We all get sick from time to time. Colds, the flu and other illnesses can leave you feeling run down or lacking motivation. But should you stop exercising when you’re ill or will exercise actually help you get better?
According to The Royal College of Physicians, the answer to this question depends on your symptoms and how serious your illness is.
When to avoid exercise
It’s best to avoid exercise if you have any of the following symptoms:
- a fever
- a cough
- a sore chest
- aching muscles or joints
- nausea
- stomach cramps
- diarrhoea
These symptoms can sometimes be signs of an illness that may be made worse by exercising. For example, working out when you have a fever or flu-like symptoms can make you feel worse and raise your body temperature to dangerous levels.
You should avoid exercise if you have an existing heart or lung condition and catch a viral illness.
It’s also best to not workout if minor exercise leaves you feeling breathless, dizzy or lightheaded. Pay attention if you feel dizzy or get chest pain while exercising. These symptoms can be caused by serious medical conditions like heart disease or emphysema.
Exercising with such conditions can be dangerous, so see a doctor to find out if it’s safe for you to exercise.

When it’s safe to exercise with an illness
It’s normally safe to exercise if you have symptoms that are ‘above the neck’. This includes symptoms like:
If you do decide to exercise with a cold, listen to your body. If you feel too tired or sore to keep up with your normal routine, try walking or a low-impact activity like yoga instead.
Although evidence suggests that regular exercise improves your immune system in the long term, intense physical exercise actually weakens your immune system in the short term. This could slow your recovery time and make your symptoms worse, so it’s best to be cautious.

What about long-term or chronic illnesses?
Studies show that careful exercise can help to alleviate the symptoms of some chronic or long-term health conditions, including:
- heart disease
- mental health conditions, such as anxiety and depression
- multiple sclerosis
- diabetes
- cancer
- osteoporosis
- chronic fatigue syndrome
- fibromyalgia
If you have a chronic condition like heart disease, diabetes or osteoporosis you should always talk to a doctor before you start exercising.
They’ll be able to recommend activities that are safe for you. They may also be able to monitor your condition to make sure you’re not putting your health at risk.