Stabilization exercises help increase strength, stability, balance, gait, and endurance through effective abdominal training. Bridge exercise, which is one of the closed kinetic exercises, is one of the most used spinal stabilization exercises. Although that exercise affects on the trunk muscles, it has been stated that it is related to all muscles of the lower extremity.There are some studies, which are examining the activation of the gluteus maximus, quadriceps, rectus abdominus, iliocostalis lumborum, iliocostalis thoracis, and gastrocnemius muscles while exercising the bridge. Although there are some studies investigating the activation of muscles at different knee angles, there is no study in the literature examining the effect of bridge exercise performed at different knee angles on the strength and endurance of lower extremity and trunk muscles. For these reasons, this study aimed to examine the effect of bridging exercises performed at different knee angles on muscle strength and endurance in healthy subjects.

Participants included in the study will randomly divide into 3 different groups by using simple sealed envelope randomization method. Participants in the first group will perform exercise at knee angle was 45⁰ flexion, the participants in the second group will perform to exercise at knee angle 60⁰ flexion and the participants in the third group will perform exercise knee angle at 90⁰ flexion. All participants will include in a bridging exercise program by a blind researcher at predetermined knee angles (45⁰, 60⁰ 90⁰), 3 sets of 15 repetitions per day, 3 days a week for 6 weeks. Evaluations will be done by a blinded researcher 1 week before starting the 6-week exercise program and 1 week after they finished the program. All evaluations will be made by the same physiotherapist by meeting with participants face to face. Inclusion in the research will be on a voluntary basis. As outcome measures, muscle strength assessment and core Endurance Assessment will be evaluated.

Inclusion Criteria:

• Being between the ages of 18-27
• Not having any health problems diagnosed in terms of starting the exercise program
• Individuals who do not exercise regularly

Exclusion Criteria:

• Having any identified health problem that would prevent the exercise
• Individuals who exercise regularly

There is no plan to make IPD data but when the statistical analysis of all data is made, all results will be shared.