This study will be completed in two phases. In the first phase, the participants included in the study will be evaluated first by tele-assessment. One hour later, all assessments will be repeated face-to-face procedures by the researchers; thus, the validity of the tele-assessment method will be determined. Before the tele-assessment, participants will be informed about having a chair whose floor-to-seat height is 48 cm and tape measure. In the second phase of the study, to determine the reliability of the tele-assessment method, all tests will be applied to the previously tested participant by the same researcher one week later and at the same time of the day using only the tele-assessment method.

The Curl-Up test is used to evaluate the trunk flexor muscle strength. In the test, individuals are asked to lie on their back, bring their hips and knees to a 90º flexion position, and perform trunk flexion for 30 seconds. In our study, the result of the Curl-up test will be recorded as the number of repetitions made by individuals for 30 seconds.

Push-up test is used to evaluate general core muscle strength. In the test, individuals are asked to lie in the prone position, bring their hands to shoulder level, their elbows in flexion and to the side of the body, while in this position, they are asked to raise the head, shoulder and trunk with the elbows fully extended for 30 seconds. In our study, the number of repetitions performed by the subjects for 30 seconds will be recorded.

Plank test will be applied to evaluate general core endurance. Participants will be positioned so that their forearms and toes are on the ground and they will be asked to lift their trunk by giving weight. Participants will be informed about the correct alignment of the whole body during the test. The time in which the body's position is maintained will be recorded in seconds and the test will be terminated as soon as the position is broken.

The lateral bridge test is used to test the endurance of the lateral trunk muscles. n the test, the person lying on his back is asked to turn sideways on one side, place his forearm on the ground at an angle of 90º with the arm, and cross his upper arm to the opposite shoulder. The subject is asked to lift his body up on his forearm and toes while in this position and to maintain this position. In our study, with the lateral bridge test, the time that the patients stand without disturbing the movement will be recorded in seconds by means of the stopwatch, the test will be repeated twice for both sides and the best result will be evaluated.