Flu symptoms after exercising

8.4 (5 reviews) Rate this page

Immune System Expert
Ask a question

19 August 2014

Exercise and the immune system

We hear it all the time: we should exercise more if we want to stay healthy; exercise strengthens our immune system; and it helps us to maintain a healthy weight.

How does it feel, then, when you finish a workout feeling worse than before? Experiencing flu symptoms after exercise is not uncommon, but can be very disconcerting.

Causes of flu symptoms after exercise

There are several reasons why we may experience flu-like symptoms after exercise, including:

Human Growth Hormone – this is a hormone released during exercise to repair muscle and encourage tissue growth. This hormone is vital for proper functioning of our muscles. However, it can make us feel nauseous, and after an intense training session, excess amounts of this hormone are released, making us suffer this symptom.

Dehydration – even if we keep drinking plenty, it is easy to become dehydrated when we exercise, as we lose fluid through sweat and our breath. Dehydration can cause our muscles to feel weak and can result in a headache and dizziness.

Poor nutrition – what you eat feeds your muscles and organs. This means that if you haven’t eaten enough of the right type of food before exercising, then you may struggle to fuel your body during exercise. This can leave you feeling nauseous, fatigued and dizzy.

Flu virus – the flu is caused by the influenza virus, not by exercise. However, a very intense out-of-the-blue bout of exercise may cause your immune system to temporarily weaken, as energy is diverted from it to muscle function. If your symptoms persist and worsen, it may be that you have been hit by a virus

Chronic Fatigue Syndrome or Fibromyalgia– if you experience fatigue and other flu-like symptoms every time after exercise, even if it is only mild, then this may be an indication of a more serious health concern such as Fibromyalgia or Chronic Fatigue Syndrome. Persistent symptoms like this should be checked by a doctor.

Tips to reduce flu symptoms after exercise

Finding the cause of your flu-like symptoms after exercise is the first step towards finding an effective treatment. After a doctor has ruled out any underlying health concerns, often a few simple changes will help to minimise these symptoms.

When you exercise, micro-tears occur in your muscles, and when your body repairs these tears, certain toxic substances are released. These substances can cause aching muscles and other flu like symptoms. Look after your muscles by ensuring you have a proper warm up and warm down when exercising, and if possible try to work in a massage if you are training hard as this will help to reduce micro-tearing and subsequently reduce flu-like symptoms.

Although some people prefer exercising on an empty stomach, remember that doing too much without proper nutrition and hydration can leave you feeling weak. You do not want to eat a huge meal before going for a jog, but allowing a light meal of carbohydrates to settle is often recommended as this gives you slow-release energy. It is also important to eat enough protein for muscle function. Taking a bottle of water with you when exercising (and drinking from it) will help to keep your muscles hydrated throughout your workout.

If you are going to embark on an intense exercise programme, and want to boost your immune system so that you do not pick up bugs, taking a herbal supplement such as Echinacea may help to support your immune system. This herb will also help you to recover more quickly from colds and flu enabling you to get back to exercising as soon as possible.


Echinaforce® Echinacea Drops

For relieving the symptoms of colds and flu. Also in 50ml & 100ml drops.
More info

A.Vogel Echinaforce Hot Drink Cold & Flu Echinacea concentrate for oral solution with Elderberry for the relief of cold and flu symptoms, 100ml


£ 12.99

find your local stockist

Echinaforce® Echinacea Hot Drink. Soothing and palatable hot drink.
More info

What's being asked

Can you catch flu from not washing your hands after going to the toilet?

In general, the answer is no. The bacteria and viruses in the digestive tract and faeces will not ...
Read more >

I think I have the flu, but why does the inside of my nose feel like its burning?

This is all to do with the infection causing inflammation and irritating the mucus lining of the ...
Read more >

I have been feeling really unwell with flu symptoms for over a week now and still not showing any signs of recovery. What would you suggest?

I am sorry to hear that you have been feeling unwell with flu symptoms for the past week. Most ...
Read more >

Is it really the flu?

Our quick quiz helps you figure out if you really do have the flu, or just a nasty cold.

Check your symptoms

Healthy & nutritious dinner ideas

Get new recipes in your inbox every week. Sign up now