Muscle strains occur mainly during exercise. Patients experience sudden onset of significant pain during exercise, localised pain and swelling after the injury, and discomfort may be triggered by re-exercising to contract the muscle in that area. Intermittent claudication, on the other hand, usually has no obvious trigger and has a slower onset, with severe pain and discomfort or a feeling of heaviness in the limb after a certain distance each time during ordinary walking, and which is relieved after a few moments of rest. A distinction can thus be made.