Aim of this project is to delineate sustainable physical exercise programs and to assess the effects of such programs mainly on endocrine-metabolic and neurovegetative outcomes in a cohort of men with metabolic syndrome-related late-onset central hypogonadism.

Participants will undergo a personalised exercise program. After 6 months they will be subdivided into two groups, according to the weekly physical activity volume actually performed (above or below 600 MET·minutes/week). Changes in endocrine-metabolic and neurovegetative outcomes will be compared between the two groups.

Inclusion Criteria:

• diagnosis of late-onset central hypogonadism: total T levels < 8 nmol/L (or < 12 nmol/L in the presence of calculated free T < 225 pmol/L) combined with sexual symptoms (erectile dysfunction, low libido and loss of waking erections) [12];
• diagnosis of metabolic syndrome, defined as association of waist circumference (WC) > 94 cm and at least two among the following criteria: triglycerides ≥ 150 mg/dl, HDL-C < 40 mg/dl, glucose > 100 mg/dl, blood pressure (BP) ≥ 130/85 mmHg [33];
• ability to give informed consent, in accordance with good clinical practice rules and applicable national laws.

Exclusion Criteria:

• History of hypothalamus-pituitary organic disorders and/or testicular diseases;
• impossibility to assess cardiac autonomic regulation due to arrhythmias and/or current treatment for heart rate (HR) control (e.g., beta-blockers, antiarrhythmics);
• impossibility to undergo clinical assessment;
• impossibility or contraindications to perform exercise program (for instance, psychiatric disorders, severe musculoskeletal diseases, arrhythmias);
• inability to give informed consent or unwillingness to be enrolled in the study.