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.
After a workout, the muscles are sore because the muscle has incurred microscopic tears. Compressing and massaging the muscles helps by pumping and pushing some of the acid out of the muscles. Massage would also benefit you greatly by warming up the muscles and encouraging the healing process.