The yoga program will include breathing exercises, different postures, and meditation. The yoga will be performed in groups. The program will be supervised a physical therapist for two times in a week for eight weeks . A session will be fifty minutes (5-10 minutes: warming-up, 20-25 minutes: postures, 10-15 minutes: cooling down).

Home exercise program will consist of trunk strengthening exercises. The patients will be asked to check the exercise days. Patients will be contacted with telephone once a week.

The children with enthesitis related arthritis will be randomized into one of the exercise groups as yoga or home exercises and will perform the exercise program for 2 times a week for 8 weeks according to their groups.

Six minute walking distance will be used for determining the functional status of lower extremity. The test will be performed in a 15-m corridor. The patient will be asked to walk as fast as possible without running. Standard instructions will be used for motivation. The patients will be allowed to stop if they want without stopping the chronometer. The total distance will be measured at the end of six minutes.

The patients will be asked to climb and descend 13 steps and the time will be recorded.

Pediatric Quality of Life (PedsQL) 3.0 Arthritis Module will be used to assess the quality of life of the patients and their parents.It is a 22-item measure consisting of 5 scales: pain and hurt, daily activities, treatment, worry, and communication. Items are rated on a 5-point Likert scale (0 = Never, 1 = Almost Never, 2 = Sometimes, 3 = Often, 4 = Almost Always). The possible range of scores is 0-88 by summing subscale scores and lower scores indicates better quality of life.