A Muscle strain is a common injury caused by the stretching or tearing of muscle or its surrounding tendons. Muscle spasm is defined as an uncontrolled, spontaneous muscle contraction that can feel like a cramp and send a sudden pop of pain through your body.
For muscle strains, you may notice pain when in a resting state, swelling, redness, weakness, lack of mobility, weakness, and soreness. For muscle spasms, you will notice a burst of pain throughout your body at random times.
In order to restore movement in your body and strengthen weakened muscles to take pressure off the parts of your body prone to cramping, and make the muscles more mobile as well.