"Give it a try, maybe it will work" or a "trial and error" approach are not options for starting training after muscle injury. This publication demonstrates how critical early and consistent sports medicine care is to the healing process. The history, symptoms, palpation of muscle injuries, functional testing, and identification of the cause are all critical to initiating the right treatment steps at the earliest possible time. Under no circumstances should the control of the increase in load be based on complaints, since the pain already subsides before the healing process is complete. Loading too early correlates with a significantly increased risk of injury.
Update: Muscle Injuries after 45 Years of Professional Sports Care : Diagnosis and Therapy of Neurogenic Muscle Hardening, Muscle Strain, Muscle Fiber Tear and Muscle Bundle Tear