To diagnose a problem with the port, try using a different battery and cord for a while. Damaged Power Cord. The power cord is a wire inside a plastic sheath, and the wire can break with or without damage to the sheath. If the power goes on and off as the cord is moved or bent, the wire is likely broken.
You can work out if you're sore. Don't exercise the same muscle groups that are hurting. Do legs one day and exercise your upper body the next. By doing so, you'll still be able to get exercise and allow your lower body to recover and rebuild.
When the muscles are worked, they build up lactic acid and this can cause cramping and sore muscles. For those of you who work out or are athletes, you will need to have more potassium in your system to prevent soreness than a non-athlete.