Response to Aerobic Training in Postmenopausal Women With Exercise Intolerance.

Cardiovascular diseases (CVDs) remain the leading cause of morbidity and mortality worldwide and represent a major public health challenge. Importantly, growing evidence highlights significant sex-related differences in the epidemiology, clinical presentation, and pathophysiology of cardiovascular diseases. In particular, postmenopause represents a period of life associated with an increased risk of CVD.

Several physiological mechanisms may underlie these sex-related disparities. Differences in cardiac structure and function, vascular properties, and metabolic regulation contribute to distinct cardiovascular health between men and women. Moreover, the transition to menopause and the associated decline in circulating sex hormones are thought to play a key role in cardiovascular remodeling and functional alterations.

For many years, physical activity has been considered a first-line non-pharmacological strategy in the prevention and treatment of cardiovascular diseases. More specifically, aerobic training has been shown to improves exercise tolerance and quality of life in patients. Indeed, sentinel studies highlight an improvement in aerobic power (VO2 peak) linked to peripheral adaptations (increase in the arteriovenous difference in O2 in the muscles used) and not to central adaptations (no changes in systolic and diastolic functions). However, these studies did not assess the effects of hormonal status , whereas numerous studies on healthy subjects have highlighted the influence of sex hormones on cardiovascular responses to acute and chronic exercise.

The aims of this study:

• Evaluate the effects of 24 aerobic training sessions (over 8-12 weeks) on exercise tolerance in postmenopausal women (peak VO2 and exercise dyspnea using the Borg scale).
• Second, evaluate the effects of 24 aerobic training sessions key indices of cardiovascular physiology (e.g., arterial stiffness, endothelial dysfunction, and muscle oxygenation).
• Thirds, to evaluate the effects of the training sessions on the quality-of-life score of postmenopausal women.

Inclusion criteria

• Postmenopausal women under 70 years of age (absence of menstruation for 12 consecutive months and estradiol < 20 pg/mL and/or FSH > 40 mIU/mL), presenting with unexplained exertional dyspnea.
• COVID-19 vaccination.
• Echocardiographic ejection fraction > 50% and NT-proBNP < 220 pg/mL.
• Women in sinus rhythm or with paroxysmal or permanent atrial fibrillation.
• Women considered physically inactive according to WHO recommendations (150 minutes of moderate-intensity endurance activity per week, or at least 75 minutes of vigorous-intensity endurance activity, or an equivalent combination of moderate- and vigorous-intensity activity.

Exclusion criteria

• Women with significant coronary heart disease, severe valvular disease (grade III or IV/IV), significant hypertrophic or hypertensive heart disease (LVH with wall thickness ≥ 13 mm), infiltrative disease (amyloidosis, Fabry disease, etc.), constrictive disease, or significant and/or progressive arrhythmic disease (ventricular arrhythmia).
• Women with significant obesity (BMI > 30 kg/m²).
• Unstable women (systolic blood pressure < 100 mmHg, resting heart rate > 100 bpm) or women with clinical congestion (cardiac-related lower limb edema, pulmonary crackles).
• Women with pulmonary function tests indicating significant respiratory disease (FEV₁/FVC < 0.7, TLC < LLN).
• Women with chronic renal failure with creatinine clearance < 30 mL/min (MDRD) or on dialysis.
• Women with anemia (Hb < 12 g/dL).
• Women with uncontrolled hypo- or hyperthyroidism (abnormal TSH).
• Women who have undergone left breast augmentation (implant).
• Women under legal guardianship or conservatorship.