Exercise with Flu or a Cold
Should you exercise when you have a cold or the flu?
Most doctors allow their patients to exercise when they
have a cold, as long as they don't have a fever and their muscles
don't hurt when they exercise. However, it's probably better to
stop exercising altogether when you have an infection. You risk
injury if you exercise when your muscles hurt at rest or when you
start to exercise. When muscles are damaged, they release
enzymes from their cells into the bloodstream and they fill with
blood from broken blood vessels. One study reported markedly
increased muscle damage during relatively minor exercise during
an infection, with blood tests demonstrating increases in muscle
enzymes and ultrasound tests demonstrating hemorrhage into
the muscles.
You also should not exercise when you have a high fever.
When you exercise, your heart has to pump blood to your
muscles to supply them with oxygen. It also has to pump blood
from your muscles to your skin where the heat is dissipated.
When you have a fever, your heart has to work extra hard to get
rid of extra heat. Furthermore, some viruses that infect your nose
and throat can also infect your heart muscle. The combination of
the extra work and an infected heart muscle could cause
irregular heart beats. You won't lose much conditioning unless you take off for more than a week.
Checked 12/29/10