Exercise: friend or foe to the immune system?

Today, Builder is brought to you by another popular topic. As we all know, the most effective ways to protect yourself from the corona virus are social distancing (including staying at home) and maintaining good hygiene. If you keep a distance of 1.5 to 2 m from other people and don't touch your face with dirty hands, you've already followed the two biggest measures to avoid infection.

However, there are also a few secondary measures that are strongly recommended in the war against the virus.

Recently we learned that wearing a mask does not provide full protection, but can be useful in certain situations. We also know that the protection of the immune system should not be neglected during these times, since the immune system protects the human body from viruses, bacteria and other harmful external factors.

Both preventing and overcoming diseases or infections goes more smoothly if your immune system is strong as an ox. You can read more about strengthening your immune system through nutrition and supplements here. We also mentioned in that article that you should not stop working out, regardless of the lockdown. Now, let me explain it in more detail.

Let's talk science: how does exercise impact your immune system?

Exercise revs up circulation. As a result, the immune cells are also constantly on the move, and their job gets easier. A study¹ found that as little as 20 minutes of moderate exercise stimulates the immune system and triggers an anti-inflammatory immune response in the cells. The natural killer (NK) cells, T4 and T8 lymphocytes and phagocytes in the blood are involved in this process. These cells "come to life" when some kind of pathogen enters the system. Phagocytes or macrophages are also part of the immune system and are capable of eating up pathogens.

It's important to point out that it's not just about weight training: moderate exercise can also be a 20-30-minute walk, bike riding with your family or (of course) weight training or calisthenics. A study revealed that due to regular physical activity the level of new white blood cells in the blood of a 65-year old person (this is the age limit when the coronavirus disease might even be lethal) reached a level that is normal for a 30-year old.

If you are in the vulnerable age group and haven't exercised so far, now it's high time to start. It's true what they say: it's never too late to begin.

When less is more

Exercise can also be harmful to your immune system. A 2019² study revealed that marathon runners were more prone to diseases during hardcore periods in their training cycles, and during race seasons. Yes, hardcore exercise is stressful for your system. Moreover, it can also exacerbate the symptoms of viral infections of the upper respiratory tract and increase the risk of catching infections³.

If you torment yourself with the weights for 2 hours each time, or run a half-marathon every day, that will lead to overtraining and an overproduction of cortisol (stress hormone). The result will be a worn-out immune system, body and soul.

We know that exercise is good for the cardiovascular system. We know that it makes the muscles stronger. On the other hand, that's not so self-evident either. Because, if you work out incorrectly or do joint-killer exercises like behind-the-neck shoulder presses, you might even tear your muscles, instead of strengthening them.

We have highlighted several times that ideally, the duration of a workout session should not considerably exceed 1 hour, and this applies in these circumstances (home training) as well. Also be aware that now it may be difficult to keep 30-60-second rest breaks between sets and exercises, so be more conscious about that, too. Because keeping rest breaks too short can also be harmful.

However, overexertion is less likely to occur during home training, especially if you trained in a gym before. And this is good news. If you are an experienced athlete, your immune system must be as strong as an ox, and it will remain so, if you keep on working out at home. As you could see, as little as 20 minutes of daily physical exercise is enough to keep your immune system in shape. This way you don't need to be afraid of cortisol. But even when everything gets back to normal, you should in no way train like Béla Kathi used to, if your life immune system matters.

If you are new to weights, don't plunge into it too radically, but increase the load gradually. Also, it's a good idea to have a shake or a hearty meal with protein and carbs after workout. For newbies, a minimum of 3 x 30 minutes of exercise is recommended per week.

You can find loads of articles on home training on the Builder site: feel free to dive in, if you haven't done so far. Bottom line: don't let yourself go during the lockdown. It's up to you, whether you make training one of the best friends or worst enemies of your immune system...

Bibliography:

^{1: Exercise ... It does a body good: 20 minutes can act as anti-inflammatory}

^{2: The compelling link between physical activity and the body's defense system}

^{3: PHYSIOLOGY AND NUTRITION, Recommendations to maintain immune health in athletes}