Hip strains occur when one of the muscles (gluteals, adductor muscles, or iliopsoas muscles) and tendons supporting the hip joint become stretched or torn. These strains can be a simple stretch in the muscles or tendons, or they may be a partial or complete tear of the muscle fibers or combination of muscles and tendons. Hip strains can be mild, moderate, or severe depending on the extent of the injury, and can occur at any time. Signs and symptoms of a hip strain may include pain and tenderness in the injured area, increased pain when using the muscle, swelling, limited range of motion, and muscle weakness. Mild strains improve with rest, ice, compression, and elevation of the affected hip, and NSAIDs, such as ibuprofen to help reduce swelling and relieve pain.
Frequently, hip strains happen suddenly from stretching, a fall, a direct blow during contact sports, and overuse when muscles and tendons have slowly weakened over time by negative movements like squatting, dead lifts, and lunges. Once a muscle is injured, it can be reinjured. Repeated strains in the muscles surrounding the hip and pelvis are called an athletic pubalgia (sports hernia), a strain or tear of any soft tissue (tendons, ligaments in the lower abdomen or groin area). The likelihood of increasing the risk for muscle strains can occur if you have had a prior injury to the same area, are experiencing muscle tightness, fail to warm up properly before exercising, attempt to do too much too quickly when you begin to exercise, and over exhaust the muscle. Severe strains can limit your ability to move your hip. If you have a severe hip strain, please contact your primary care physician or general practitioner. Severe strains may require physical therapy or other medical treatment.

References
American Academy of Orthopedic Surgeons. (2020). Hip Strains.
https://orthoinfo.aaos.org/en/diseases–conditions/hip-strains#:~:text=%20Home%20Remedies%20%20
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SciePro. (2020). [Illustration]. 3d rendered medically accurate illustration of a woman having a painful hip. https://www.shutterstock.com/image-illustration/3d-rendered-medically-accurate-illustration-woman-1613953615.