Stuffy noses, hacking coughs and aches all over -- cold and flu season has arrived. Though your body may be aching and your nose running like a faucet, it can be difficult to decide if you should continue your exercise routine or take a temporary break.

"We all know that exercise is key to good health, but there are times that your body may need a break," said Keith Veselik, MD, director of primary care at Loyola University Health System. "Having to slow down when you're sick is Mother Nature's way of saying don't push it and it's reasonable to pay attention to that."

According to Veselik whether a person should exercise or not can be disease specific. When sick our bodies already are battling against an illness and that takes energy. For instance, adding the extra stress of exercising while sick can be dangerous for a person with a heart condition. A person with diabetes may need to monitor blood glucose levels more often, especially if one is not eating and drinking normally, as being ill may raise glucose levels and exercise may lower them. If you do have a medical condition and are not sure if you should exercise while sick Veselik suggests you call your doctor.

Still, Veselik says a general rule is that it's okay to exercise if your symptoms are above the neck, such as a sore throat or runny nose.

"If you aren't feeling well, but still want to exercise, lower your expectations about what you can do. You don't necessarily need to be in bed all day, but you can't expect to have the same level of energy as you would if you weren't sick," said Veselik.

But, it could be dangerous to exercise if you have the following symptoms:

• Fever

• Shortness of breath or chest congestion

• Body aches

• Diarrhea or Vomiting

• If you feel dizzy or light-headed when you stand up

When making the decision he also suggests thinking about where you will be exercising and who will be exposed to your illness.

"Though sharing is usually a good thing that's not the case when it comes to germs. If you are coughing and sneezing just skip the Zumba class or basketball game and go for a walk or run by yourself instead," said Veselik. "Also, always wipe down machines at the gym. You never who was using it before you."

He also warns to not get your expectations too high when returning to a normal exercise routine.

"People need to pace themselves when getting back into their routine. You won't be able to do as much right away and that's ok. Initially, it should be 50 percent effort and 50 percent duration. Listen to your body and increase according to what it tells you," said Veselik.