The immunological case for staying active.

We all know that exercise is good for us. And right now during this current period of social isolation, exercising is especially important – in fact, a recent study highlighted how physical activities can afford us access to more immunological benefits. So even if your gym is temporarily closed or your usual fitness regimen has been derailed by changes in your daily routine, it’s critical to find alternate ways to keep moving.

A recent article in Science Direct – Brain, Behavior and Immunity identified several key points that make the case for staying active during the current COVID health events:

1.  Regular physical activity offers numerous health effects, but perhaps more importantly to note in light of this pandemic, is how exercise can enhance immune defense and mitigate the deleterious effects of stress on immunity.

2. Epidemiological data also indicate that physically active people are less likely to report symptoms of upper respiratory illness. There is evidence too that exercise can protect the host from many types of viral infections such as influenza, rhinovirus (just one cause of the common cold) and the reactivation of latent herpesviruses such as Epstein-Barr (EBV), varicella-zoster (VZV) and herpes-simplex-virus-1 (HSV-1). While there is not as yet specific data regarding exercise and coronaviruses, the researchers noted that having elevated levels of cardiorespiratory fitness and exercising at moderate to vigorous intensity can improve immune markers in several conditions including cardiovascular disease, diabetes and cognitive impairment.

3.  Periods of isolation and confinement elevate glucocorticoids (e.g. cortisol) that can inhibit many critical functions of our immune system. Cortisol is often referred to as the “stress hormone” and when elevated for long periods can cause, among other health issues, problems with memory and thinking as well as disrupt our normal and necessary sleep cycles. Imagine being in a “fight or flight” state all the time – that’s just not ideal for our brains or bodies.

4.  Physically active individuals also exert better control over their latent viral infections, even during periods of isolation and confinement. In other words, even if you do get sick your system is in a better position to fight it and possibly inhibit a reactivation of the infection.

5. Mobilization of immune cells needed to fight infection also occurs during exercise.

6.  Exercise releases various cytokines from the skeletal muscle (e.g. myokines) that can help maintain immune competence, your body’s ability to produce a normal immune response following exposure to an antigen.

The regular Physical Activity Guidelines for Americans recommend adults aim for 150 to 300 minutes of moderate to vigorous intensity cardiorespiratory physical activity per week (as physically able and with the ) and two sessions per week of muscle strength training.

Older individuals should also include balance training and aerobic exercise as well as muscle-strengthening activities – and all adults with or without any health conditions should consult their physician prior to starting any program or if you experience any breathing or other difficulties. Remember too that you can always break up any activity into smaller chunks throughout the day. So if walking 15 minutes, twice a day is more manageable than one 30-minute stretch, that’s great too!

While it may seem difficult to achieve these goals in the absence of a traditional gym setting, if that was part of your routine, there are many ways to exercise without investing in expensive or special equipment:

▪ Walking
▪ Jogging
▪ Climbing stairs
▪ Housework that requires a bit more strenuous effort (e.g. vacuuming, cleaning out the garage)
▪ Yard work and similar activities.
▪ Look around the house for items that can be used as weights (a gallon of milk or water or 1 lb. cans of vegetables would work!) or check out your streaming services for online yoga or Pilates instruction.

A report that gathered data from over 140 studies conducted by the University of East Anglia, U.K. also found that “living close to nature and spending time outside has significant and wide-ranging health benefits.” These benefits ranged from a reduced risk of high blood pressure to lowered stress and anxiety levels. Study results representing millions of participants in 20 countries, including the U.S., indicated that access to green space (whether open, undeveloped land or urban parks or street greenery) “significantly reduces people's levels of salivary cortisol -- a physiological marker of stress.” All great reasons to head outdoors for your next exercise session!

Just as important is to avoid sitting for prolonged (more than 60 minutes) periods – set a timer if you need a reminder to get up and move whether you are working at home or helping children with virtual classes. In fact, staying active can be easier to stick to when you make it a family affair.

While exercise can’t prevent us from contracting COVID 19, it’s definitely something that we should include in our personal tool chest of healthy defense habits that could provide a much-needed boost to the immune system throughout everyone’s lifetime.

In health,
Dr. Suzanne Gazda

Additional references:
https://www.sciencedaily.com/releases/2020/03/200331162314.htm