RESUMEN
Congenital hypogonadotropic hypogonadism is a rare disorder characterised by impaired testosterone secretion since birth, and represents a valuable model for studying the effects of testosterone replacement therapy (TRT) in humans. This cross-sectional study aimed to investigate all health-related physical fitness (HRPF) components and quality of life in a series of eight men with hypogonadotropic hypogonadism under regular TRT. The study group was compared to a control group of 16 healthy subjects paired for age, body mass index and physical activity. Body composition, aerobic capacity, muscular strength and endurance, and joint flexibility were evaluated in two different 7-day interval time points, based on the pharmacokinetics of testosterone in the hypogonadal group. Quality of life was assessed by the WHOQOL-brief questionnaire. Both groups had similar performances in all HRPF components evaluated, independently of plasma testosterone levels (p > .05). Quality of life was also similar in the four domains analysed (p > .05). The results of this pilot study suggest that regular testosterone replacement was efficient in providing HRPF and quality of life in a series of congenitally hypogonadal men to levels like those observed in healthy men. In addition, acute fluctuations in plasma testosterone did not correlate with changes in muscle strength and endurance.