Can It Prevent the Flu?
Maybe. The best way to stay well is to keep your immune system strong. When you exercise, your white blood cells -- the ones that fight infections -- travel through your body faster and do their jobs better.
There are other benefits to being more active, like less stress and better sleep. Stress is bad for your body and mind. You can ease it with regular exercise. Get 7 to 8 hours sleep a night, too, because that also helps keep your body's defenses in good shape.
On the other hand, too much exercise -- like spending hours at the gym or running marathons -- can bring your immune system down. Extreme workouts can slash the number of white blood cells you have and boost the level of stress hormones in your bloodstream.
Can I Work Out if I Have the Flu?
Try to take it easy. Rest gives your body a chance to recover. Your immune system works best when it isn’t in overdrive.
If you have a fever, skip the workout. People usually run one for 2 to 5 days when they have the flu. It means your body is battling the infection. A high temperature pulls moisture out of your body. So does a workout. If you get too dried out, it could delay your recovery.
Also, the flu is contagious. You can spread it to others for up to 7 days after your symptoms start. If you work out around other people, wait until your fever breaks and stays down on its own for at least 24 hours before you go back to your routine.
If you don't have a fever yet but you do have other flu symptoms, talk to your doctor before you head to the gym.