Tight hip flexors can cause pain and performance issues. The hip flexors are a group of muscles that include the iliopsoas, as well as the rectus femoris. They work to bring the legs and trunk together, which helps you complete your ab exercises, lift your knees and bring your thighs

Marcus runs the site Strengthery where he writes about weight training, weight loss, and other health-related topics. After injuring both his shoulders and realizing that his posture sucked, he became obsessed with learning everything he could about how to improve and maintain good posture and now likes to share what he