analyze the positive and negative and positive effects physical exercise can induce on female reproductive function.
For further information: Female Aesthetics and Muscular Hypertrophy and obesity are increasingly common in developed countries, with significant consequences on the health of the general population. The evaluation criterion is the body mass index (BMI), which however should be refined by including the constitution and morphological type, or a measurement of muscle circumferences and subcutaneous fat folds (plicometry); alternatively, bio-impedancemetry can be used.
In sedentary patients who are frankly overweight, in the outpatient setting, to define the extent of this excess and consider the distribution of body fat, it is common practice to evaluate the waist circumference (WC, waist circumference) or the waist to hip ratio (WHR) ) - the latter being less and less used. This is because the android-type adipose distribution is more correlated to metabolic and vascular risks and therefore to death or permanent disability; in women this occurs especially after menopause, when the levels of female sex hormones plummet.
The undeniable unfavorable effects of obesity on health are expressed, in particular, with the increased risk of type 2 diabetes mellitus, hypertension and other metabolic pathologies, therefore atherosclerosis and thrombosis, consequently cardio-cerebro-vascular events, as well as harmful courses on the reproductive system. It has been well demonstrated that weight loss in women is associated with a reduction in the risk of these diseases in obese patients.
In particular, a "high prevalence of obesity in the infertile population was noted, thus demonstrating how body weight plays a fundamental role in the modulation of development and reproductive function. This occurs because excess fat favors an increase in estrogen levels." , following an increase in peripheral conversion - in particular of fat tissue - from androstenedione to oestrone, thus favoring a condition of anovularity, just as occurs in polycystic ovary syndrome (PCOS).
Exercise and increased fertility in the obese
It has recently been shown that obese women subjected to physical exercise for 24 weeks show a reduction in all parameters measuring obesity, and in particular in toilet - the main indicator of insulin resistance - therefore an important reduction in visceral fat; this is demonstrated by the fact that women with reduced WC start to ovulate again. The modification of this parameter therefore not only improves insulin sensitivity, but also plays an important role on muscle, the major site of glucose storage. This effect is expressed because physical exercise increases the expression and activity of proteins involved in the translation of the signal triggered by insulin on skeletal muscle. Moderate physical exercise, through the aforementioned mechanisms, favors an improvement in the regularity of menstrual cycles, therefore, with the resumption of ovulation, an increase in spontaneous fertility is observed. and that obtained with treatment.
The beneficial effect of physical activity is also manifested by an improvement in pregnancy outcomes. In fact, it has been shown that women who have achieved a reduction in body weight following changes in their lifestyle, are less likely to develop complications related to pregnancy, such as gestational diabetes, preeclampsia, and fetal malformations. A reduction in the abortion rate was also noted in these women.
For further information: Workout for Fitness Women metabolic rate that exercise itself induces.Exercise and amenorrhea
These mechanisms occur clinically with the clinical picture of amenorrhea, ie with the absence of spontaneous menstruation for at least 3 months. When this occurs, it is classically referred to as "athletes' amenorrhea". The amenorrhea of athletes can be classified into "primitive amenorrhea", ie when the woman does not present the appearance of the menarche (first menstruation), and secondary, in the event that the menstruation disappears after a more or less long period of spontaneous menstrual flows. "Exercise amenorrhea", together with eating disorder amenorrhea (such as bulimia and anorexia nervosa) is part of functional hypothalamic amenorrhea. The latter must be differentiated from hypothalamic amenorrhea of organic cause, which include those secondary to tumor, ischemic or inflammatory pathology.
The subjects particularly at risk for amenorrhea from excessive physical exercise are above all those who exercise sports such as swimming, fitness, ballet, marathon (...). In these women, amenorrhea is primarily due to a reduction in body weight and a lack of fat mass; these conditions are also aggravated by the reduction in caloric intake by the same subjects.
Neuro-endocrine causes of female amenorrhea
Another important mechanism responsible for the athlete's "amenorrhea" is that of neuro-endocrine stress, with a consequent increase in the inhibitory tone on the hypothalamus by oxytocin, serotonin and melatonin, therefore with reduced secretion of GnRH.
The hormonal picture of athletes' amenorrhea, like those of functional hypothalamic amenorrhea in general, appears to be characterized by a subversion of the normal hypothalamic organization, which induces a deficit of function of the pituitary-ovarian axis. Excessive physical exercise, in fact, is intended from the organism as a condition of stress, which influences the secretion of neuro-endocrine modulators with important alterations on the release of numerous factors, inducing hypogonadotropic hypogonadism.
In particular, there is a reduction in the levels of gonadotropins, an increase in the levels of prolactin, GH, ACTH, glucocorticoids and endorphins; moreover, and especially, there is a state of deep hypoestrogenism, due to poor ovarian function, with important repercussions on bone metabolism. Free androgen levels increased as a result of estrogen deficiency and reduced SHBG levels. TSH, T3 and T4 levels decreased. Furthermore, these subjects have low levels of leptin, a hormone produced by adipose tissue, which is decreased due to the reduction of fat mass. Lastly, the persistence of the stress condition leads to the activation of the hypothalamus-pituitary-adrenal axis and consequent high levels of cortisol.
In women with no menstrual cycle for at least 3 months, as revealed by the accurate medical history conducted by the specialist, it will first be necessary to evaluate the levels of FSH and estradiol, to differentiate between hypogonadotropic and hypergonadotropic hypogonadism; in the case of athletes' amenorrhea there will be one state of hypogonadotropism. To rule out a condition of hypothyroidism or hyperprolactinemia, it will be necessary to proceed with the evaluation of thyroid hormones and prolactin.
Diagnostic process of amenorrhea in athletes
At this point of the diagnostic iter is essential to establish whether it is an amenorrhea related to hypothalamic or pituitary dysfunctions.
GnRH test
For this purpose, the GnRH test will be performed, with single bolus or microinfusion administration.In the case of a single bolus infusion, the GnRH is infused intravenously at a dose of 100 ug, evaluating the response of the gonadotropins by means of blood samples taken 15 minutes apart, for 2 hours. LH levels will rise to maximum values approximately 30 minutes after the start of the test; the levels of FSH will also be elevated, albeit less markedly than those of LH. In the microinfusion GnRH test, on the other hand, GnRH is administered at doses of 0.2-0.4 ug / min for 3 hours intravenously, with evaluation of the gonadotropin response every 15 minutes.
In the event that an absence of LH and FSH response to the test is observed, the hypogonadism will be attributable to a pituitary deficiency, while, in the case of the athletes' amenorrhea, the response to the test will be normal, as it is a hypothalamic pathogenesis. To identify whether hypothalamic amenorrhea is functional, such as that from excessive physical exercise, it will be necessary to exclude, through instrumental tests, possible central organic causes.
Naloxone test
As a final diagnostic step, the naloxone test will be performed. Naloxone is a selective opioid peptide antagonist, and is administered as a single intravenous bolus dose of 2 mg, with LH levels determined every 15 minutes for 2 hours. In women with hypothalamic amenorrhea the administration of naloxone will lead to an increase in LH levels, but not the characteristic peak that, instead, is found in normal subjects.
Therapeutic process of amenorrhea in athletes
The therapeutic approach makes use first of all of the removal of the cause that induced the alteration; it is therefore necessary to advise women to reduce physical activity, together with a recovery of body weight accompanied by a balanced diet. This approach allows, in most cases, to solve the problem.
Given the key role played by endogenous opioids in hypothalamic amenorrhea, oral administration of naloxone is recommended for 3-6 months at a dose of 50 mg / day; usually the results of this approach are good, especially in women who had shown a positive response to the naloxone test during the diagnostic assessment.
Pulsatile GnRH, administered by means of infusion pumps, could be used for therapeutic purposes; in reality, this approach is reserved for women wishing to become pregnant in order to cause the LH peak to induce ovulation. The use of oral contraceptives, on the one hand, has the advantage of favoring the appearance of menstrual-like bleeding in the patient with amenorrhea from excessive physical exercise, on the other hand, it could induce in the patient herself the "erroneous belief that" a cure has taken place, diverting her already scarce attention to her state of health.
For further information: Female Training: Legs and Buttocks --ovary.It is also indisputable that moderate physical activity brings significant health benefits in general and reduces the risk of developing obesity and related diseases, such as cardio-vascular and metabolic alterations.
Furthermore, moderate physical activity is able not only to regulate the menstrual cycle but also to improve a woman's fertility.
For further information: POM Method: Training and Menstrual Cycle
