Kushagra, If you are unable to appear for the Physical Education Practical due to health reasons or due to any other unavoidable circumstances, you should contact your Physical Education teacher or the Department Head of your school. Actually, the CBSE practicals are scheduled by the school authorities only in the given schedule released by the CBSE and the Physical Education Teachers do have a good enough understanding with the external Practical evaluator who comes to evaluate your practical. So, it is advised to contact your Physical Education teacher and tell him/her about your condition and ask him for any clarification or way out as these things depend on your teacher and your understanding with him/her.