A push-up isn’t a newbie exercise and it’s more challenging than most people think. It requires strength, body control and stability. Those are 3 common mistakes: Butt in the hair/hip sagging: there should be a natural curvature of the spine. You need to activate your core, hip flexors and quads to maintain a great position; Spreading out your elbows, instead of keep them aligned to your body: try to keep a 45/degree - 10/degree arm angle; Feet positioning is so important: