Should you exercise when you have a cold or flu? - HR Future helps people prepare for the Future of Work and is South Africa's leading print, digital and online Human Resources magazine.

Should you exercise when you have a cold or flu?

In winter we spend more time indoors which means we are in closer contact with other people who may be carrying germs.
But flu is not something to be sneezed at and worldwide up to five million people get seriously ill during the ‘flu season’ and around a quarter of a million die from it, so it makes sense to take the necessary precautions to stay well this season.  

You may not be able to banish those lurgies completely but research shows that moderate levels of regular exercise are thought to help increase the immune system. Studies indicate that if you exercise regularly as opposed to leading a sedentary lifestyle, you are not immune but less prone to illnesses ‘This does not mean you should exercise when you have flu though.

Be warned though that this doesn’t mean the harder you exercise the better off you are! In fact, often overdoing it or a really hard workout can knock your immune, system especially in the first 24 hours.

Ever had inexplicable sniffles or a sore throat the day after what you would consider a ‘good workout’? These symptoms of what’s medically known as an upper respiratory tract illness or infection (URTI). This is more likely to happen after continuous, prolonged (more than 1.5 hours) of moderate to high-intensity exercise. This is even more prevalent if you are not eating the correct foods.
So, the trick is moderate exercise and good nutrition and your body should be able to fight off the bugs on its own. When you consider that we experience about two to four common cold episodes a year and sore throats are the most common reason for athletes visiting the doctor, it makes sense to coddle yourself in winter – not only to keep away colds and sore throats but to prevent them becoming bad enough to need antibiotics.
The main cause of respiratory infections are viruses such as rhinovirus and adenovirus that result in symptoms of the common cold and flu viruses that cause the more severe symptoms of flu. It is recommended that those who have poor immune systems or are over the age of 65 should have a flu injection before the start of winter, although you can be inoculated right up until the end of August.

If you are unlucky enough to catch one of these lurgies, there are some basic guidelines for safe exercising during your illness and recovery.

Should infection occur, exercisers must use some basic guidelines for exercise during infectious episodes. It is a good idea though to get the go ahead from your doctor before you begin exercising:

• DAY 1 of illness: Do not exercise strenuously when experiencing URTI symptoms like a sore throat, coughing, runny or congested nose. Avoid ALL exercise when experiencing symptoms like muscle/joint pain and headache, fever and generalised feeling of malaise, diarrhoea or vomiting.
• DAY 2: Avoid exercise if fever, diarrhoea or vomiting present or if coughing is increased. If no fever is present and there is no worsening of ‘above the collar’ symptoms; undertake light exercise (heart rate < 120 beats per minute) for 30-45 minutes (indoors during winter), by yourself.
• DAY 3: If fever and URTI (or gastrointestinal) symptoms are still present, consult your doctor. If no fever is present and there is no worsening of initial symptoms; undertake moderate exercise (heart rate < 150 beats per minute) for 45-60 minutes, preferably indoors and by yourself.
• DAY 4: If there is no symptom relief, do not try to exercise and visit your doctor. If this is the first day of improved condition, wait one day without fever and with improvement of URTI or gastrointestinal symptoms before returning to exercise.
• Finally, it is important to stop training and consult your doctor if a new episode with fever occurs or if initial symptoms become worse, coughing persists or breathing problems during exercise occur.

It is generally agreed that prevention is always preferable to treatment and here are some some practical guidelines to keeping healthy during winter:

• Advise ‘sick’ co-workers to stay at home if symptoms are infectious – or avoid them at work if they do come in;
• Wash hands regularly, before meals and after direct contact with potentially contagious people, animals, blood, secretions, public places and bathrooms;
• Use disposable paper towels and limit hand to mouth/nose contact when suffering from respiratory or gastrointestinal infection symptoms. Carry alcohol-based hand-washing gel with you;
• Do not share drinking bottles, cups, towels, etc with other people. Ensure adequate dietary energy, protein and essential micronutrient intake and avoid crash dieting and rapid weight loss. It is a good time to take a nutritional supplement including Vitamin C;
• Ensure adequate carbohydrate intake before and during strenuous prolonged exercise;
• Wear appropriate outdoor clothing in inclement weather and avoid getting cold and wet after exercise (have a change of dry clothes);
• Get adequate sleep (at least 7 hours per night is recommended); and
• Keep other life stresses to a minimum where possible.
Of course it’s best to avoid getting ill at all by maintaining a healthy lifestyle, getting enough exercise and taking precautions which are reasonable and practical. But if you are ill, remember to look after your body and give yourself time to recover before you step on life’s and the gym’s treadmill again!

Sourced by Bonitas Medical Fund.


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