Exercise helps to keep us in good health. Doctors at the American Heart Association suggest getting at least 150 minutes of proper physical activity every week. Many people exercise for a few minutes every day or every other day. So, getting 150 minutes every week is easy.But what about those times when you are sick? If you do not feel well, should you keep following your exercise habit? Health experts answer these and other questions.Edward R. Laskowski is a doctor at the Mayo Clinic. He and other experts have a general rule of yes about exercising when you are sick. It is usually fine to exercise, he explains, if your symptoms (症状)are all “above the neck". These signs may include a runny nose, a blocked nose, sneezing or a minor sore throat.Geralyn Coopersmith is a physical fitness trainer who has written several books on exercise and nutrition. Both Coopersmith and Dr. Laskowski suggest taking a break from exercising if signs of your illness appear "below the neck". Pay special attention to symptoms such as chest congestion, extreme cough or pain in the stomach.There are other symptoms that can tell you to avoid exercise. They include: a higher than normal body temperature, a sense of feeling extremely tired, and widespread muscle pain.Both Coopersmith and Dr. Laskowski suggest listening to your body. If you feel really bad, take a break and let your body rest. If you don't feel too bad, these experts both suggest reducing the amount of exercise. For example, if you usually run, take a quick walk instead.