By Michaela Ryan

Is it okay to keep exercising when you have a cold? What about the flu? With winter bugs going around, it's important to know how to alter your training if you do cop a germ or two.

Above the neck

"The guidelines are pretty easy," says Dr Lorenzo Masci from the Alphington Sports Medicine Clinic. "Anything above the neck — so if you've got a cold for example, a runny nose or a sore throat — then you should probably cut down your exercise by half and do 50 percent of what you normally do."

Below the neck

"If you've got anything below the neck, like muscle pain, joint pain or fever, you shouldn't really exercise at all until those general symptoms settle down," Lorenzo says. He points out that a cough would also fall into this more serious category.

"For example, if anyone comes in with a fever and a runny nose, I'd tell them to stop exercising until the fever and the muscle ache settles. Then they can start their training again at 50 percent once all those symptoms settle, even if they've got a bit of a runny nose or a sore throat."

"The reason we tell people to stop exercising is because if you exercise when you're unwell it can make the illness worse and prolong it."

There is a second reason Lorenzo advises his patients to stop exercising when they have "below the neck" symptoms. In the event you have an illness which affects your heart, exercise can sometimes actually lead to death.

"People should really see a doctor if they've got aches and pains and fever," Lorenzo advises.

Prevention

Lorenzo advises his patients to take zinc and vitamin C as a way of preventing colds and flus. But he concedes that this is controversial — some studies have shown that these supplements can improve immune function while other studies have cast doubt on the issue.

The good news is that if you exercise regularly, you're likely to improve your immune function.

"If you exercise too much, it can predispose you to coughs and sniffles," he points out. This is often the case for elite athletes who train every day, such as triathletes.

"But what we do know is that if you exercise at a moderate level, your immune system improves such that you're probably at a lower risk of developing coughs and colds."

So don't let these cold winter mornings put you off your exercise routine! It's probably the time of year we most need to keep our immune systems in tip top condition.

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