Research confirms the effectiveness of training based on specific sports discipline in the therapy of people with intellectual disabilities. The aim of the study was to determine the influence of climbing activities on the physical fitness of people with ID. This is a randomised, controlled trial. In total, 68 people with diagnosed mild or moderate intellectual disabilities took part in the study. An experimental group participated in the activities on an artificial climbing wall for a period of 15 weeks. The assessment of physical fitness included selected samples from the Eurofit and Eurofit Special tests set. Statistical analysis was carried out with Statistica 13 programme. After the end of the programme, the balance measured by a walk on a bench and the strength of upper limbs assessed by bent arm hang test, push a 2 kg medicine ball and dynamometric measurement of handgrip force were significantly improved in the experimental group. The index of the relative strength of both limbs, depending on body weight, also increased. Participation in climbing activities has a positive effect on the level of some components of the physical fitness of people with ID and maybe an alternative form of therapy.