Background: With the growth of running popularity, the number of running-related injuries has risen. Longterm training and inadequate training loads are only a few factors causing overload injuries amongst runners. Aim of the study: To determine factors influencing the onset of pain and injury in runners. Material and methods: The study involved 150 runners aged 17-64 years (mean age: 30 ± 10 years) and was conducted via a questionnaire containing questions concerning, for example, training frequency, location of pain, type of trauma, treatment and rehabilitation. Results: 38% (n = 57) of runners often felt pain during training. 41% of them (n = 23) reported pain after running short distances and it was most frequently located in the knee joints (26%, n = 15). 48% (n = 72) experienced a running injury. The largest percentage of these (36%, n = 26) were related to knee injuries. As factors causing injuries, the interviewees mentioned one-sided training plan (24%, n = 17), overtraining (24%, n = 17), and insufficient warm-up (16%, n = 12). The analysis of the results has shown a statistically relevant positive correlation (r = 0.177, p < 0.05) between weekly frequency of training and the number of injuries sustained in the last year. The higher the weekly frequency, the more often injures occur amongst runners. Conclusions: The study shows that the occurrence of pain and injury depends on many factors. A frequent cause of any disturbances within the musculoskeletal system is overloaded soft tissue caused by overtraining. Lower limbs, particularly knee joints, are mostly at risk.