Carbs, exercise and immunity.

News Written by John Mulvey

I heard exercise can suppress the immune system? Should I continue to exercise and train during the COVID-19 pandemic? 

Yes, you should definitely continue to exercise! There are two reasons to do so:

1. The epidemiological data we have on COVID-19 indicate that the risk of dying if you are infected is approximately equal to your risk of dying from any other cause within the next year [1]. Or in other words, the healthier you are the less likely you are to die due to COVID-19. Exercise is known, almost without exception, to be beneficial to health: if you are living in the developed world, all the major causes of death have been linked to physical inactivity [2]. This also fits with the emerging data on detrimental comorbidities for COVID-19 [3].

We’re now over a year into the pandemic, which has made it clear that what many people initially thought back in March last year would be a few weeks hunkered down will involve long term changes to our lives. You should therefore consider both the implications of your training on your risk of COVID-19, but also for all other diseases related to physical inactivity.

There is therefore every reason to exercise! We’ve covered before how carbohydrate consumption during exercise is a no-brainer solution to increase your exercise capability and thus the beneficial effects upon your health. (The Body’s High-Octane Fuel - Carbohydrate

2. It is actually somewhat controversial that exercise suppresses the immune system. This science is really hard to do well, and there are a number of confounding factors that are overlooked in much of the current research [4]. There is at least some evidence that small amounts of exercise may stimulate the immune system, and that large amounts may be detrimental.

I’m going to take the assumption that many of you will (like me) continue to train hard regardless, and so the question then becomes if there’s anything we can do to mitigate the potential immunosuppression? As luck would have it, carbohydrate intake during exercise has been found to reverse the suppressive effects [5]. In particular, a part of your immune system called the T-cell response had higher activity after drinking carbohydrates during exercise compared with placebo [6]. This is really important since the T-cell mediated immunity is thought to be particularly important in protection against the virus that causes COVID-19.

In short, fill your bottles with SUSTAIN (as covered before, scientifically formulated to maximise carbohydrate absorption), and refuel well afterwards with either a full meal or RESET if you’re on the move and it’s going to be a few hours before you eat otherwise.


John Mulvey, PhD

Disclaimer: This article does not constitute medical advice; any changes in your lifestyle should be taken following discussion with your primary care physician.







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