A muscle strain occurs when muscle fibers are stretched or torn, often due to overexertion or improper use. This injury can happen during physical activities, such as sports or heavy lifting, and is commonly felt in areas like the back, legs, or arms. Symptoms typically include pain, swelling, and limited movement in the affected area. Treatment for a muscle strain usually involves rest, ice, compression, and elevation, often referred to as the RICE method. In more severe cases, physical therapy may be recommended to help restore strength and flexibility. Most strains heal within a few weeks with proper care.