After the marathon, your immune status will be depressed. Because of the physiological hit to the immune system created by the stress of running a marathon, colds, flu, and other upper respiratory tract infections are potential problems in the days and weeks that follow. The best medicine is prevention. After the marathon, take care to allow yourself more sleep than before the race. Resume a well-balanced, nutritious diet immediately following the race. During the first week following the race, focus on rehydration.
Consider using herbal preparations, such as Echinacea (but only after reviewing product information).
If you do develop a cold, flu, or upper respiratory tract infection, remember that sleep, diet, and hydration remain important self-care weapons. Remember: if you have a fever, do not run. Also, if you must take medications (whether over-the-counter or prescription) for your illness, don’t run. Seek professional care if you develop a persistent fever or cough. Consider herbal remedies for their therapeutic benefit.
Easy running can be resumed when there is no fever, no medications are required, and there’s no residual fatigue or malaise. You should not resume hard running until there’s no residual respiratory tract congestion (usually 2 to 3 weeks after easy running can be resumed).