This is a question that has yet to produce a definitive answer. It is well established that the ability to compete athletically is reduced during an illness. In addition, exercising when sick can lead to a severe debilitating state known as 'Post-viral Fatigue Syndrome.' Symptoms of this condition include weakness, inability to train hard, easy fatigability, frequent infections, and depression.
The American College of Sports Medicine (ACSM) has made the following recommendations for exercising during and illness.
If one has common cold symptoms (runny nose and/or sore throat without a fever), intense exercise training may be safely resumed a few days after the resolution in symptoms.
Mild to moderate-intensity exercise (e.g. walking) when sick with a common cold does not appear to be harmful.
With symptoms of fever, extreme tiredness, muscle aches, and swollen lymph glands, 2 to 4 weeks should probably be allowed before resumption of intense training.
Leonel Muralles, Disease Management Coordinator for the East Jefferson General Hospital Wellness Center, can be reached at 504-889-7203.