Research Question: Does an specific and pre-defined physical exercise prescribed by a specialist provide any benefit on haemophilic arthropathy, the quality of life or the physical condition of patients with haemophilia A and haemophilic arthropathy? Does adherence to physical exercise improve when monitoring patients with an accelerometer? Do compliant patients find higher benefit on haemophilic arthropathy, quality of life or the physical condition than non-compliant patients?