Easing into your side plank gradually before fully loading it with your body weight will help avoid joint and/or muscle strain. This is done with warmups and modifications. Warm up your obliques with small curl-ups that go to the side. To begin, lie on the floor with knees bent and feet flat. Perform a few straight-on curl-ups to get going.

For beginners, a modified side plank or knee side plank is a great starting point, gradually progressing to more advanced forms like the weighted side plank or side plank with hip abduction for increased resistance and benefit.

Start in a traditional side plank position. Raise your top arm straight above you. Then lower your arm and rotate your core as you thread your top arm through the space under you. Stop when your shoulders are close to being parallel to the floor. Unthread your arm and return to the starting position.